Generelle Ausnahmenanzeige

ChatController/ChatController.csproj

@@ -78,6 +78,9 @@
     <Compile Include="Core\OwnChatCache.cs" />
     <Compile Include="Core\OwnChatRichTextBox.cs" />
     <Compile Include="Data\LookupResult.cs" />
+    <Compile Include="ExceptionViewControl.xaml.cs">
+      <DependentUpon>ExceptionViewControl.xaml</DependentUpon>
+    </Compile>
     <Compile Include="Extensions\IDictionaryTExtensions.cs" />
     <Compile Include="Extensions\IListTExtensions.cs" />
     <Compile Include="HauptKlassen\Chat.cs" />
@@ -126,6 +129,10 @@
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
     </Page>
+    <Page Include="ExceptionViewControl.xaml">
+      <SubType>Designer</SubType>
+      <Generator>MSBuild:Compile</Generator>
+    </Page>
     <Page Include="LoginControl.xaml">
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>

ChatController/ChatEmojiiControl.xaml.cs

@@ -1,5 +1,4 @@
-using System;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Threading;
 using System.Windows;
 using System.Windows.Controls;
@@ -81,23 +80,16 @@ namespace ChatController
 
         public void PassEmojiToChatMainControl(string emojiCode)
         {
-            try
-            {
-                Dispatcher.Invoke(
-                    DispatcherPriority.Normal,
-                    (ThreadStart) delegate
-                    {
-                        _ChatMainControl.Chatbox.Focus();
+            Dispatcher.Invoke(
+                DispatcherPriority.Normal,
+                (ThreadStart) delegate
+                {
+                    _ChatMainControl.Chatbox.Focus();
 
-                        var selectionStart = _ChatMainControl.Chatbox.SelectionStart;
-                        _ChatMainControl.Chatbox.Text = _ChatMainControl.Chatbox.Text.Insert(selectionStart, emojiCode);
-                        _ChatMainControl.Chatbox.SelectionStart = selectionStart + emojiCode.Length;
-                    });
-            }
-            catch (Exception e)
-            {
-                MessageBox.Show(e.Message);
-            }
+                    var selectionStart = _ChatMainControl.Chatbox.SelectionStart;
+                    _ChatMainControl.Chatbox.Text = _ChatMainControl.Chatbox.Text.Insert(selectionStart, emojiCode);
+                    _ChatMainControl.Chatbox.SelectionStart = selectionStart + emojiCode.Length;
+                });
         }
     }
 }

ChatController/ChatKlassen/Contact.cs

@@ -67,11 +67,13 @@ namespace ChatController.ChatKlassen
             get => _Image;
             set
             {
-                if(!Equals(_Image, value))
+                if(Equals(_Image, value))
                 {
-                    _Image = value;
-                    OnPropertyChanged(nameof(Image));
+                    return;
                 }
+
+                _Image = value;
+                OnPropertyChanged(nameof(Image));
             }
         }
 

ChatController/ChatMainControl.xaml

@@ -11,7 +11,7 @@
              mc:Ignorable="d"
              d:DesignHeight="300" d:DesignWidth="600" 
              Loaded="ChatMainControl_OnLoaded"
-             SnapsToDevicePixels="True" d:DataContext="{d:DesignData Type=ChatMainControl}">
+             SnapsToDevicePixels="True" d:DataContext="{d:DesignData Type=chatController:ChatMainControl}">
     <UserControl.Resources>
         <converter:BoolToVisibilityConverter x:Key="BoolToVisibilityConverter" />
         <converter:StringEmptyToVisibilityConverter x:Key="StringEmptyToVisibilityConverter" />

ChatController/ChatMainControl.xaml.cs

@@ -40,7 +40,6 @@ using Timer        = System.Windows.Forms.Timer;
 
 namespace ChatController
 {
-    // Test
     public partial class ChatMainControl : INotifyPropertyChanged
     {
         private readonly Dictionary<long, List<NotifyIcon>> _Group2NotifyIcons = new Dictionary<long, List<NotifyIcon>>();
@@ -55,14 +54,16 @@ namespace ChatController
 
             set
             {
-                if(!Equals(_ThreadExceptionMessage, value))
+                if(Equals(_ThreadExceptionMessage, value))
                 {
-                    _ThreadExceptionMessage = value;
-                    OnPropertyChanged(nameof(ThreadExceptionMessage));
-                    OnPropertyChanged(nameof(CurrentContactInformationString));
-                    OnPropertyChanged(nameof(CurrencContactInfoForeground));
-                    OnPropertyChanged(nameof(ThreadExceptionImageSource));
+                    return;
                 }
+
+                _ThreadExceptionMessage = value;
+                OnPropertyChanged(nameof(ThreadExceptionMessage));
+                OnPropertyChanged(nameof(CurrentContactInformationString));
+                OnPropertyChanged(nameof(CurrencContactInfoForeground));
+                OnPropertyChanged(nameof(ThreadExceptionImageSource));
             }
         }
 
@@ -84,11 +85,13 @@ namespace ChatController
             {
                 _ContainingWindow = value;
 
-                if(!(value is null))
+                if(value is null)
                 {
-                    _ContainingWindow.Deactivated += ContainingWindowOnDeactivated;
-                    _ContainingWindow.Activated += ContainingWindowOnActivated;
+                    return;
                 }
+
+                _ContainingWindow.Deactivated += ContainingWindowOnDeactivated;
+                _ContainingWindow.Activated += ContainingWindowOnActivated;
             }
         }
 
@@ -115,17 +118,19 @@ namespace ChatController
 
             set
             {
-                if(!Equals(_CurrentContact, value))
+                if(Equals(_CurrentContact, value))
                 {
-                    _CurrentContact = value;
-                    
-                    OnPropertyChanged(nameof(CurrentContact));
-                    OnPropertyChanged(nameof(ChatMessageInputGridVisibility));
-                    OnPropertyChanged(nameof(Chat));
-                    OnPropertyChanged(nameof(CurrentContactInformationString));
-                    OnPropertyChanged(nameof(CurrencContactInfoForeground));
-                    OnPropertyChanged(nameof(ThreadExceptionImageSource));
+                    return;
                 }
+
+                _CurrentContact = value;
+                    
+                OnPropertyChanged(nameof(CurrentContact));
+                OnPropertyChanged(nameof(ChatMessageInputGridVisibility));
+                OnPropertyChanged(nameof(Chat));
+                OnPropertyChanged(nameof(CurrentContactInformationString));
+                OnPropertyChanged(nameof(CurrencContactInfoForeground));
+                OnPropertyChanged(nameof(ThreadExceptionImageSource));
             }
         }
 
@@ -199,25 +204,17 @@ namespace ChatController
 
                     foreach(var file in files)
                     {
-                        if(File.Exists(file))
+                        if(!File.Exists(file))
                         {
-                            try
-                            {
-                                File.Delete(file);
-                            }
-                            catch(IOException)
-                            {
-                            
-                            }
+                            continue;
                         }
+
+                        File.Delete(file);
                     }
                 }
                 finally
                 {
-                    this.Dispatch(() =>
-                    {
-                        EndWaiting();
-                    });
+                    this.Dispatch(EndWaiting);
                 }
             });
 
@@ -263,7 +260,6 @@ namespace ChatController
 
             _ContactList = new ObservableSortCollection<ContactDependencyObject>();
 
-            // ToDo: Hier tritt eine NullPointer-Exception auf!
             foreach(var contact in Chat.AddContacts())
             {
                 ContactList.Add(new ContactDependencyObject(contact));
@@ -299,7 +295,7 @@ namespace ChatController
 
             var contact = _ContactList.FirstOrDefault(a => a.Contact.GroupId == pGroupId);
 
-            if (!(contact is null))
+            if(!(contact is null))
             {
                 notificationIcon = Utils.ImageSourceToIcon(contact.Contact.Image);
             }
@@ -331,7 +327,7 @@ namespace ChatController
             
             notifyIcon.BalloonTipClosed += (sender, args) =>
             {
-                // TODO: wird beim ausblenden bzw. automatischem Schließen des "Balloons" ausgelöst
+                // Wird beim ausblenden bzw. automatischem Schließen des "Balloons" ausgelöst
                 DisposeAndRemoveNotification((NotifyIcon)sender, pGroupId);
             };
 
@@ -386,94 +382,75 @@ namespace ChatController
 
         private void SelectContact(Contact contact)
         {
-            try
+            if(contact is null)
             {
-                if(contact is null)
+                return;
+            }
+
+            ChatMessageFileWrapper = null;
+
+            ShouldInterruptContactsThread = true;
+
+            StartWaitingImmediately();
+
+            _ScrollPrueferAktivieren = false;
+
+            if(contact.HasUnreadMessages)
+            {
+                contact.HasUnreadMessages = false;
+
+                Clientlist.Items.Refresh();
+                OnPropertyChanged(nameof(ContactList));
+            }
+
+            var currentContact = contact;
+            contact.IsNewMessage = false;
+
+            var shouldChangeIcon = _ContactList.Any(contactDependencyObject => contactDependencyObject.Contact.IsNewMessage);
+            if(shouldChangeIcon)
+            {
+                ContainingWindow.Icon = Utils.ConvertIconToImageSource(Resource.ownchat_favicon);
+            }
+
+            CurrentContact = currentContact;
+
+            OnPropertyChanged(nameof(IsSendButtonEnabled));
+
+            foreach(ContactDependencyObject item in Clientlist.Items)
+            {
+                if(item.Contact.Equals(contact))
                 {
-                    return;
+                    Clientlist.SelectedItem = item;
                 }
+            }
 
-                ChatMessageFileWrapper = null;
+            _ChatMessages.Clear();
+            OnPropertyChanged(nameof(_ChatMessages));
 
-                ShouldInterruptContactsThread = true;
-
-                StartWaitingImmediately();
-
-                _ScrollPrueferAktivieren = false;
-
-                if(contact.HasUnreadMessages)
+            Chat.LoadChatMessagesForContactAsync(currentContact, GetFirstMessage(), chatMessages =>
+            {
+                this.Dispatch(() =>
                 {
-                    contact.HasUnreadMessages = false;
+                    _ChatMessages.Clear();
+                    _ChatMessages.AddRangeIfElementsNotIn(chatMessages);
+                    OnPropertyChanged(nameof(_ChatMessages));
 
-                    Clientlist.Items.Refresh();
-                    OnPropertyChanged(nameof(ContactList));
-                }
+                    WpfUtils.ScrollToBottomOfListBox(ChatListBox);
 
-                var currentContact = contact;
-                contact.IsNewMessage = false;
+                    ChatListBox.ContextMenu = Chat.ErstelleKontextMenue();
+                    SetContextHandler();
+                    _ScrollPrueferAktivieren = true;
 
-                var shouldChangeIcon = _ContactList.Any(contactDependencyObject => contactDependencyObject.Contact.IsNewMessage);
-                if(shouldChangeIcon)
-                {
-                    ContainingWindow.Icon = Utils.ConvertIconToImageSource(Resource.ownchat_favicon);
-                }
+                    ListenForMessages();
+                    Cursor = Cursors.Arrow;
 
-                CurrentContact = currentContact;
+                    WriteToNewSyncFile();
 
-                OnPropertyChanged(nameof(IsSendButtonEnabled));
+                    ShouldInterruptContactsThread = false;
 
-                foreach(ContactDependencyObject item in Clientlist.Items)
-                {
-                    if(item.Contact.Equals(contact))
-                    {
-                        Clientlist.SelectedItem = item;
-                    }
-                }
-
-                _ChatMessages.Clear();
-                OnPropertyChanged(nameof(_ChatMessages));
-
-                Chat.LoadChatMessagesForContactAsync(currentContact, GetFirstMessage(), chatMessages =>
-                {
-                    this.Dispatch(() =>
-                    {
-                        _ChatMessages.Clear();
-                        _ChatMessages.AddRangeIfElementsNotIn(chatMessages);
-                        OnPropertyChanged(nameof(_ChatMessages));
-
-                        WpfUtils.ScrollToBottomOfListBox(ChatListBox);
-
-                        ChatListBox.ContextMenu = Chat.ErstelleKontextMenue();
-                        SetContextHandler();
-                        _ScrollPrueferAktivieren = true;
-
-                        ListenForMessages();
-                        Cursor = Cursors.Arrow;
-
-                        WriteToNewSyncFile();
-
-                        ShouldInterruptContactsThread = false;
-
-                        EndWaiting();
-                    });
+                    EndWaiting();
                 });
-            }
-            catch(Exception exception)
-            {
-#if DEBUG
-                var desktop = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory);
-
-                using(var fileStream = new FileStream(Path.Combine(desktop, "ownchat_log.txt"), FileMode.OpenOrCreate))
-                {
-                    using(var streamWriter = new StreamWriter(fileStream))
-                    {
-                        streamWriter.WriteLine(exception.ToString());
-                    }
-                }
-#endif
-
-                MessageBox.Show(exception.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-            }
+            });
         }
 
         private void SetContextHandler()
@@ -514,16 +491,18 @@ namespace ChatController
             }
 
             // neu und vor Einfügen setzen und anpassen
-            if(contextItems.Count > 2)
+            if(contextItems.Count <= 2)
             {
-                var copyMenuItem = (MenuItem) contextItems[2];
-                copyMenuItem.Click += CopyOnClick;
+                return;
             }
+
+            var copyMenuItem = (MenuItem) contextItems[2];
+            copyMenuItem.Click += CopyOnClick;
         }
 
         private void SaveAsOnClick(object sender, RoutedEventArgs routedEventArgs)
         {
-            foreach (var items in ChatListBox.SelectedItems)
+            foreach(var items in ChatListBox.SelectedItems)
             {
                 var chatMessage = (ChatMessage) items;
 
@@ -658,42 +637,44 @@ namespace ChatController
             {
                 var pathToOriginalImage = Chat.OpenFile();
 
-                if(File.Exists(pathToOriginalImage)) 
+                if(!File.Exists(pathToOriginalImage))
                 {
-                    StartWaitingImmediately("Skaliere Bild ...");
-
-                    var scalingTask = new Task(() =>
-                    {
-                        try
-                        {
-                            var pathToScaledImage = FileUtils.ScaleImage(pathToOriginalImage, Path.GetExtension(pathToOriginalImage.ToUpperInvariant()), Chat.ChatDaten.MaxUploadSize);
-
-                            var isFileSizeTooLarge = FileUtils.CheckFileSize(pathToScaledImage, Chat.ChatDaten.MaxUploadSize);
-
-                            if(isFileSizeTooLarge)
-                            {
-                                this.Dispatch(() =>
-                                {
-                                    EndWaiting();
-                                    MessageBox.Show($"Die ausgewählte Datei ist zu groß. Die maximale Größe beträgt {Chat.ChatDaten.MaxUploadSize / 1000 / 1000} MB", "Senden nicht möglich", MessageBoxButton.OK, MessageBoxImage.Warning);
-                                });
-
-                                return;
-                            }
-
-                            if(File.Exists(pathToScaledImage))
-                            {
-                                ChatMessageFileWrapper = new ChatMessageFileWrapper(pathToOriginalImage, pathToScaledImage, $"{Chat.ChatDaten.ServerUrl}/document.png");
-                            }
-                        }
-                        finally
-                        {
-                            this.Dispatch(EndWaiting);
-                        }
-                    });
-
-                    scalingTask.Start();
+                    return;
                 }
+
+                StartWaitingImmediately("Skaliere Bild ...");
+
+                var scalingTask = new Task(() =>
+                {
+                    try
+                    {
+                        var pathToScaledImage = FileUtils.ScaleImage(pathToOriginalImage, Path.GetExtension(pathToOriginalImage.ToUpperInvariant()), Chat.ChatDaten.MaxUploadSize);
+
+                        var isFileSizeTooLarge = FileUtils.CheckFileSize(pathToScaledImage, Chat.ChatDaten.MaxUploadSize);
+
+                        if(isFileSizeTooLarge)
+                        {
+                            this.Dispatch(() =>
+                            {
+                                EndWaiting();
+                                MessageBox.Show($"Die ausgewählte Datei ist zu groß. Die maximale Größe beträgt {Chat.ChatDaten.MaxUploadSize / 1000 / 1000} MB", "Senden nicht möglich", MessageBoxButton.OK, MessageBoxImage.Warning);
+                            });
+
+                            return;
+                        }
+
+                        if(File.Exists(pathToScaledImage))
+                        {
+                            ChatMessageFileWrapper = new ChatMessageFileWrapper(pathToOriginalImage, pathToScaledImage, $"{Chat.ChatDaten.ServerUrl}/document.png");
+                        }
+                    }
+                    finally
+                    {
+                        this.Dispatch(EndWaiting);
+                    }
+                });
+
+                scalingTask.Start();
             }
             else
             {
@@ -772,41 +753,36 @@ namespace ChatController
 
         private void Chatbox_OnGotFocus(object sender, RoutedEventArgs e)
         {
-            if (Chatbox.Text.Equals("Nachricht schreiben"))
+            if(!Chatbox.Text.Equals("Nachricht schreiben"))
             {
-                Chatbox.Text = string.Empty;
-                Chatbox.Foreground = new SolidColorBrush(Colors.Black);
+                return;
             }
+
+            Chatbox.Text = string.Empty;
+            Chatbox.Foreground = new SolidColorBrush(Colors.Black);
         }
 
         private void Chatbox_OnKeyDownHandler(object sender, KeyEventArgs e)
         {
-            try
-            {
-                //if (e.Key == Key.Return)
-                //{
-                //    if(CurrentContact != null && !string.IsNullOrEmpty(Chatbox.Text))
-                //    {
-                //        Chat.AddNewMessage(Chatbox.Text, CurrentContact.GroupId);
+            //if (e.Key == Key.Return)
+            //{
+            //    if(CurrentContact != null && !string.IsNullOrEmpty(Chatbox.Text))
+            //    {
+            //        Chat.AddNewMessage(Chatbox.Text, CurrentContact.GroupId);
 
-                //        OnPropertyChanged(nameof(CurrentChatMessages));
+            //        OnPropertyChanged(nameof(CurrentChatMessages));
 
-                //        ChatListBox.Items.MoveCurrentToLast();
-                //        ChatListBox.ScrollIntoView(ChatListBox.Items.CurrentItem);
+            //        ChatListBox.Items.MoveCurrentToLast();
+            //        ChatListBox.ScrollIntoView(ChatListBox.Items.CurrentItem);
 
-                //        Chat.SendMessage(Chatbox.Text, CurrentContact.GroupId);
+            //        Chat.SendMessage(Chatbox.Text, CurrentContact.GroupId);
 
-                //        Chatbox.Text = string.Empty;
-                //    }
-                //}
+            //        Chatbox.Text = string.Empty;
+            //    }
+            //}
 
-                OnPropertyChanged(nameof(IsBroadcastButtonEnabled));
-                OnPropertyChanged(nameof(IsSendButtonEnabled));
-            }
-            catch (Exception ed)
-            {
-                MessageBox.Show("Beim Senden einer Nachricht ist ein Fehler aufgetreten. " + ed.Message + "\n" + ed.StackTrace, "Fehler", MessageBoxButton.OK);
-            }
+            OnPropertyChanged(nameof(IsBroadcastButtonEnabled));
+            OnPropertyChanged(nameof(IsSendButtonEnabled));
         }
 
         private void Chatbox_OnKeyUpHandler(object sender, KeyEventArgs e)
@@ -827,9 +803,9 @@ namespace ChatController
         private void Chat_OnScrollChanged(object sender, ScrollChangedEventArgs e)
         {
             var scrollBarList = Utils.GetVisualChildCollection<ScrollBar>(ChatListBox);
-            foreach (var scrollBar in scrollBarList)
+            foreach(var scrollBar in scrollBarList)
             {
-                if (scrollBar.Orientation == Orientation.Horizontal)
+                if(scrollBar.Orientation == Orientation.Horizontal)
                 {
                     _ScrollPrueferAktivieren = true;
                 }
@@ -842,38 +818,44 @@ namespace ChatController
 
         private void VerticalScrollbarChanged(object sender, RoutedPropertyChangedEventArgs<double> routedPropertyChangedEventArgs)
         {
-            if (_ScrollPrueferAktivieren)
+            if(!_ScrollPrueferAktivieren)
             {
-                var scrollBar = (ScrollBar) sender;
+                return;
+            }
 
-                if(!(scrollBar.Value > 0))
+            var scrollBar = (ScrollBar) sender;
+
+            if(scrollBar.Value > 0)
+            {
+                return;
+            }
+
+            StartWaitingImmediately();
+
+            _ScrollPrueferAktivieren = false;
+
+            ChatMessages.MoveCurrentToFirst();
+
+            var currentChatMessage = ChatMessages.CurrentItem;
+
+            if(Clientlist.SelectedItem is null)
+            {
+                return;
+            }
+
+            var selectedContact = ((ContactDependencyObject) Clientlist.SelectedItem).Contact;
+
+            Chat.LoadMoreMessagesAsync(selectedContact, GetFirstMessage(), chatMessages =>
+            {
+                this.Dispatch(() =>
                 {
-                    StartWaitingImmediately();
+                    EndWaiting();
 
-                    _ScrollPrueferAktivieren = false;
+                    _ChatMessages.AddRangeIfElementsNotIn(chatMessages);
 
-                    ChatMessages.MoveCurrentToFirst();
-
-                    var currentChatMessage = ChatMessages.CurrentItem;
-
-                    if(!(Clientlist.SelectedItem is null))
-                    {
-                        var selectedContact = ((ContactDependencyObject) Clientlist.SelectedItem).Contact;
-
-                        Chat.LoadMoreMessagesAsync(selectedContact, GetFirstMessage(), chatMessages =>
-                        {
-                            this.Dispatch(() =>
-                            {
-                                EndWaiting();
-
-                                _ChatMessages.AddRangeIfElementsNotIn(chatMessages);
-
-                                ChatListBox.ScrollIntoView(currentChatMessage);
-                            });
-                        });
-                    }
-                }
-            }         
+                    ChatListBox.ScrollIntoView(currentChatMessage);
+                });
+            });
         }
 
         private void ListenForMessages()
@@ -906,74 +888,70 @@ namespace ChatController
 
                         this.Dispatch(() =>
                         {
-                            try
+                            foreach (var contactDependencyObject in _ContactList)
                             {
-                                foreach (var contactDependencyObject in _ContactList)
+                                foreach (var newContact in updatedContacts)
                                 {
-                                    foreach (var newContact in updatedContacts)
+                                    if(contactDependencyObject.Contact.GroupId != newContact.GroupId)
                                     {
-                                        if (contactDependencyObject.Contact.GroupId == newContact.GroupId)
-                                        {
-                                            // ReceivedMessage kann null sein!
-                                            if (!(contactDependencyObject.Contact.ReceivedMessage is null) && !contactDependencyObject.Contact.ReceivedMessage.Id.Equals(newContact.ReceivedMessage?.Id))
-                                            {
-                                                contactDependencyObject.Contact.ReceivedMessage = newContact.ReceivedMessage;
-                                                contactDependencyObject.Contact.TimeStamp = newContact.TimeStamp;
-
-                                                Contact selectedContact = null;
-
-                                                if(Clientlist.SelectedItem is ContactDependencyObject selectedContactDependencyObject)
-                                                {
-                                                    selectedContact = selectedContactDependencyObject.Contact;
-                                                }
-
-                                                // Angemeldeter Benutzer
-                                                var userOid = Chat.ChatDaten.LoggedInUser.Response.User.Oid;
-
-                                                var senderId = contactDependencyObject.Contact.ReceivedMessage?.UserId;
-                                                var receiverId = userOid;
-                                                var receiverGroupId = newContact.GroupId;
-                                                var selectedGroupId = selectedContact?.GroupId;
-
-                                                if (senderId != receiverId && (_IsInBackground || receiverGroupId != selectedGroupId))
-                                                {
-                                                    if (!(ContainingWindow is null))
-                                                    {
-                                                        ContainingWindow.Icon = Utils.ConvertIconToImageSource(Resource.oC_favico_NewMessage);
-                                                    }
-
-                                                    ShowNotification(newContact.Name, newContact.ReceivedMessage, newContact.GroupId);
-                                                }
-
-                                                // Wenn der momentan ausgewählte Kontakt der aktuelle Kontakt in der Schleife ist, werden die Nachrichten nicht als ungelesen angezeigt, sonst schon.
-                                                if (!(CurrentContact is null) && newContact.GroupId == CurrentContact.GroupId)
-                                                {
-                                                    contactDependencyObject.Contact.HasUnreadMessages = false;
-                                                }
-                                                else
-                                                {
-                                                    contactDependencyObject.Contact.HasUnreadMessages = true;
-                                                    contactDependencyObject.Contact.IsNewMessage = true;
-                                                }
-                                            }
-                                        }
+                                        continue;
                                     }
 
-                                    if (!updatedContacts.Contains(contactDependencyObject.Contact))
+                                    // ReceivedMessage kann null sein!
+                                    if(contactDependencyObject.Contact.ReceivedMessage is null || contactDependencyObject.Contact.ReceivedMessage.Id.Equals(newContact.ReceivedMessage?.Id))
                                     {
-                                        _ContactList.ToList().Remove(contactDependencyObject);
+                                        continue;
+                                    }
+
+                                    contactDependencyObject.Contact.ReceivedMessage = newContact.ReceivedMessage;
+                                    contactDependencyObject.Contact.TimeStamp = newContact.TimeStamp;
+
+                                    Contact selectedContact = null;
+
+                                    if(Clientlist.SelectedItem is ContactDependencyObject selectedContactDependencyObject)
+                                    {
+                                        selectedContact = selectedContactDependencyObject.Contact;
+                                    }
+
+                                    // Angemeldeter Benutzer
+                                    var userOid = Chat.ChatDaten.LoggedInUser.Response.User.Oid;
+
+                                    var senderId = contactDependencyObject.Contact.ReceivedMessage?.UserId;
+                                    var receiverId = userOid;
+                                    var receiverGroupId = newContact.GroupId;
+                                    var selectedGroupId = selectedContact?.GroupId;
+
+                                    if(senderId != receiverId && (_IsInBackground || receiverGroupId != selectedGroupId))
+                                    {
+                                        if(!(ContainingWindow is null))
+                                        {
+                                            ContainingWindow.Icon = Utils.ConvertIconToImageSource(Resource.oC_favico_NewMessage);
+                                        }
+
+                                        ShowNotification(newContact.Name, newContact.ReceivedMessage, newContact.GroupId);
+                                    }
+
+                                    // Wenn der momentan ausgewählte Kontakt der aktuelle Kontakt in der Schleife ist, werden die Nachrichten nicht als ungelesen angezeigt, sonst schon.
+                                    if(!(CurrentContact is null) && newContact.GroupId == CurrentContact.GroupId)
+                                    {
+                                        contactDependencyObject.Contact.HasUnreadMessages = false;
+                                    }
+                                    else
+                                    {
+                                        contactDependencyObject.Contact.HasUnreadMessages = true;
+                                        contactDependencyObject.Contact.IsNewMessage = true;
                                     }
                                 }
 
-                                ContactList.Sort((x, y) => DateTime.Compare(y.Contact.TimeStamp, x.Contact.TimeStamp));
-                                OnPropertyChanged(nameof(ChatMessages));
-                                OnPropertyChanged(nameof(ContactList));
-                            }
-                            catch(Exception exception)
-                            {
-                                Console.WriteLine(exception);
-                                throw;
+                                if(!updatedContacts.Contains(contactDependencyObject.Contact))
+                                {
+                                    _ContactList.ToList().Remove(contactDependencyObject);
+                                }
                             }
+
+                            ContactList.Sort((x, y) => DateTime.Compare(y.Contact.TimeStamp, x.Contact.TimeStamp));
+                            OnPropertyChanged(nameof(ChatMessages));
+                            OnPropertyChanged(nameof(ContactList));
                         });
                     });
                 }
@@ -1025,7 +1003,7 @@ namespace ChatController
 
         private bool UserFilter(object item)
         {
-            if (string.IsNullOrEmpty(Suche.Text))
+            if(string.IsNullOrEmpty(Suche.Text))
             {
                 return true;
             }
@@ -1040,44 +1018,48 @@ namespace ChatController
 
         private void Chat_OnMouseDoubleClick(object sender, MouseButtonEventArgs e)
         {
-            if(ChatListBox.SelectedItems.Count > 0)
+            if(ChatListBox.SelectedItems.Count <= 0)
             {
-                var selectedItem = ChatListBox.SelectedItems[0];
+                return;
+            }
 
-                if(selectedItem is ChatMessage selectedMessage)
+            var selectedItem = ChatListBox.SelectedItems[0];
+
+            if(!(selectedItem is ChatMessage selectedMessage))
+            {
+                return;
+            }
+
+            if(!string.IsNullOrEmpty(selectedMessage.OriginalImage))
+            {
+                var uri = new Uri(selectedMessage.OriginalImage);
+
+                if(uri.IsFile)
                 {
-                    if(!string.IsNullOrEmpty(selectedMessage.OriginalImage))
-                    {
-                        var uri = new Uri(selectedMessage.OriginalImage);
+                    var bitmapImage = new BitmapImage(uri);
+                    bitmapImage.Freeze();
 
-                        if(uri.IsFile)
-                        {
-                            var bitmapImage = new BitmapImage(uri);
-                            bitmapImage.Freeze();
+                    Chat.ShowPictureWindow(bitmapImage, "Test");
 
-                            Chat.ShowPictureWindow(bitmapImage, "Test");
-
-                            return;
-                        }
-
-                        StartWaitingImmediately();
-
-                        Chat.ShowPicture(selectedMessage.OriginalImage, CurrentContact.GroupId, (imageSource, windowTitle) =>
-                        {
-                            this.Dispatch(() =>
-                            {
-                                EndWaiting();
-                                Chat.ShowPictureWindow(imageSource, windowTitle);
-                            });
-                        });
-                    }
-                    else if(!(selectedMessage.FilePath is null))
-                    {
-                        StartWaitingImmediately();
-
-                        LoadDocumentAsync(selectedMessage.FilePath, Path.GetFileName(selectedMessage.FilePath), EndWaiting);
-                    }
+                    return;
                 }
+
+                StartWaitingImmediately();
+
+                Chat.ShowPicture(selectedMessage.OriginalImage, CurrentContact.GroupId, (imageSource, windowTitle) =>
+                {
+                    this.Dispatch(() =>
+                    {
+                        EndWaiting();
+                        Chat.ShowPictureWindow(imageSource, windowTitle);
+                    });
+                });
+            }
+            else if(!(selectedMessage.FilePath is null))
+            {
+                StartWaitingImmediately();
+
+                LoadDocumentAsync(selectedMessage.FilePath, Path.GetFileName(selectedMessage.FilePath), EndWaiting);
             }
         }
 
@@ -1111,11 +1093,10 @@ namespace ChatController
                     callback?.Invoke();
                 }
             }
-            catch(Exception exception)
+            finally
             {
                 EndWaiting();
 
-                MessageBox.Show(exception.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
             }
         }
 
@@ -1128,14 +1109,16 @@ namespace ChatController
 
         public void StartWaitingImmediately(string dialogText = null)
         {
-            if (_WaitLayer is null)
+            if(!(_WaitLayer is null))
             {
-                _WaitLayer = new ChatControlWaitLayer(dialogText);
-                Grid.SetRowSpan(_WaitLayer, 3);
-                RootGrid.Children.Add(_WaitLayer);
-                Panel.SetZIndex(_WaitLayer, int.MaxValue);
-                _WaitLayer.RefreshChatUI();               
+                return;
             }
+
+            _WaitLayer = new ChatControlWaitLayer(dialogText);
+            Grid.SetRowSpan(_WaitLayer, 3);
+            RootGrid.Children.Add(_WaitLayer);
+            Panel.SetZIndex(_WaitLayer, int.MaxValue);
+            _WaitLayer.RefreshChatUI();
         }
 
         public void EndWaiting()
@@ -1144,11 +1127,13 @@ namespace ChatController
                 DispatcherPriority.Background,
                 (Action) delegate
                 {
-                    if(!(_WaitLayer is null))
+                    if(_WaitLayer is null)
                     {
-                        RootGrid.Children.Remove(_WaitLayer);
-                        _WaitLayer = null;
+                        return;
                     }
+
+                    RootGrid.Children.Remove(_WaitLayer);
+                    _WaitLayer = null;
                 });
         }
 
@@ -1197,10 +1182,9 @@ namespace ChatController
                     });
                 });
             }
-            catch (Exception e)
+            finally
             {
                 EndWaiting();
-                MessageBox.Show("Ein Fehler bei der Synchronisation ist aufgetreten.\nFehler:\n" + e.Message, "Fehler", MessageBoxButton.OK);
             }
         }
         
@@ -1209,7 +1193,7 @@ namespace ChatController
         {
             try
             {
-                if (File.Exists(Path.Combine(Utils.GetAndCreateUserAppDataPath(), Resource.SyncFile2Name)))
+                if(File.Exists(Path.Combine(Utils.GetAndCreateUserAppDataPath(), Resource.SyncFile2Name)))
                 {
                     File.SetAttributes(Path.Combine(Utils.GetAndCreateUserAppDataPath(), Resource.SyncFile2Name), FileAttributes.Normal);
                     File.Delete(Path.Combine(Utils.GetAndCreateUserAppDataPath(), Resource.SyncFile2Name));
@@ -1305,16 +1289,18 @@ namespace ChatController
         // Wird im BeWoPlaner benutzt
         public void ResetNumberOfUnreadMessages(Dictionary<long, DateTime> pGroupId2DateTime)
         {
-            if(!(pGroupId2DateTime is null))
+            if(pGroupId2DateTime is null)
             {
-                foreach(var contactDependencyObject in _ContactList)
+                return;
+            }
+
+            foreach(var contactDependencyObject in _ContactList)
+            {
+                foreach(var groupId2DateTime in pGroupId2DateTime)
                 {
-                    foreach(var groupId2DateTime in pGroupId2DateTime)
+                    if(contactDependencyObject.Contact.GroupId == groupId2DateTime.Key)
                     {
-                        if(contactDependencyObject.Contact.GroupId == groupId2DateTime.Key)
-                        {
-                            contactDependencyObject.Contact.HasUnreadMessages = false;
-                        }
+                        contactDependencyObject.Contact.HasUnreadMessages = false;
                     }
                 }
             }
@@ -1351,16 +1337,16 @@ namespace ChatController
 
         public void DeleteTempFiles()  
         {
-            foreach (var file in _CreatedTempFiles)
+            foreach(var file in _CreatedTempFiles)
             {
                 try
                 {
-                    if (File.Exists(file))
+                    if(File.Exists(file))
                     {
                         File.Delete(file);
                     }
                 }
-                catch (Exception)
+                catch(Exception)
                 {
                     //ignore okeee
                 }
@@ -1449,15 +1435,15 @@ namespace ChatController
 
         private CancellationTokenSource _CancellationTokenSource;
 
-        private string _DefaultBroadcastInfoText = "Sie befinden Sich im Stapel-Modus. In diesem Modus können Sie eine Nachricht in einem Schritt an mehrere Empfänger & Gruppen senden. Bitte setzen Sie dazu in der Kontaktliste bei den gewünschten Empfängern & Gruppen ein Häkchen und schreiben Sie Ihre Nachricht wie gewohnt. Wenn Sie auf senden klicken, wird die Nachricht an alle ausgewählten Empfänger & Gruppen gesendet.";
+        private const string DefaultBroadcastInfoText = "Sie befinden Sich im Stapel-Modus. In diesem Modus können Sie eine Nachricht in einem Schritt an mehrere Empfänger & Gruppen senden. Bitte setzen Sie dazu in der Kontaktliste bei den gewünschten Empfängern & Gruppen ein Häkchen und schreiben Sie Ihre Nachricht wie gewohnt. Wenn Sie auf senden klicken, wird die Nachricht an alle ausgewählten Empfänger & Gruppen gesendet.";
 
         private string _BroadcastInfoText;
         public string BroadcastInfoText
         {
-            get => _BroadcastInfoText ?? (_BroadcastInfoText = _DefaultBroadcastInfoText);
+            get => _BroadcastInfoText ?? (_BroadcastInfoText = DefaultBroadcastInfoText);
             set
             {
-                _BroadcastInfoText = $"{_DefaultBroadcastInfoText}{Environment.NewLine}{value}";
+                _BroadcastInfoText = $"{DefaultBroadcastInfoText}{Environment.NewLine}{value}";
                 OnPropertyChanged(BroadcastInfoText);
             }
         }
@@ -1497,7 +1483,7 @@ namespace ChatController
 
             DeselectAllContacts();
 
-            if (Chat.IsInBroadcastMode)
+            if(Chat.IsInBroadcastMode)
             {
                 _CancellationTokenSource = new CancellationTokenSource();
                 _PreviousContact = CurrentContact;
@@ -1598,18 +1584,20 @@ namespace ChatController
 
         private void SelectAllContacts_OnClick(object sender, RoutedEventArgs e)
         {
-            if(sender is CheckBox checkBox)
+            if(!(sender is CheckBox checkBox))
             {
-                var isChecked = checkBox.IsChecked ?? false;
-
-                foreach (var contactDependencyObject in ContactList)
-                {
-                    contactDependencyObject.SetValue(ListItemHelper.IsCheckedProperty, isChecked);
-                }
-
-                OnPropertyChanged(nameof(ContactList));
-                OnPropertyChanged(nameof(IsBroadcastButtonEnabled));
+                return;
             }
+
+            var isChecked = checkBox.IsChecked ?? false;
+
+            foreach(var contactDependencyObject in ContactList)
+            {
+                contactDependencyObject.SetValue(ListItemHelper.IsCheckedProperty, isChecked);
+            }
+
+            OnPropertyChanged(nameof(ContactList));
+            OnPropertyChanged(nameof(IsBroadcastButtonEnabled));
         }
 
         private void SendBroatcastButton_OnClick(object sender, RoutedEventArgs e)
@@ -1626,42 +1614,46 @@ namespace ChatController
 
         private void AddMediaFileToBroadcastMessage_OnClick(object sender, RoutedEventArgs e)
         {
-            if(Chat.IsInBroadcastMode)
+            if(!Chat.IsInBroadcastMode)
             {
-                var originalFilePath = Chat.OpenFile();
-
-                if(File.Exists(originalFilePath))
-                {
-                    StartWaitingImmediately("Skaliere Bild ...");
-
-                    var scalingTask = new Task(() =>
-                    {
-                        try
-                        {
-                            var scaledImagePath = FileUtils.ScaleImage(originalFilePath, Path.GetExtension(originalFilePath.ToUpperInvariant()), Chat.ChatDaten.MaxUploadSize);
-
-                            var isFileSizeTooLarge = FileUtils.CheckFileSize(scaledImagePath, Chat.ChatDaten.MaxUploadSize);
-
-                            if(isFileSizeTooLarge)
-                            {
-                                MessageBox.Show($"Die ausgewählte Datei ist zu groß. Die maximale Größe beträgt {Chat.ChatDaten.MaxUploadSize / 1000 / 1000} MB", "Senden nicht möglich", MessageBoxButton.OK, MessageBoxImage.Warning);
-                                return;
-                            }
-
-                            if(File.Exists(scaledImagePath))
-                            {
-                                BroadcastMessageFileWrapper = new ChatMessageFileWrapper(originalFilePath, scaledImagePath, $"{Chat.ChatDaten.ServerUrl}/document.png");
-                            }
-                        }
-                        finally
-                        {
-                            this.Dispatch(EndWaiting);
-                        }
-                    });
-
-                    scalingTask.Start();
-                }
+                return;
             }
+            
+            var originalFilePath = Chat.OpenFile();
+
+            if(!File.Exists(originalFilePath))
+            {
+                return;
+            }
+
+            StartWaitingImmediately("Skaliere Bild ...");
+
+            var scalingTask = new Task(() =>
+            {
+                try
+                {
+                    var scaledImagePath = FileUtils.ScaleImage(originalFilePath, Path.GetExtension(originalFilePath.ToUpperInvariant()), Chat.ChatDaten.MaxUploadSize);
+
+                    var isFileSizeTooLarge = FileUtils.CheckFileSize(scaledImagePath, Chat.ChatDaten.MaxUploadSize);
+
+                    if(isFileSizeTooLarge)
+                    {
+                        MessageBox.Show($"Die ausgewählte Datei ist zu groß. Die maximale Größe beträgt {Chat.ChatDaten.MaxUploadSize / 1000 / 1000} MB", "Senden nicht möglich", MessageBoxButton.OK, MessageBoxImage.Warning);
+                        return;
+                    }
+
+                    if(File.Exists(scaledImagePath))
+                    {
+                        BroadcastMessageFileWrapper = new ChatMessageFileWrapper(originalFilePath, scaledImagePath, $"{Chat.ChatDaten.ServerUrl}/document.png");
+                    }
+                }
+                finally
+                {
+                    this.Dispatch(EndWaiting);
+                }
+            });
+
+            scalingTask.Start();
         }
 
         private void CloseBroadcastMode()
@@ -1741,7 +1733,7 @@ namespace ChatController
 
         private void DeselectAllContacts()
         {
-            foreach (var contactDependencyObject in ContactList)
+            foreach(var contactDependencyObject in ContactList)
             {
                 contactDependencyObject.SetValue(ListItemHelper.IsCheckedProperty, false);
             }

ChatController/ExceptionViewControl.xaml

@@ -0,0 +1,57 @@
+<UserControl x:Class="ChatController.ExceptionViewControl"
+             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
+             mc:Ignorable="d" 
+             d:DesignHeight="450" d:DesignWidth="800">
+    <UserControl.Resources>
+        <Style x:Key="OrangeButtonStyle" TargetType="{x:Type Button}">
+            <Setter Property="FontSize" Value="14" />
+            <Setter Property="Margin" Value="5" />
+            <Setter Property="Height" Value="40" />
+            <Setter Property="MinWidth" Value="100"></Setter>
+            <Setter Property="BorderBrush" Value="#FF5A00" />
+            <Setter Property="Background" Value="#FF5A00" />
+            <Setter Property="Foreground" Value="White"></Setter>
+            <Setter Property="Template">
+                <Setter.Value>
+                    <ControlTemplate TargetType="{x:Type Button}">
+                        <Border x:Name="Border" Background="#FF5A00" CornerRadius="5" Padding="5,2">
+                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" />
+                        </Border>
+                        <ControlTemplate.Triggers>
+                            <Trigger Property="IsMouseOver" Value="True">
+                                <Setter Property="Background" Value="#FF988F" TargetName="Border" />
+                            </Trigger>
+                            <Trigger Property="IsPressed" Value="True">
+                                <Setter Property="Background" Value="#FF7654" TargetName="Border" />
+                            </Trigger>
+                            <Trigger Property="IsEnabled" Value="False">
+                                <Setter Property="Background" Value="LightGray" TargetName="Border" />
+                            </Trigger>
+                        </ControlTemplate.Triggers>
+                    </ControlTemplate>
+                </Setter.Value>
+            </Setter>
+        </Style>
+    </UserControl.Resources>
+    <Grid>
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="*" />
+            <RowDefinition Height="Auto" />
+        </Grid.RowDefinitions>
+        <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="Auto" />
+            <ColumnDefinition Width="*" />
+            <ColumnDefinition Width="Auto" />
+        </Grid.ColumnDefinitions>
+        <TextBlock Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="3" TextWrapping="Wrap" FontWeight="Bold" Text="Es ist leider ein unbekannter Fehler aufgetreten. Prüfen Sie Ihre Internetverbindung oder versuchen Sie es später erneut. Wir sind stets bemüht, das Programm zu verbessern, daher freuen wir uns auch, wenn Sie die Fehlerdetails unten in einer Mail an support@bewoplaner.de senden." Margin="5, 5, 5, 10" FontSize="14" />
+        <TextBlock Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="3" Margin="5" FontSize="12" TextDecorations="Underline">Fehlerdetails:</TextBlock>
+        <TextBox Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="3" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Margin="5" IsReadOnly="True" Text="{Binding Path=Exception.StackTrace, UpdateSourceTrigger=PropertyChanged, Mode=OneWay}" />
+        <Button Grid.Column="0" Grid.Row="3" Style="{StaticResource OrangeButtonStyle}" HorizontalAlignment="Left" Click="CopyToClipboardButton_OnClick">In die Zwischenablage kopieren</Button>
+        <Button Grid.Column="2" Grid.Row="3" Style="{StaticResource OrangeButtonStyle}" HorizontalAlignment="Right" Click="OkButton_OnClick">OK</Button>
+    </Grid>
+</UserControl>

ChatController/ExceptionViewControl.xaml.cs

@@ -0,0 +1,46 @@
+using System;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+using System.Windows;
+
+namespace ChatController
+{
+    public partial class ExceptionViewControl : INotifyPropertyChanged
+    {
+        public event EventHandler OkButtonClicked;
+
+        private Exception _Exception;
+        public Exception Exception
+        {
+            get => _Exception;
+            set
+            {
+                _Exception = value;
+                OnPropertyChanged();
+            }
+        }
+
+        public ExceptionViewControl()
+        {
+            InitializeComponent();
+            DataContext = this;
+        }
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+
+        private void OkButton_OnClick(object sender, RoutedEventArgs args)
+        {
+            OkButtonClicked?.Invoke(this, args);
+        }
+
+        private void CopyToClipboardButton_OnClick(object sender, RoutedEventArgs args)
+        {
+            Clipboard.SetText(Exception.StackTrace);
+        }
+    }
+}

ChatController/HauptKlassen/Chat.cs

@@ -73,32 +73,25 @@ namespace ChatController.HauptKlassen
 
         private static bool PinPublicKey(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslpolicyerrors)
         {
-            try
-            {
-                if(certificate is null || chain is null)
-                {
-                    return false;
-                }
-
-                var chainContainsPk = false;
-
-                foreach(var element in chain.ChainElements)
-                {
-                    var pk = element.Certificate.GetPublicKeyString();
-                    if(pk == PubKeyX3 || pk == PubKeyR3 || pk == PubKeyE1)
-                    {
-                        chainContainsPk = true;
-                    }
-                }
-
-                var subjectAccepted = certificate.Subject.Trim().ToLower().EndsWith(".bewoplaner.de") || certificate.Subject.Trim().ToLower().EndsWith(".ownchat.de");
-
-                return chainContainsPk && subjectAccepted;
-            }
-            catch(Exception)
+            if(certificate is null || chain is null)
             {
                 return false;
             }
+
+            var chainContainsPk = false;
+
+            foreach(var element in chain.ChainElements)
+            {
+                var pk = element.Certificate.GetPublicKeyString();
+                if(pk == PubKeyX3 || pk == PubKeyR3 || pk == PubKeyE1)
+                {
+                    chainContainsPk = true;
+                }
+            }
+
+            var subjectAccepted = certificate.Subject.Trim().ToLower().EndsWith(".bewoplaner.de") || certificate.Subject.Trim().ToLower().EndsWith(".ownchat.de");
+
+            return chainContainsPk && subjectAccepted;
         }
 
         private const string PubKey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
@@ -134,37 +127,30 @@ namespace ChatController.HauptKlassen
 
         private void LoadMessagesFromServerAsync(long groupId, Action callback)
         {
-            try
+            var url = $"{ChatDaten.ServerUrl}{Constants.LoadMessagesForGroupUrl}{groupId}";
+
+            var client = new RestClient(url);
+            var request = new RestRequest();
+
+            request.AddHeader(Constants.Token, ChatDaten.AuthToken);
+            request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
+
+            client.ExecuteAsync(request, response =>
             {
-                var url = $"{ChatDaten.ServerUrl}{Constants.LoadMessagesForGroupUrl}{groupId}";
+                _UserMessages = JsonConvert.DeserializeObject<UserMessages>(response.Content);
 
-                var client = new RestClient(url);
-                var request = new RestRequest();
-
-                request.AddHeader(Constants.Token, ChatDaten.AuthToken);
-                request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
-
-                client.ExecuteAsync(request, response =>
+                if(_UserMessages?.Response?.HasMorePages ?? false)
                 {
-                    _UserMessages = JsonConvert.DeserializeObject<UserMessages>(response.Content);
-                    
-                    if (_UserMessages?.Response?.HasMorePages ?? false)
-                    {
-                        _NextPage = _UserMessages.Response.NextPage;
-                        _HasNextPage = true;
-                    }
-                    else
-                    {
-                        _HasNextPage = false;
-                    }
+                    _NextPage = _UserMessages.Response.NextPage;
+                    _HasNextPage = true;
+                }
+                else
+                {
+                    _HasNextPage = false;
+                }
 
-                    callback?.Invoke();
-                });
-            }
-            catch (Exception exception)
-            {
-                ThreadExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke();
+            });
         }
 
         public void LoadMoreMessagesAsync(Contact contact, ChatMessage previousMessage, Action<List<ChatMessage>> callback)
@@ -177,43 +163,36 @@ namespace ChatController.HauptKlassen
 
         private void LoadMoreMessagesFromServerAsync(long groupId, string page, Action callback)
         {
-            try
+            if(page is null || !page.Contains("="))
             {
-                if(page is null || !page.Contains("="))
+                callback?.Invoke();
+                return;
+            }
+
+            var pageParam = page.Split('=')[1];
+
+            var url = $"{ChatDaten.ServerUrl}/api/chat/messages?groupid={groupId}&page={pageParam}";
+
+            var client = new RestClient(url);
+            var request = new RestRequest();
+
+            request.AddHeader(Constants.Token, ChatDaten.AuthToken);
+            request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
+
+            client.ExecuteAsync(request, response =>
+            {
+                _AdditionalUserMessages = null;
+                _AdditionalUserMessages = JsonConvert.DeserializeObject<UserMessages>(response.Content);
+
+                if(_AdditionalUserMessages?.Response?.HasMorePages ?? false)
                 {
-                    callback?.Invoke();
-                    return;
+                    _NextPage = _AdditionalUserMessages.Response.NextPage;
                 }
 
-                var pageParam = page.Split('=')[1];
+                _HasNextPage = _AdditionalUserMessages?.Response?.HasMorePages ?? false;
 
-                var url = $"{ChatDaten.ServerUrl}/api/chat/messages?groupid={groupId}&page={pageParam}";
-
-                var client = new RestClient(url);
-                var request = new RestRequest();
-
-                request.AddHeader(Constants.Token, ChatDaten.AuthToken);
-                request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
-
-                client.ExecuteAsync(request, response =>
-                {
-                    _AdditionalUserMessages = null;
-                    _AdditionalUserMessages = JsonConvert.DeserializeObject<UserMessages>(response.Content);
-
-                    if (_AdditionalUserMessages?.Response?.HasMorePages ?? false)
-                    {
-                        _NextPage = _AdditionalUserMessages.Response.NextPage;
-                    }
-
-                    _HasNextPage = _AdditionalUserMessages?.Response?.HasMorePages ?? false;
-
-                    callback?.Invoke();
-                });
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke();
+            });
         }
 
         private double _FormerMessagesCount;
@@ -223,7 +202,7 @@ namespace ChatController.HauptKlassen
             var span = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
             var timespan = Convert.ToInt64(span.TotalSeconds);
 
-            if (!(_UserMessages is null) && _UserMessages.Response.Messages.Length > 0)
+            if(!(_UserMessages is null) && _UserMessages.Response.Messages.Length > 0)
             {
                 timespan = _UserMessages.Response.Messages.First().Created_At;
             }
@@ -259,8 +238,8 @@ namespace ChatController.HauptKlassen
             }
             catch(Exception exception)
             {
-                ExceptionCallback?.Invoke(exception);
                 callback?.Invoke(0d);
+                throw exception;
             }
         }
 
@@ -279,184 +258,125 @@ namespace ChatController.HauptKlassen
 
         private void LoadNumberOfNewMessagesFromServerAsync(long groupId, Action<double> callback)
         {
-            try
+            var url = $"{ChatDaten.ServerUrl}{Constants.LoadOwnChatNewsUrl}{groupId}/{LastTimeStamp}";
+
+            var client = new RestClient(url);
+            var request = new RestRequest();
+
+            request.AddHeader(Constants.Token, ChatDaten.AuthToken);
+            request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
+
+            client.ExecuteAsync(request, response =>
             {
-                var url = $"{ChatDaten.ServerUrl}{Constants.LoadOwnChatNewsUrl}{groupId}/{LastTimeStamp}";
+                var messageCounter = JsonConvert.DeserializeObject<MessageCounter>(response.Content);
 
-                var client = new RestClient(url);
-                var request = new RestRequest();
-
-                request.AddHeader(Constants.Token, ChatDaten.AuthToken);
-                request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
-
-                client.ExecuteAsync(request, response =>
-                {
-                    var messageCounter = JsonConvert.DeserializeObject<MessageCounter>(response.Content);
-
-                    callback?.Invoke(messageCounter?.MessageCount ?? 0);
-                });
-            }
-            catch(Exception exception)
-            {
-                ThreadExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke(messageCounter?.MessageCount ?? 0);
+            });
         }
 
         private void LoadGroupsAsync(Action<ChatGruppenDaten> callback)
         {
-            try
+            var url = $"{ChatDaten.ServerUrl}{Constants.GetChatGroupsUrl}";
+
+            var client = new RestClient(url);
+            var request = new RestRequest();
+
+            request.AddHeader(Constants.Token, ChatDaten.AuthToken);
+            request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
+
+            client.ExecuteAsync(request, response =>
             {
-                var url = $"{ChatDaten.ServerUrl}{Constants.GetChatGroupsUrl}";
+                var contacts = JsonConvert.DeserializeObject<ChatGruppenDaten>(response.Content);
 
-                var client = new RestClient(url);
-                var request = new RestRequest();
-
-                request.AddHeader(Constants.Token, ChatDaten.AuthToken);
-                request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
-
-                client.ExecuteAsync(request, response =>
-                {
-                    var contacts = JsonConvert.DeserializeObject<ChatGruppenDaten>(response.Content);
-
-                    callback?.Invoke(contacts);
-                });
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke(contacts);
+            });
         }
 
         public void UpdateContactList(Action<IOrderedEnumerable<Contact>> callback)
         {
-            try
+            LoadGroupsAsync(rawData =>
             {
-                LoadGroupsAsync(rawData =>
-                {
-                    var contacts = GenerateContactsFromServerResponse(rawData.Response.Groups.ToArray(), true);
+                var contacts = GenerateContactsFromServerResponse(rawData.Response.Groups.ToArray(), true);
 
-                    callback?.Invoke(contacts.OrderByDescending(c => c.TimeStamp));
-                });
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke(contacts.OrderByDescending(c => c.TimeStamp));
+            });
         }
 
         public List<ChatMessage> AddNewMessage(string pMessage, long pGroupId, ChatMessage previousMessage)
         {
-            var result = new List<ChatMessage>();
+            var time = DateTime.Now;
 
-            try
-            {
-                var time = DateTime.Now;
+            var chatMessage = new ChatMessage(pGroupId, 0, ChatDaten.LoggedInUser.Response.User.UserName, pMessage, time, true, 0, null, null, null, null, null, ChatMessageType.Message, ChatDaten.LoggedInUser.Response.User.Oid);
 
-                var chatMessage = new ChatMessage(pGroupId, 0, ChatDaten.LoggedInUser.Response.User.UserName, pMessage, time, true, 0, null, null, null, null, null, ChatMessageType.Message, ChatDaten.LoggedInUser.Response.User.Oid);
-
-                result = AddSeparators(new List<ChatMessage> {previousMessage, chatMessage});
-
-                result.Remove(previousMessage);
-
-                return result;
-            }
-            catch (Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+            var result = AddSeparators(new List<ChatMessage> {previousMessage, chatMessage});
 
+            result.Remove(previousMessage);
+         
             return result;
         }
 
         public async Task SendMessage(string message, long groupId)
         {
-            try
+            var endurl = ChatDaten.ServerUrl + Constants.SendMessageUrl;
+
+            using (var multiPartContent = new MultipartFormDataContent())
             {
-                var endurl = ChatDaten.ServerUrl + Constants.SendMessageUrl;
+                multiPartContent.Add(new StringContent(groupId.ToString()), "groupid");
+                multiPartContent.Add(new StringContent(message), "text");
+                
+                var requestUri = new Uri(endurl);
 
-                using (var multiPartContent = new MultipartFormDataContent())
-                {
-                    multiPartContent.Add(new StringContent(groupId.ToString()), "groupid");
-                    multiPartContent.Add(new StringContent(message), "text");
-                    
-                    var requestUri = new Uri(endurl);
+                var httpRequest = new HttpRequestMessage {Method = HttpMethod.Post, RequestUri = requestUri, Content = multiPartContent};
 
-                    var httpRequest = new HttpRequestMessage {Method = HttpMethod.Post, RequestUri = requestUri, Content = multiPartContent};
+                httpRequest.Headers.Add("Token", ChatDaten.AuthToken);
+                httpRequest.Headers.Add("CustomerID", ChatDaten.Kundennummer);
 
-                    httpRequest.Headers.Add("Token", ChatDaten.AuthToken);
-                    httpRequest.Headers.Add("CustomerID", ChatDaten.Kundennummer);
-
-                    var httpClient = new HttpClient();
-                    await httpClient.SendAsync(httpRequest, CancellationToken.None);
-                }
-            }
-            catch (Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
+                var httpClient = new HttpClient();
+                await httpClient.SendAsync(httpRequest, CancellationToken.None);
             }
         }
 
         public string OpenFile()
         {
-            try
+            var openFileDialog = new OpenFileDialog
             {
-                var openFileDialog = new OpenFileDialog
-                {
-                    Filter = Resource.OpenFileDialogFilter_Test
-                };
+                Filter = Resource.OpenFileDialogFilter_Test
+            };
 
-                var result = openFileDialog.ShowDialog();
-                
-                return result == DialogResult.OK ? openFileDialog.FileName : null;
-            }
-            catch (Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-                return null;
-            }
+            var result = openFileDialog.ShowDialog();
+            
+            return result == DialogResult.OK ? openFileDialog.FileName : null;
         }
 
         public List<ChatMessage> AddNewFile(string pathToScaledFile, string originalFilePath, long groupId, ChatMessage previousMessage, string chatBoxText)
         {
             var result = new List<ChatMessage>();
 
-            try
+            if(string.IsNullOrEmpty(pathToScaledFile) || string.IsNullOrEmpty(originalFilePath))
             {
-                if(string.IsNullOrEmpty(pathToScaledFile) || string.IsNullOrEmpty(originalFilePath))
-                {
-                    return result;
-                }
-
-                var messageId = 0;
-                var userName = ChatDaten.LoggedInUser.Response.User.UserName;
-                var sendTime = DateTime.Now;
-                var fileName = Path.GetFileName(pathToScaledFile);
-                var imageFile = GetImageFile(pathToScaledFile, out var fileSize);
-                var isImage = Constants.ImageFileExtensions.Contains(Path.GetExtension(pathToScaledFile).ToUpperInvariant());
-                var messageText = string.IsNullOrWhiteSpace(chatBoxText) ? fileName : chatBoxText;
-                var filePath = isImage ? null : pathToScaledFile;
-                var originalImage = isImage ? pathToScaledFile : null;
-                var imageName = isImage ? fileName : null;
-                var linkToThumbnail = isImage ? null : $"{ChatDaten.ServerUrl}/document.png";
-                var logo = isImage ? imageFile : null;
-                var chatMessageType = isImage ? ChatMessageType.Image : ChatMessageType.Document;
-                var senderId = ChatDaten.LoggedInUser.Response.User.Oid;
-
-                var chatMessage = new ChatMessage(groupId, messageId, userName, messageText, sendTime, true, fileSize, filePath, originalImage, imageName, linkToThumbnail, logo, chatMessageType, senderId);
-
-                result = AddSeparators(new List<ChatMessage> { previousMessage, chatMessage });
-
-                result.Remove(previousMessage);
-
                 return result;
             }
-            catch(Exception exception)
-            {
-                if(!(exception is IOException))
-                {
-                    ExceptionCallback?.Invoke(exception);
-                }
-            }
+
+            var messageId = 0;
+            var userName = ChatDaten.LoggedInUser.Response.User.UserName;
+            var sendTime = DateTime.Now;
+            var fileName = Path.GetFileName(pathToScaledFile);
+            var imageFile = GetImageFile(pathToScaledFile, out var fileSize);
+            var isImage = Constants.ImageFileExtensions.Contains(Path.GetExtension(pathToScaledFile).ToUpperInvariant());
+            var messageText = string.IsNullOrWhiteSpace(chatBoxText) ? fileName : chatBoxText;
+            var filePath = isImage ? null : pathToScaledFile;
+            var originalImage = isImage ? pathToScaledFile : null;
+            var imageName = isImage ? fileName : null;
+            var linkToThumbnail = isImage ? null : $"{ChatDaten.ServerUrl}/document.png";
+            var logo = isImage ? imageFile : null;
+            var chatMessageType = isImage ? ChatMessageType.Image : ChatMessageType.Document;
+            var senderId = ChatDaten.LoggedInUser.Response.User.Oid;
+
+            var chatMessage = new ChatMessage(groupId, messageId, userName, messageText, sendTime, true, fileSize, filePath, originalImage, imageName, linkToThumbnail, logo, chatMessageType, senderId);
+
+            result = AddSeparators(new List<ChatMessage> { previousMessage, chatMessage });
+
+            result.Remove(previousMessage);
 
             return result;
         }
@@ -533,7 +453,7 @@ namespace ChatController.HauptKlassen
 
             var sendtime = DateTime.Now;
 
-            if (Constants.ImageFileExtensions.Contains(Path.GetExtension(fileName).ToUpperInvariant()))
+            if(Constants.ImageFileExtensions.Contains(Path.GetExtension(fileName).ToUpperInvariant()))
             {
                 var bitmapImage = new BitmapImage();
                 var memoryStream = new MemoryStream(file);
@@ -563,14 +483,7 @@ namespace ChatController.HauptKlassen
 
         public async Task SendFileToContact(Contact currentContact, string scaledImagePath, string originalFilePath, string message)
         {
-            try
-            {
-                await SendFile(scaledImagePath, currentContact, originalFilePath, message);
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+            await SendFile(scaledImagePath, currentContact, originalFilePath, message);
         }
 
         private async Task SendFile(string pFile, Contact currentContact, string pOriginalFilePath, string message)
@@ -659,7 +572,7 @@ namespace ChatController.HauptKlassen
 
         public void SaveFileAs(ChatMessage pChatMessage)
         {
-            if (!(pChatMessage.PictureSource is null))
+            if(!(pChatMessage.PictureSource is null))
             {
                 SaveAs(1, Path.GetFileName(pChatMessage.OriginalImage), DownloadMediaFile(pChatMessage.OriginalImage));
             }
@@ -669,63 +582,47 @@ namespace ChatController.HauptKlassen
         {
             byte[] mediaFile = null;
             
-            try
+            using(var webClient = new WebClient())
             {
-                using(var webClient = new WebClient())
-                {
-                    webClient.Credentials = CredentialCache.DefaultCredentials;
-                    webClient.Headers[Constants.Token] = ChatDaten.AuthToken;
-                    webClient.Headers[Constants.CustomerId] = ChatDaten.Kundennummer;
-                    mediaFile = webClient.DownloadData(pFilePath);
-                }
+                webClient.Credentials = CredentialCache.DefaultCredentials;
+                webClient.Headers[Constants.Token] = ChatDaten.AuthToken;
+                webClient.Headers[Constants.CustomerId] = ChatDaten.Kundennummer;
+                mediaFile = webClient.DownloadData(pFilePath);
+            }
 
-                return mediaFile;
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
-            
             return mediaFile;
         }
 
         private void SaveAs(int pFilterType, string pFileName, byte[] pMediaFile)
         {
-            try
+            var saveFileDialog = new SaveFileDialog {FileName = Path.GetFileName(pFileName)};
+
+            switch(pFilterType)
             {
-                var saveFileDialog = new SaveFileDialog {FileName = Path.GetFileName(pFileName)};
-
-                switch(pFilterType)
-                {
-                    case 1:
-                        saveFileDialog.Filter = Resource.SaveFileDialogFilter_Images;
-                        saveFileDialog.Title = Resource.SaveFIleDialogTitle_Images;
-                        saveFileDialog.ShowDialog();
-                        break;
-                    case 2:
-                        saveFileDialog.Filter = Resource.SaveFileDialogFilter_Documents;
-                        saveFileDialog.Title = Resource.SaveFIleDialogTitle_Documents;
-                        saveFileDialog.ShowDialog();
-                        break;
-                    case 3:
-                        saveFileDialog.Filter = Resource.SaveFileDialogFilter_Audio;
-                        saveFileDialog.Title = Resource.SaveFIleDialogTitle_Audio;
-                        saveFileDialog.ShowDialog();
-                        break;
-                }
-
-                if (!string.IsNullOrEmpty(saveFileDialog.FileName))
-                {
-                    var fileStream = (FileStream)saveFileDialog.OpenFile();
-
-                    fileStream.Write(pMediaFile, 0, pMediaFile.Length);
-
-                    fileStream.Close();
-                }
+                case 1:
+                    saveFileDialog.Filter = Resource.SaveFileDialogFilter_Images;
+                    saveFileDialog.Title = Resource.SaveFIleDialogTitle_Images;
+                    saveFileDialog.ShowDialog();
+                    break;
+                case 2:
+                    saveFileDialog.Filter = Resource.SaveFileDialogFilter_Documents;
+                    saveFileDialog.Title = Resource.SaveFIleDialogTitle_Documents;
+                    saveFileDialog.ShowDialog();
+                    break;
+                case 3:
+                    saveFileDialog.Filter = Resource.SaveFileDialogFilter_Audio;
+                    saveFileDialog.Title = Resource.SaveFIleDialogTitle_Audio;
+                    saveFileDialog.ShowDialog();
+                    break;
             }
-            catch (Exception exception)
+
+            if (!string.IsNullOrEmpty(saveFileDialog.FileName))
             {
-                ExceptionCallback?.Invoke(exception);
+                var fileStream = (FileStream)saveFileDialog.OpenFile();
+
+                fileStream.Write(pMediaFile, 0, pMediaFile.Length);
+
+                fileStream.Close();
             }
         }
 
@@ -740,33 +637,26 @@ namespace ChatController.HauptKlassen
             
             if(dataObject.GetDataPresent(DataFormats.FileDrop))
             {
-                try
+                if(dataObject.GetData(DataFormats.FileDrop) is string[] fileList)
                 {
-                    if(dataObject.GetData(DataFormats.FileDrop) is string[] fileList)
+                    var pathToFile = fileList[0];
+
+                    if(File.Exists(pathToFile))
                     {
-                        var pathToFile = fileList[0];
+                        var fileName = Path.GetFileName(pathToFile);
+                        
+                        var mediaFile = File.ReadAllBytes(pathToFile);
 
-                        if(File.Exists(pathToFile))
-                        {
-                            var fileName = Path.GetFileName(pathToFile);
-                            
-                            var mediaFile = File.ReadAllBytes(pathToFile);
+                        pChatMainControl.AddMessages(AddFileToMessage(mediaFile, fileName, pGroupOid, pChatMainControl.GetFirstMessage()));
+                        
+                        CollectionViewSource.GetDefaultView(pChatMainControl.ChatListBox.ItemsSource).Refresh();
 
-                            pChatMainControl.AddMessages(AddFileToMessage(mediaFile, fileName, pGroupOid, pChatMainControl.GetFirstMessage()));
-                            
-                            CollectionViewSource.GetDefaultView(pChatMainControl.ChatListBox.ItemsSource).Refresh();
+                        pChatMainControl.ChatListBox.Items.MoveCurrentToLast();
+                        pChatMainControl.ChatListBox.ScrollIntoView(pChatMainControl.ChatListBox.Items.CurrentItem);
 
-                            pChatMainControl.ChatListBox.Items.MoveCurrentToLast();
-                            pChatMainControl.ChatListBox.ScrollIntoView(pChatMainControl.ChatListBox.Items.CurrentItem);
-
-                            await SendMediaMessage(fileName, pGroupOid, mediaFile, null);
-                        }
+                        await SendMediaMessage(fileName, pGroupOid, mediaFile, null);
                     }
                 }
-                catch(Exception exception)
-                {
-                    ExceptionCallback?.Invoke(exception);
-                }
             }
             else
             {
@@ -825,85 +715,71 @@ namespace ChatController.HauptKlassen
         
         public void ShowProfilePicture(Contact currentContact)
         {
-            try
-            {
-                ShowPictureWindow(currentContact.Image, currentContact.Name);
-            }
-            catch (Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+            ShowPictureWindow(currentContact.Image, currentContact.Name);
         }
 
         public void ShowPictureWindow(ImageSource imageSource, string title)
         {
-            try
+            var imageWidth = Convert.ToInt32(imageSource.Width);
+            var imageHeight = Convert.ToInt32(imageSource.Height);
+
+            var imageAspectRatio = imageWidth / (double)imageHeight;
+
+            var primaryScreenWidth2 = SystemParameters.PrimaryScreenWidth;
+            var primaryScreenHeight2 = SystemParameters.PrimaryScreenHeight;
+
+            var windowMaxWidth = imageWidth;
+            var windowMaxHeight = imageHeight;
+
+            if(windowMaxWidth > .8 * primaryScreenWidth2 || windowMaxHeight > .8 * primaryScreenHeight2)
             {
-                var imageWidth = Convert.ToInt32(imageSource.Width);
-                var imageHeight = Convert.ToInt32(imageSource.Height);
-
-                var imageAspectRatio = imageWidth / (double)imageHeight;
-
-                var primaryScreenWidth2 = SystemParameters.PrimaryScreenWidth;
-                var primaryScreenHeight2 = SystemParameters.PrimaryScreenHeight;
-
-                var windowMaxWidth = imageWidth;
-                var windowMaxHeight = imageHeight;
-
-                if(windowMaxWidth > .8 * primaryScreenWidth2 || windowMaxHeight > .8 * primaryScreenHeight2)
+                if(primaryScreenWidth2 > primaryScreenHeight2)
                 {
-                    if(primaryScreenWidth2 > primaryScreenHeight2)
-                    {
-                        windowMaxHeight = (int)(.8 * primaryScreenHeight2);
-                        windowMaxWidth = (int)(windowMaxHeight * imageAspectRatio);
-                    }
-                    else
-                    {
-                        windowMaxWidth = (int)(.8 * primaryScreenWidth2);
-                        windowMaxHeight = (int)(windowMaxWidth * imageAspectRatio);
-                    }
+                    windowMaxHeight = (int)(.8 * primaryScreenHeight2);
+                    windowMaxWidth = (int)(windowMaxHeight * imageAspectRatio);
                 }
-
-                var maximumWindowSize = new System.Windows.Size(windowMaxWidth, windowMaxHeight);
-
-                var minHeight = 232 / imageAspectRatio;
-                var minWidth = 232d;
-
-                var window = new Window
+                else
                 {
-                    Title = title,
-                    MinHeight = minHeight,
-                    MinWidth = minWidth
-                };
-
-                var grid = new Grid
-                {
-                    Width = maximumWindowSize.Width,
-                    Height = maximumWindowSize.Height,
-                    MinHeight = minHeight,
-                    MinWidth = minWidth
-                };
-
-                var image = new System.Windows.Controls.Image
-                {
-                    Source = imageSource,
-                    Margin = new Thickness(0)
-                };
-
-                grid.Children.Clear();
-                grid.Children.Add(image);
-
-                window.SizeToContent = SizeToContent.WidthAndHeight;
-                window.Content = grid;
-                window.Margin = new Thickness(0);
-                window.WindowStartupLocation = WindowStartupLocation.CenterScreen;
-
-                window.ShowDialog();
+                    windowMaxWidth = (int)(.8 * primaryScreenWidth2);
+                    windowMaxHeight = (int)(windowMaxWidth * imageAspectRatio);
+                }
             }
-            catch(Exception exception)
+
+            var maximumWindowSize = new System.Windows.Size(windowMaxWidth, windowMaxHeight);
+
+            var minHeight = 232 / imageAspectRatio;
+            var minWidth = 232d;
+
+            var window = new Window
             {
-                ExceptionCallback?.Invoke(exception);
-            }
+                Title = title,
+                MinHeight = minHeight,
+                MinWidth = minWidth
+            };
+
+            var grid = new Grid
+            {
+                Width = maximumWindowSize.Width,
+                Height = maximumWindowSize.Height,
+                MinHeight = minHeight,
+                MinWidth = minWidth
+            };
+
+            var image = new System.Windows.Controls.Image
+            {
+                Source = imageSource,
+                Margin = new Thickness(0)
+            };
+
+            grid.Children.Clear();
+            grid.Children.Add(image);
+
+            window.SizeToContent = SizeToContent.WidthAndHeight;
+            window.Content = grid;
+            window.Margin = new Thickness(0);
+            window.WindowStartupLocation = WindowStartupLocation.CenterScreen;
+
+            window.ShowDialog();
         }
 
         public void ShowPicture(string originalImage, long groupId, Action<ImageSource, string> downloadCompletedCallback)
@@ -913,20 +789,13 @@ namespace ChatController.HauptKlassen
                 return;
             }
 
-            try
+            Utils.DownloadImageAsync(originalImage, $"group-{groupId}", CacheCategory.MessageAttachment, imageSource =>
             {
-                Utils.DownloadImageAsync(originalImage, $"group-{groupId}", CacheCategory.MessageAttachment, imageSource =>
-                {
-                    var splitName = originalImage.Split('/');
-                    var last = splitName.LastOrDefault();
+                var splitName = originalImage.Split('/');
+                var last = splitName.LastOrDefault();
 
-                    downloadCompletedCallback?.Invoke(imageSource, last ?? "Bild");
-                });
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+                downloadCompletedCallback?.Invoke(imageSource, last ?? "Bild");
+            });
         }
 
         public void ReloadGroupsAsync(Action<ChatGruppenDaten> callback)
@@ -951,22 +820,14 @@ namespace ChatController.HauptKlassen
 
         public List<Contact> UpdateContacts(ChatGruppenDaten chatDaten)
         {
-            try
+            _Contacts.Clear();
+            
+            if(!(chatDaten?.Response is null))
             {
-                _Contacts.Clear();
-                
-                if(!(chatDaten?.Response is null))
-                {
-                    _Contacts.AddRange(GenerateContactsFromServerResponse(chatDaten.Response.Groups.ToArray()));
-                }
+                _Contacts.AddRange(GenerateContactsFromServerResponse(chatDaten.Response.Groups.ToArray()));
+            }
 
-                return _Contacts;
-            }
-            catch(Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-                return null;
-            }
+            return _Contacts;
         }
 
         public List<Contact> GenerateContactsFromServerResponse(GroupInput[] pGroupInputs, bool pShouldUpdateLastTimeStamp = false)
@@ -1015,17 +876,16 @@ namespace ChatController.HauptKlassen
                     groupInput.Avatar,
                     key, groupInput.Users.ToDictionary(user => user.Oid, user => user.Picture)));
 
-                if(pShouldUpdateLastTimeStamp)
+                if(!pShouldUpdateLastTimeStamp || latestMessage?.Timestamp?.Date is null)
                 {
-                    if(!(latestMessage?.Timestamp?.Date is null))
-                    {
-                        var unixTimeStamp = DateTime.Parse(latestMessage.Timestamp.Date).GetUnixTimeStamp();
+                    continue;
+                }
 
-                        if(LastTimeStamp < unixTimeStamp)
-                        {
-                            LastTimeStamp = unixTimeStamp;
-                        }
-                    }
+                var unixTimeStamp = DateTime.Parse(latestMessage.Timestamp.Date).GetUnixTimeStamp();
+
+                if(LastTimeStamp < unixTimeStamp)
+                {
+                    LastTimeStamp = unixTimeStamp;
                 }
             }
 
@@ -1092,32 +952,25 @@ namespace ChatController.HauptKlassen
 
         public void DownloadFileAsync(string uri, string path, Action callback)
         {
-            try
+            var client = new RestClient(uri);
+            var request = new RestRequest();
+
+            request.AddHeader(Constants.Token, ChatDaten.AuthToken);
+            request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
+
+            client.ExecuteAsync(request, response =>
             {
-                var client = new RestClient(uri);
-                var request = new RestRequest();
-
-                request.AddHeader(Constants.Token, ChatDaten.AuthToken);
-                request.AddHeader(Constants.CustomerId, ChatDaten.Kundennummer);
-
-                client.ExecuteAsync(request, response =>
+                if(response.StatusCode == HttpStatusCode.OK)
                 {
-                    if(response.StatusCode == HttpStatusCode.OK)
-                    {
-                        response.RawBytes.SaveAs(path);
-                    }
-                    else
-                    {
-                        throw new Exception("Die Datei konnte nicht heruntergeladen werden.");
-                    }
+                    response.RawBytes.SaveAs(path);
+                }
+                else
+                {
+                    throw new Exception("Die Datei konnte nicht heruntergeladen werden.");
+                }
 
-                    callback?.Invoke();
-                });
-            }
-            catch (Exception exception)
-            {
-                ExceptionCallback?.Invoke(exception);
-            }
+                callback?.Invoke();
+            });
         }
 
         private bool _IsInBroadcastMode;

ChatController/HauptKlassen/Login.cs

@@ -83,38 +83,39 @@ namespace ChatController.HauptKlassen
         // Wird im BeWoPlaner benutzt
         public ChatDatenUebergabe AnmeldevorgangDurchFuehren()
         {
-            if(ServerErmittlung())
+            if(!ServerErmittlung())
             {
-                var dic = new Dictionary<string, string>
-                {
-                   { "username", _UserName},
-                   { "password", _Password},
-                   { "chatcode", _ChatCode}
-                };
-
-                VerbindeMitChatServer(dic);
-
-                if(_OwnchatVerbindungsaufbauOk)
-                {
-                    GetGroups();
-                }
-
-                if(_GruppeholenverbindungsaufbauOk)
-                {
-                    var maxUploadSize = GetMaiximumAllowedFileUploadSize(_AuthToken, _Tenant);
-
-                    return new ChatDatenUebergabe(_LoggedInUser, _AllGroups, ServerUrl, _AuthToken, _UserId, _Tenant, _ApiKey, maxUploadSize);
-                }
+                return null;
             }
 
-            return null;
+            var dic = new Dictionary<string, string>
+            {
+                { "username", _UserName},
+                { "password", _Password},
+                { "chatcode", _ChatCode}
+            };
+
+            VerbindeMitChatServer(dic);
+
+            if(_OwnchatVerbindungsaufbauOk)
+            {
+                GetGroups();
+            }
+
+            if(!_GruppeholenverbindungsaufbauOk)
+            {
+                return null;
+            }
+
+            var maxUploadSize = GetMaiximumAllowedFileUploadSize(_AuthToken, _Tenant);
+
+            return new ChatDatenUebergabe(_LoggedInUser, _AllGroups, ServerUrl, _AuthToken, _UserId, _Tenant, _ApiKey, maxUploadSize);
+
         }
 
         public void DoLoginAsync(Action<ChatDatenUebergabe> callback, Action<string> exceptionCallback)
         {
-            try
-            {
-                LookupServerUrlAsync(isConnectedWithServer =>
+            LookupServerUrlAsync(isConnectedWithServer =>
                 {
                     if(isConnectedWithServer)
                     {
@@ -139,163 +140,114 @@ namespace ChatController.HauptKlassen
                             errorMessage => { exceptionCallback?.Invoke(errorMessage); });
                     }
                 }, errorMessage => { exceptionCallback?.Invoke(errorMessage); });
-            }
-            catch(Exception)
-            {
-                callback?.Invoke(null);
-            }
         }
 
         public void LookupServerUrlAsync(Action<bool> callback, Action<string> exceptionCallback)
         {
-            try
+            if(!string.IsNullOrWhiteSpace(ServerUrl))
             {
-                if(!string.IsNullOrWhiteSpace(ServerUrl))
+                callback?.Invoke(false);
+                return;
+            }
+
+            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
+
+            var client = new RestClient(DictionaryServerUrl);
+            var request = new RestRequest(_Tenant);
+
+            client.ExecuteAsync(request, response =>
+            {
+                var lookupResult = JsonConvert.DeserializeObject<LookupResult>(response.Content);
+
+                _BaseUrl = lookupResult.Url;
+                ServerUrl = _BaseUrl;
+
+                var result = false;
+
+                switch(lookupResult.Status)
                 {
-                    callback?.Invoke(false);
-                    return;
+                    case 0:
+                        result = true;
+                        break;
+                    case 1:
+                        exceptionCallback?.Invoke("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.");
+                        break;
+                    case 2:
+                        exceptionCallback?.Invoke("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.");
+                        MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
+                        break;
                 }
 
-                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
-
-                var client = new RestClient(DictionaryServerUrl);
-                var request = new RestRequest(_Tenant);
-
-                client.ExecuteAsync(request, response =>
-                {
-                    var lookupResult = JsonConvert.DeserializeObject<LookupResult>(response.Content);
-
-                    _BaseUrl = lookupResult.Url;
-                    ServerUrl = _BaseUrl;
-
-                    var result = false;
-
-                    switch(lookupResult.Status)
-                    {
-                        case 0:
-                            result = true;
-                            break;
-                        case 1:
-                            exceptionCallback?.Invoke("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.");
-                            break;
-                        case 2:
-                            exceptionCallback?.Invoke("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.");
-                            MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
-                            break;
-                    }
-
-                    callback?.Invoke(result);
-                });
-            }
-            catch(Exception)
-            {
-                exceptionCallback?.Invoke("Fehler: Es konnte keine Verbindung aufgebaut werden.");
-            }
+                callback?.Invoke(result);
+            });
         }
 
         public bool ServerErmittlung()
         {
-            if (string.IsNullOrEmpty(ServerUrl))
+            if(string.IsNullOrEmpty(ServerUrl))
             {
+                var serverURl = DictionaryServerUrl + _Tenant;
+                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
+                var request = WebRequest.Create(serverURl);
+
+                request.Credentials = CredentialCache.DefaultCredentials;
+
+                var response = request.GetResponse();
+                var responseFromServer = Utils.ReadStream(response);
+
                 try
                 {
-                    var serverURl = DictionaryServerUrl + _Tenant;
-                    ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
-                    var request = WebRequest.Create(serverURl);
+                    var jsonDatentyp = JsonConvert.DeserializeObject<AuthenticationDataType1>(responseFromServer);
 
-                    request.Credentials = CredentialCache.DefaultCredentials;
-
-                    WebResponse response;
-
-                    try
+                    switch(jsonDatentyp.Status)
                     {
-                        response = request.GetResponse();
-                    }
-                    catch(Exception)
-                    {
-                        if (_ShouldShowMessageBox)
-                        {
-                            MessageBox.Show("Fehler: Es konnte keine Verbindung aufgebaut werden.", "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-                        }
+                        case 1:
+                            if (_ShouldShowMessageBox)
+                            {
+                                MessageBox.Show("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
+                            }
                         
-                        return false;
-                    }
-
-                    var responseFromServer = Utils.ReadStream(response);
-
-                    try
-                    {
-                        var jsonDatentyp = JsonConvert.DeserializeObject<AuthenticationDataType1>(responseFromServer);
-
-                        switch(jsonDatentyp.Status)
-                        {
-                            case 1:
-                                if (_ShouldShowMessageBox)
-                                {
-                                    MessageBox.Show("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
-                                }
-                            
-                                return false;
-                            case 2:
-                                if (_ShouldShowMessageBox)
-                                {
-                                    MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
-                                }
-                            
-                                return false;
-                        }
-
-                        _BaseUrl = jsonDatentyp.Url;
-                    }
-                    catch(Exception)
-                    {
-                        try
-                        {
-                            var jsonDatentyp = JsonConvert.DeserializeObject<AuthenticationDataType2>(responseFromServer);
-
-                            switch(jsonDatentyp.Status)
+                            return false;
+                        case 2:
+                            if (_ShouldShowMessageBox)
                             {
-                                case 1:
-                                    if (_ShouldShowMessageBox)
-                                    {
-                                        MessageBox.Show("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
-                                    }
-                                    
-                                    return false;
-                                case 2:
-                                    if (_ShouldShowMessageBox)
-                                    {
-                                        MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
-                                    }
-                                    
-                                    return false;
+                                MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
                             }
-
-                            _BaseUrl = jsonDatentyp.Url;
-                        }
-                        catch(Exception e)
-                        {
-                            if(_ShouldShowMessageBox)
-                            {
-                                MessageBox.Show("Fehler: " + e.Message, "ownChat Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-                            }
-                        }
+                        
+                            return false;
                     }
 
-                    response.Close();
-
-                    ServerUrl = _BaseUrl;
-                    return true;
+                    _BaseUrl = jsonDatentyp.Url;
                 }
-                catch(Exception e)
+                catch(Exception)
                 {
-                    if(_ShouldShowMessageBox)
+                    var jsonDatentyp = JsonConvert.DeserializeObject<AuthenticationDataType2>(responseFromServer);
+
+                    switch(jsonDatentyp.Status)
                     {
-                        MessageBox.Show("Fehler: " + e.Message, "ownChat Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
+                        case 1:
+                            if (_ShouldShowMessageBox)
+                            {
+                                MessageBox.Show("Fehler: Kundennummer unbekannt.\nBitte überprüfen Sie die Anmeldeinformationen.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
+                            }
+                            
+                            return false;
+                        case 2:
+                            if (_ShouldShowMessageBox)
+                            {
+                                MessageBox.Show("Der Diensttyp ist für die angegebene Kundennummer nicht definiert.", "ownChat Info", MessageBoxButton.OK, MessageBoxImage.Asterisk);
+                            }
+                            
+                            return false;
                     }
-                    
-                    return false;
+
+                    _BaseUrl = jsonDatentyp.Url;
                 }
+
+                response.Close();
+
+                ServerUrl = _BaseUrl;
+                return true;
             }
             
             return true;
@@ -303,104 +255,86 @@ namespace ChatController.HauptKlassen
 
         private void VerbindeMitChatServer(Dictionary<string, string> postparameter)
         {
-            try
+            var endurl = _BaseUrl + Constants.LoginWithChatCodeUrl; 
+
+            var requestBody = postparameter.Keys.Aggregate(string.Empty, (current, key) => current + HttpUtility.UrlEncode(key) + "=" + HttpUtility.UrlEncode(postparameter[key]) + "&");
+            
+            var client = new RestClient(endurl);
+            var request = new RestRequest(Method.POST);
+
+            request.AddHeader("content-type", "application/x-www-form-urlencoded");
+            request.AddParameter(Constants.CustomerId, _Tenant, ParameterType.HttpHeader);
+            request.AddParameter("application/x-www-form-urlencoded", requestBody, ParameterType.RequestBody);
+
+            var response = client.Post(request);
+
+            if(response.StatusCode == HttpStatusCode.OK)
             {
-                var endurl = _BaseUrl + Constants.LoginWithChatCodeUrl; 
+                Debug.WriteLine(response.Content);
+                var userDaten = JsonConvert.DeserializeObject<UserDaten>(response.Content);
 
-                var requestBody = postparameter.Keys.Aggregate(string.Empty, (current, key) => current + HttpUtility.UrlEncode(key) + "=" + HttpUtility.UrlEncode(postparameter[key]) + "&");
-                
-                var client = new RestClient(endurl);
-                var request = new RestRequest(Method.POST);
-
-                request.AddHeader("content-type", "application/x-www-form-urlencoded");
-                request.AddParameter(Constants.CustomerId, _Tenant, ParameterType.HttpHeader);
-                request.AddParameter("application/x-www-form-urlencoded", requestBody, ParameterType.RequestBody);
-
-                var response = client.Post(request);
-
-                if (response.StatusCode == HttpStatusCode.OK)
+                if(userDaten.Success)
                 {
-                    Debug.WriteLine(response.Content);
-                    var userDaten = JsonConvert.DeserializeObject<UserDaten>(response.Content);
+                    _AuthToken = userDaten.Response.User.Token;
+                    _UserId = userDaten.Response.User.Oid;
 
-                    if (userDaten.Success)
-                    {
-                        _AuthToken = userDaten.Response.User.Token;
-                        _UserId = userDaten.Response.User.Oid;
+                    Utils.AuthToken = _AuthToken;
+                    Utils.Tenant = _Tenant;
 
-                        Utils.AuthToken = _AuthToken;
-                        Utils.Tenant = _Tenant;
+                    _LoggedInUser = userDaten;
 
-                        _LoggedInUser = userDaten;
-
-                        _OwnchatVerbindungsaufbauOk = true;
-                    }
-                    else
-                    {
-                        if(!(userDaten.Error?.ChatCodeFailed is null))
-                        {
-                            if (_ShouldShowMessageBox)
-                            {
-                                MessageBox.Show("Fehler: " + userDaten.Error.ChatCodeFailed[0] + "\nBitte überprüfen Sie die Anmeldeinformationen.", "Info", MessageBoxButton.OK, MessageBoxImage.Error);
-                            }
-                        }
-                        else if(!(userDaten.Error?.LoginFailed is null))
-                        {
-                            if (_ShouldShowMessageBox)
-                            {
-                                MessageBox.Show("Fehler: " + userDaten.Error.LoginFailed[0] + "\nBitte überprüfen Sie die Anmeldeinformationen.", "Info", MessageBoxButton.OK, MessageBoxImage.Error);
-                            }
-                        }
-
-                        _OwnchatVerbindungsaufbauOk = false;
-                    }
+                    _OwnchatVerbindungsaufbauOk = true;
                 }
                 else
                 {
-                    MessageBox.Show(response.Content, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
+                    if(!(userDaten.Error?.ChatCodeFailed is null))
+                    {
+                        if(_ShouldShowMessageBox)
+                        {
+                            MessageBox.Show("Fehler: " + userDaten.Error.ChatCodeFailed[0] + "\nBitte überprüfen Sie die Anmeldeinformationen.", "Info", MessageBoxButton.OK, MessageBoxImage.Error);
+                        }
+                    }
+                    else if(!(userDaten.Error?.LoginFailed is null))
+                    {
+                        if(_ShouldShowMessageBox)
+                        {
+                            MessageBox.Show("Fehler: " + userDaten.Error.LoginFailed[0] + "\nBitte überprüfen Sie die Anmeldeinformationen.", "Info", MessageBoxButton.OK, MessageBoxImage.Error);
+                        }
+                    }
+
+                    _OwnchatVerbindungsaufbauOk = false;
                 }
             }
-            catch(Exception e)
+            else
             {
-                if(_ShouldShowMessageBox)
-                {
-                    MessageBox.Show("Fehler:" + e.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-                }
+                MessageBox.Show(response.Content, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
             }
         }
 
         private void GetGroups()
         {
-            try
+            var endurl = _BaseUrl + Constants.GetChatGroupsUrl;
+
+            var request = WebRequest.Create(endurl);
+
+            request.Credentials = CredentialCache.DefaultCredentials;
+            request.Headers[Constants.Token] = _AuthToken;
+            request.Headers[Constants.CustomerId] = _Tenant;
+
+            using(var response = request.GetResponse())
             {
-                var endurl = _BaseUrl + Constants.GetChatGroupsUrl;
+                var serverResponse = Utils.ReadStream(response);
 
-                var request = WebRequest.Create(endurl);
-
-                request.Credentials = CredentialCache.DefaultCredentials;
-                request.Headers[Constants.Token] = _AuthToken;
-                request.Headers[Constants.CustomerId] = _Tenant;
-
-                using (var response = request.GetResponse())
+                if(string.IsNullOrEmpty(serverResponse))
                 {
-                    var serverResponse = Utils.ReadStream(response);
-                    
-                    if (!string.IsNullOrEmpty(serverResponse))
-                    {
-                        var jsonDaten = JsonConvert.DeserializeObject<ChatGruppenDaten>(serverResponse);
-
-                        _AllGroups = jsonDaten;
-
-                        _GruppeholenverbindungsaufbauOk = true;
-                    }
-                }
-            }
-            catch (Exception e)
-            {
-                if (_ShouldShowMessageBox)
-                {
-                    MessageBox.Show("Fehler: " + e.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
+                    return;
                 }
+
+                var jsonDaten = JsonConvert.DeserializeObject<ChatGruppenDaten>(serverResponse);
+
+                _AllGroups = jsonDaten;
+
+                _GruppeholenverbindungsaufbauOk = true;
             }
         }
 
@@ -479,32 +413,25 @@ namespace ChatController.HauptKlassen
 
         public long GetMaiximumAllowedFileUploadSize(string pToken, string pCustomerId)
         {
-            long maximumFileSize;
-            
-            try
+            long maximumFileSize = 0L;
+
+            var endurl = ServerUrl + Constants.MaxUploadFileSizeUrl;
+
+            var request = WebRequest.Create(endurl);
+            request.Headers[Constants.Token] = pToken; 
+            request.Headers[Constants.CustomerId] = pCustomerId;
+
+            request.Credentials = CredentialCache.DefaultCredentials;
+            request.Proxy = null;
+
+            using (var response = request.GetResponse())
             {
-                var endurl = ServerUrl + Constants.MaxUploadFileSizeUrl;
+                var responseFromServer = Utils.ReadStream(response);
 
-                var request = WebRequest.Create(endurl);
-                request.Headers[Constants.Token] = pToken; 
-                request.Headers[Constants.CustomerId] = pCustomerId;
+                var definiti = new {file_upload_max_size = ""};
 
-                request.Credentials = CredentialCache.DefaultCredentials;
-                request.Proxy = null;
-
-                using (var response = request.GetResponse())
-                {
-                    var responseFromServer = Utils.ReadStream(response);
-
-                    var definiti = new {file_upload_max_size = ""};
-
-                    var jsonDatentyp = JsonConvert.DeserializeAnonymousType(responseFromServer, definiti);
-                    maximumFileSize = Convert.ToInt64(jsonDatentyp.file_upload_max_size);
-                }
-            }
-            catch (Exception e)
-            {
-                return 0;
+                var jsonDatentyp = JsonConvert.DeserializeAnonymousType(responseFromServer, definiti);
+                maximumFileSize = Convert.ToInt64(jsonDatentyp.file_upload_max_size);
             }
 
             return maximumFileSize;
@@ -522,7 +449,6 @@ namespace ChatController.HauptKlassen
 
             client.ExecuteAsync(request, response =>
             {
-                Debug.WriteLine("+++>Maximale Dateigröße erhalten");
                 var maxFileSizeAnonymous = JsonConvert.DeserializeAnonymousType(response.Content, new { file_upload_max_size = string.Empty });
 
                 var maxUploadFileSize = Convert.ToInt64(maxFileSizeAnonymous.file_upload_max_size);

ChatController/LoginControl.xaml.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.IO;
-using System.Reflection;
 using System.Runtime.CompilerServices;
 using System.Text;
 using System.Windows;
@@ -29,11 +28,13 @@ namespace ChatController
 
             set
             {
-                if (!Equals(_Benutzername, value))
+                if(Equals(_Benutzername, value))
                 {
-                    _Benutzername = value;
-                    OnPropertyChanged(nameof(UserName));
+                    return;
                 }
+
+                _Benutzername = value;
+                OnPropertyChanged(nameof(UserName));
             }
         }
 
@@ -50,11 +51,13 @@ namespace ChatController
 
             set
             {
-                if(!Equals(_ChatCode, value))
+                if(Equals(_ChatCode, value))
                 {
-                    _ChatCode = value;
-                    OnPropertyChanged(nameof(ChatCode));
+                    return;
                 }
+
+                _ChatCode = value;
+                OnPropertyChanged(nameof(ChatCode));
             }
         }
 
@@ -64,11 +67,13 @@ namespace ChatController
 
             set
             {
-                if(!Equals(_Kundennummer, value))
+                if(Equals(_Kundennummer, value))
                 {
-                    _Kundennummer = value;
-                    OnPropertyChanged(nameof(Tenant));
+                    return;
                 }
+
+                _Kundennummer = value;
+                OnPropertyChanged(nameof(Tenant));
             }
         }
 
@@ -104,24 +109,28 @@ namespace ChatController
 
         private void StartWaitingImmediately()
         {
-            if (_WaitLayer is null)
+            if(!(_WaitLayer is null))
             {
-                _WaitLayer = new ChatControlWaitLayer();
-                Panel.SetZIndex(_WaitLayer, int.MaxValue);
-                RootGrid.Children.Add(_WaitLayer);
-                _WaitLayer.RefreshUI();
+                return;
             }
+
+            _WaitLayer = new ChatControlWaitLayer();
+            Panel.SetZIndex(_WaitLayer, int.MaxValue);
+            RootGrid.Children.Add(_WaitLayer);
+            _WaitLayer.RefreshUI();
         }
 
         private void EndWaiting()
         {
             Dispatcher.BeginInvoke(DispatcherPriority.Normal, (Action) delegate
             {
-                if(!(_WaitLayer is null))
+                if(_WaitLayer is null)
                 {
-                    RootGrid.Children.Remove(_WaitLayer);
-                    _WaitLayer = null;
+                    return;
                 }
+
+                RootGrid.Children.Remove(_WaitLayer);
+                _WaitLayer = null;
             });
         }
 
@@ -129,7 +138,7 @@ namespace ChatController
         {
             try
             {
-                if (!string.IsNullOrWhiteSpace(_Kundennummer) && !string.IsNullOrWhiteSpace(_ChatCode) && !string.IsNullOrWhiteSpace(_Benutzername) && Password.Length > 0)
+                if(!string.IsNullOrWhiteSpace(_Kundennummer) && !string.IsNullOrWhiteSpace(_ChatCode) && !string.IsNullOrWhiteSpace(_Benutzername) && Password.Length > 0)
                 {
                     StartWaiting();
 
@@ -141,12 +150,14 @@ namespace ChatController
                         {
                             EndWaiting();
 
-                            if(chatDatenUebergabe != null)
+                            if(chatDatenUebergabe is null)
                             {
-                                AutosetDaten();
-
-                                OnLogin?.Invoke(chatDatenUebergabe);
+                                return;
                             }
+
+                            AutosetDaten();
+
+                            OnLogin?.Invoke(chatDatenUebergabe);
                         });
                     },
                         errorMessage =>
@@ -164,9 +175,8 @@ namespace ChatController
                     MessageBox.Show("Bitte alle Felder ausfüllen!", "Info", MessageBoxButton.OK);
                 }
             }
-            catch (Exception exception)
+            finally
             {
-                MessageBox.Show("Fehler: " + exception.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
                 EndWaiting();
                 Cursor = Cursors.Arrow;
             }
@@ -174,86 +184,64 @@ namespace ChatController
 
         private void LoadTenantAndChatCodeFromFile()
         {
-            try
+            if(File.Exists(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
             {
-                if(File.Exists(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
+                var lines = new List<string>();
+                using(var streamReader = new StreamReader(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), true))
                 {
-                    var lines = new List<string>();
-                    using(var streamReader = new StreamReader(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), true))
-                    {
-                        string line;
+                    string line;
 
-                        while(!((line = streamReader.ReadLine()) is null))
+                    while(!((line = streamReader.ReadLine()) is null))
+                    {
+                        var encodedTextBytes = Convert.FromBase64String(line);
+
+                        var plainText = Encoding.UTF8.GetString(encodedTextBytes);
+
+                        lines.Add(plainText);
+                    }
+                }
+
+                if(lines.Count == 2)
+                {
+                    _Kundennummer = lines[0];
+                    _ChatCode = lines[1];
+                }
+            }
+
+            #if DEBUG
+            var debugFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "debug-info.txt");
+            if (File.Exists(debugFile))
+            {
+                using(var streamReader2 = new StreamReader(debugFile, true))
+                {
+                    string line;
+
+                    var counter = 0;
+
+                    while(!((line = streamReader2.ReadLine()) is null))
+                    {
+                        if(counter == 0)
                         {
                             var encodedTextBytes = Convert.FromBase64String(line);
 
                             var plainText = Encoding.UTF8.GetString(encodedTextBytes);
 
-                            lines.Add(plainText);
+                            UserName = plainText;
                         }
-                    }
-
-                    if(lines.Count == 2)
-                    {
-                        _Kundennummer = lines[0];
-                        _ChatCode = lines[1];
-                    }
-                }
-
-                #if DEBUG
-                var debugFile = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "debug-info.txt");
-                if (File.Exists(debugFile))
-                {
-                    using(var streamReader2 = new StreamReader(debugFile, true))
-                    {
-                        string line;
-
-                        var counter = 0;
-
-                        while(!((line = streamReader2.ReadLine()) is null))
+                        else if(counter == 1)
                         {
-                            if(counter == 0)
-                            {
-                                try
-                                {
-                                    var encodedTextBytes = Convert.FromBase64String(line);
+                            var encodedTextBytes = Convert.FromBase64String(line);
 
-                                    var plainText = Encoding.UTF8.GetString(encodedTextBytes);
+                            var plainText = Encoding.UTF8.GetString(encodedTextBytes);
 
-                                    UserName = plainText;
-                                }
-                                catch (Exception)
-                                {
-                                    MessageBox.Show("Der Zeile muss im Base64-Format kodiert sein.", "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-                                }
-                                
-                            }
-                            else if(counter == 1)
-                            {
-                                try
-                                {
-                                    var encodedTextBytes = Convert.FromBase64String(line);
-
-                                    var plainText = Encoding.UTF8.GetString(encodedTextBytes);
-
-                                    Password = plainText;
-                                }
-                                catch (Exception)
-                                {
-                                    MessageBox.Show("Der Zeile muss im Base64-Format kodiert sein.", "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
-                                }
-                            }
-
-                            counter++;
+                            Password = plainText;
                         }
+
+                        counter++;
                     }
                 }
-                #endif
-            }
-            catch(Exception e)
-            {
-                MessageBox.Show("Fehler: \n" + e.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
             }
+            #endif
         }
 
         private void LeseDateiFallsVorhanden()
@@ -263,63 +251,46 @@ namespace ChatController
 
         private void AutosetDaten()
         {
-            try
+            if(File.Exists(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
             {
-                if(File.Exists(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
-                {
-                    File.SetAttributes(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), FileAttributes.Normal);
-                    File.Delete(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName));
-                }
-
-                using(var streamWriter = new StreamWriter(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
-                {
-                    Encoding utf8Encoding = new UTF8Encoding();
-                    var tenantBytes = utf8Encoding.GetBytes(_Kundennummer);
-                    var encodedTenant = Convert.ToBase64String(tenantBytes);
-
-                    var chatCodeBytes = utf8Encoding.GetBytes(_ChatCode);
-                    var encodedChatCode = Convert.ToBase64String(chatCodeBytes);
-
-                    streamWriter.WriteLine(encodedTenant);
-                    streamWriter.WriteLine(encodedChatCode);
-
-                    File.SetAttributes(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), FileAttributes.ReadOnly);
-                }
+                File.SetAttributes(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), FileAttributes.Normal);
+                File.Delete(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName));
             }
-            catch (Exception e)
+
+            using(var streamWriter = new StreamWriter(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName)))
             {
-                MessageBox.Show("Fehler: \n" + e.Message, "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
+                Encoding utf8Encoding = new UTF8Encoding();
+                var tenantBytes = utf8Encoding.GetBytes(_Kundennummer);
+                var encodedTenant = Convert.ToBase64String(tenantBytes);
+
+                var chatCodeBytes = utf8Encoding.GetBytes(_ChatCode);
+                var encodedChatCode = Convert.ToBase64String(chatCodeBytes);
+
+                streamWriter.WriteLine(encodedTenant);
+                streamWriter.WriteLine(encodedChatCode);
+
+                File.SetAttributes(Path.Combine(GetAndCreateUserAppDataPath(), Constants.TenantAndChatCodeFileName), FileAttributes.ReadOnly);
             }
         }
 
         private static string GetAndCreateUserAppDataPath()
         {
-            try
+            var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            var companyFilePath = Path.Combine(localAppData, "ownSoft");
+
+            if(!Directory.Exists(companyFilePath))
             {
-                var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-                var companyFilePath = Path.Combine(localAppData, "ownSoft");
-
-                if(!Directory.Exists(companyFilePath))
-                {
-                    Directory.CreateDirectory(companyFilePath);
-                }
-
-                var bewoFilePath = Path.Combine(companyFilePath, "OwnChat");
-
-                if(!Directory.Exists(bewoFilePath))
-                {
-                    Directory.CreateDirectory(bewoFilePath);
-                }
-
-                return bewoFilePath;
+                Directory.CreateDirectory(companyFilePath);
             }
-            catch (Exception ex)
+
+            var bewoFilePath = Path.Combine(companyFilePath, "OwnChat");
+
+            if(!Directory.Exists(bewoFilePath))
             {
-                MessageBox.Show(
-                    "Fehler beim Anlegen des Anwendungsordners. Sie besitzen nicht die erforderlichen Rechte, bitte wenden Sie sich an Ihren Systemadministrator.\n" +
-                    ex.Message, "BeWoPlaner", MessageBoxButton.OK, MessageBoxImage.Exclamation);
+                Directory.CreateDirectory(bewoFilePath);
             }
-            return Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+
+            return bewoFilePath;
         }
 
         public void Login()

ChatController/Utilities/FileUtils.cs

@@ -12,122 +12,115 @@ namespace ChatController.Utilities
     {
         public static string ScaleImage(string pFile, string pFormat, long maxUploadSize)
         {
-            try
-            {
-                var isImageFile = Constants.ImageFileExtensions.Contains(Path.GetExtension(pFile).ToUpperInvariant());
+            var isImageFile = Constants.ImageFileExtensions.Contains(Path.GetExtension(pFile).ToUpperInvariant());
 
-                if(!isImageFile)
-                {
-                    return pFile;
-                }
-
-                byte[] mediaFile;
-                using(Stream reader = File.OpenRead(pFile))
-                {
-                    mediaFile = Utils.ReadFully(reader);
-                }
-
-                var memoryStream = new MemoryStream(mediaFile);
-                var image = Image.FromStream(memoryStream);
-
-                float width, height;
-
-                if(image.Height < image.Width)
-                {
-                    if(image.Height > 1080)
-                    {
-                        var factor = (float)image.Height / 1080;
-
-                        height = 1080;
-
-                        width = image.Width / factor;
-                    }
-                    else
-                    {
-                        return pFile;
-                    }
-                }
-                else if(image.Height < 1080 && image.Width < 1080)
-                {
-                    return pFile;
-                }
-                else
-                {
-                    if(image.Width > 1080)
-                    {
-                        var factor = (float)image.Width / 1080;
-
-                        width = 1080;
-
-                        height = image.Height / factor;
-                    }
-                    else
-                    {
-                        return pFile;
-                    }
-                }
-
-                var scaledBitmap = new Bitmap(image, new Size((int)width, (int)height));
-
-                const int orientationId = 0x0112;
-
-                if(image.PropertyIdList.Contains(orientationId))
-                {
-                    var item = image.GetPropertyItem(orientationId);
-
-                    scaledBitmap.SetPropertyItem(item);
-                }
-
-                using(var graphics = Graphics.FromImage(image))
-                {
-                    graphics.Clear(Color.Transparent);
-
-                    graphics.InterpolationMode = InterpolationMode.Low;
-
-                    graphics.DrawImage(scaledBitmap, (int)width, (int)height);
-                }
-
-                // tmp_img_owch_
-                var filePath = $"{Path.GetTempPath()}{Guid.NewGuid()}_tmp_img_owch{pFormat}";
-
-                if(pFormat.Equals(".JPG") || pFormat.Equals(".JPE") || pFormat.Equals(".JPEG") || pFormat.Equals(".BMP"))
-                {
-                    scaledBitmap.Save(filePath, ImageFormat.Jpeg);
-                }
-                else if(pFormat.Equals(".PNG"))
-                {
-                    scaledBitmap.Save(filePath, ImageFormat.Png);
-                }
-                else if(pFormat.Equals(".GIF"))
-                {
-                    scaledBitmap.Save(filePath, ImageFormat.Gif);
-                }
-
-                if(File.Exists(filePath))
-                {
-                    var fileInfo = new FileInfo(filePath);
-                    var fileInfoLength = fileInfo.Length;
-
-                    if(maxUploadSize < fileInfoLength)
-                    {
-                        File.Delete(filePath);
-                        return string.Empty;
-                    }
-                }
-                else
-                {
-                    return string.Empty;
-                }
-
-                memoryStream.Dispose();
-                memoryStream.Close();
-
-                return filePath;
-            }
-            catch(Exception exception)
+            if(!isImageFile)
             {
                 return pFile;
             }
+
+            byte[] mediaFile;
+            using(Stream reader = File.OpenRead(pFile))
+            {
+                mediaFile = Utils.ReadFully(reader);
+            }
+
+            var memoryStream = new MemoryStream(mediaFile);
+            var image = Image.FromStream(memoryStream);
+
+            float width, height;
+
+            if(image.Height < image.Width)
+            {
+                if(image.Height > 1080)
+                {
+                    var factor = (float)image.Height / 1080;
+
+                    height = 1080;
+
+                    width = image.Width / factor;
+                }
+                else
+                {
+                    return pFile;
+                }
+            }
+            else if(image.Height < 1080 && image.Width < 1080)
+            {
+                return pFile;
+            }
+            else
+            {
+                if(image.Width > 1080)
+                {
+                    var factor = (float)image.Width / 1080;
+
+                    width = 1080;
+
+                    height = image.Height / factor;
+                }
+                else
+                {
+                    return pFile;
+                }
+            }
+
+            var scaledBitmap = new Bitmap(image, new Size((int)width, (int)height));
+
+            const int orientationId = 0x0112;
+
+            if(image.PropertyIdList.Contains(orientationId))
+            {
+                var item = image.GetPropertyItem(orientationId);
+
+                scaledBitmap.SetPropertyItem(item);
+            }
+
+            using(var graphics = Graphics.FromImage(image))
+            {
+                graphics.Clear(Color.Transparent);
+
+                graphics.InterpolationMode = InterpolationMode.Low;
+
+                graphics.DrawImage(scaledBitmap, (int)width, (int)height);
+            }
+
+            // tmp_img_owch_
+            var filePath = $"{Path.GetTempPath()}{Guid.NewGuid()}_tmp_img_owch{pFormat}";
+
+            if(pFormat.Equals(".JPG") || pFormat.Equals(".JPE") || pFormat.Equals(".JPEG") || pFormat.Equals(".BMP"))
+            {
+                scaledBitmap.Save(filePath, ImageFormat.Jpeg);
+            }
+            else if(pFormat.Equals(".PNG"))
+            {
+                scaledBitmap.Save(filePath, ImageFormat.Png);
+            }
+            else if(pFormat.Equals(".GIF"))
+            {
+                scaledBitmap.Save(filePath, ImageFormat.Gif);
+            }
+
+            if(File.Exists(filePath))
+            {
+                var fileInfo = new FileInfo(filePath);
+                var fileInfoLength = fileInfo.Length;
+
+                if(maxUploadSize < fileInfoLength)
+                {
+                    File.Delete(filePath);
+                    return string.Empty;
+                }
+            }
+            else
+            {
+                return string.Empty;
+            }
+
+            memoryStream.Dispose();
+            memoryStream.Close();
+
+            return filePath;
         }
         
         public static bool CheckFileSize(string pathToFile, long maxFileSize)

ChatController/Utilities/Utils.cs

@@ -213,31 +213,22 @@ namespace ChatController.Utilities
 
         public static string GetAndCreateUserAppDataPath()
         {
-            try
+            var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+            var companyFilePath = Path.Combine(localAppData, Resource.CompanyName);
+
+            if(!Directory.Exists(companyFilePath))
             {
-                var localAppData = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
-                var companyFilePath = Path.Combine(localAppData, Resource.CompanyName);
-
-                if(!Directory.Exists(companyFilePath))
-                {
-                    Directory.CreateDirectory(companyFilePath);
-                }
-
-                var bewoFilePath = Path.Combine(companyFilePath, Resource.ApplicationFolderName);
-
-                if(!Directory.Exists(bewoFilePath))
-                {
-                    Directory.CreateDirectory(bewoFilePath);
-                }
-
-                return bewoFilePath;
-            }
-            catch(Exception exception)
-            {
-                MessageBox.Show("Fehler beim Anlegen des Anwendungsordners. Sie besitzen nicht die erforderlichen Rechte, bitte wenden Sie sich an Ihren Systemadministrator.\n" + exception.Message, "BeWoPlaner", MessageBoxButton.OK, MessageBoxImage.Exclamation);
+                Directory.CreateDirectory(companyFilePath);
             }
 
-            return Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
+            var bewoFilePath = Path.Combine(companyFilePath, Resource.ApplicationFolderName);
+
+            if(!Directory.Exists(bewoFilePath))
+            {
+                Directory.CreateDirectory(bewoFilePath);
+            }
+
+            return bewoFilePath;
         }
 
         public static string GenerateTempName()
@@ -253,18 +244,10 @@ namespace ChatController.Utilities
 
         public static byte[] ImageToByteArray(Image pImage)
         {
-            try
+            using(var memoryStream = new MemoryStream())
             {
-                using(var memoryStream = new MemoryStream())
-                {
-                    pImage.Save(memoryStream, ImageFormat.Bmp);
-                    return memoryStream.ToArray();
-                }
-            }
-            catch(Exception exception)
-            {
-                MessageBox.Show("Fehler: " + exception.Message, "Fehler", MessageBoxButton.OK);
-                return null;
+                pImage.Save(memoryStream, ImageFormat.Bmp);
+                return memoryStream.ToArray();
             }
         }
 

PrototypChat/App.xaml

@@ -2,6 +2,7 @@
              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:local="clr-namespace:ownChat"
+             DispatcherUnhandledException="App_DispatcherUnhandledException"
              StartupUri="LoginMaske.xaml">
     <Application.Resources>
          

PrototypChat/App.xaml.cs

@@ -1,6 +1,14 @@
-namespace ownChat
+using System.Windows.Threading;
+
+namespace ownChat
 {
     public partial class App
     {
+        private void App_DispatcherUnhandledException(object sender, DispatcherUnhandledExceptionEventArgs args)
+        {
+            new ExceptionWindow(args.Exception) { Owner = MainWindow }.Show();
+
+            args.Handled = true;
+        }
     }
 }

PrototypChat/ExceptionWindow.xaml

@@ -0,0 +1,12 @@
+<Window x:Class="ownChat.ExceptionWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:chatController="clr-namespace:ChatController;assembly=ChatController"
+        mc:Ignorable="d" WindowStartupLocation="CenterOwner"
+        Title="Es ist ein Fehler aufgetreten" Height="450" Width="800">
+    <Grid>
+        <chatController:ExceptionViewControl x:Name="ExceptionViewControl" OkButtonClicked="ExceptionViewControl_OnOkButtonClicked" />
+    </Grid>
+</Window>

PrototypChat/ExceptionWindow.xaml.cs

@@ -0,0 +1,18 @@
+using System;
+
+namespace ownChat
+{
+    public partial class ExceptionWindow
+    {
+        public ExceptionWindow(Exception exception)
+        {
+            InitializeComponent();
+            ExceptionViewControl.Exception = exception;
+        }
+
+        private void ExceptionViewControl_OnOkButtonClicked(object sender, EventArgs e)
+        {
+            Close();
+        }
+    }
+}

PrototypChat/MainWindow.xaml.cs

@@ -17,6 +17,9 @@ namespace ownChat
         {
             InitializeComponent();
 
+            var currentDomain = AppDomain.CurrentDomain;
+            currentDomain.UnhandledException += ExceptionHandler;
+
             ChatMainControl.ContainingWindow = this;
 
             ChatMainControl.InitMitChatdaten(x);
@@ -24,6 +27,13 @@ namespace ownChat
             _EmojiView = new ChatEmojisView(ChatMainControl);
         }
 
+        private void ExceptionHandler(object sender, UnhandledExceptionEventArgs args)
+        {
+            var exception = (Exception)args.ExceptionObject;
+
+            new ExceptionWindow(exception) { Owner = this }.Show();
+        }
+
         private void ChatMainControl_OnOnEmojii(System.Windows.Controls.Button emojiButton)
         {
             _EmojiView.Visibility = Visibility.Visible;
@@ -31,11 +41,13 @@ namespace ownChat
             var pointToScreen = emojiButton.PointToScreen(new Point(0, 0));
             var presentationSource = PresentationSource.FromVisual(emojiButton);
 
-            if(presentationSource?.CompositionTarget != null)
+            if(presentationSource?.CompositionTarget == null)
             {
-                _EmojiView.Top = pointToScreen.Y / presentationSource.CompositionTarget.TransformToDevice.M22 - _EmojiView.Height - 5;
-                _EmojiView.Left = pointToScreen.X / presentationSource.CompositionTarget.TransformToDevice.M11 - 270;
+                return;
             }
+
+            _EmojiView.Top = pointToScreen.Y / presentationSource.CompositionTarget.TransformToDevice.M22 - _EmojiView.Height - 5;
+            _EmojiView.Left = pointToScreen.X / presentationSource.CompositionTarget.TransformToDevice.M11 - 270;
         }
 
         private void MainWindow_OnClosed(object sender, EventArgs e)

PrototypChat/PrototypChat.csproj

@@ -105,6 +105,10 @@
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
     </Page>
+    <Page Include="ExceptionWindow.xaml">
+      <SubType>Designer</SubType>
+      <Generator>MSBuild:Compile</Generator>
+    </Page>
     <Page Include="LoginMaske.xaml">
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
@@ -117,6 +121,9 @@
       <DependentUpon>App.xaml</DependentUpon>
       <SubType>Code</SubType>
     </Compile>
+    <Compile Include="ExceptionWindow.xaml.cs">
+      <DependentUpon>ExceptionWindow.xaml</DependentUpon>
+    </Compile>
     <Compile Include="LoginMaske.xaml.cs">
       <DependentUpon>LoginMaske.xaml</DependentUpon>
     </Compile>