Fixed potential bug sources and missing handler

- Fixed a potential bug that could have caused problems when actions
were cancelled
- Fixed a bug that made it possible to start the update process multiple
times using the integrated UpdaterUI
- Added forgotten event handler that should have reported failed
downloads, but consecutively did not
- Fixed a bug that fired the Finished-event, even if the download of the
packages failed
- Improved code and made it fully working now

nUpdate/UI/Dialogs/UpdateDownloadDialog.cs

@@ -107,8 +107,6 @@ private void UpdateDownloadDialog_Load(object sender, EventArgs e)
             Icon = _appIcon;
         }
 
-        #region TAP
-
         public void ShowModalDialog(object dialogResultReference)
         {
             ((DialogResultReference)dialogResultReference).DialogResult = ShowDialog();
@@ -119,6 +117,8 @@ public void CloseDialog(object state)
             Close();
         }
 
+        #region TAP
+
         public void Fail(Exception ex)
         {
             Invoke(new Action(() => Popup.ShowPopup(this, SystemIcons.Error,
@@ -155,6 +155,14 @@ public void ProgressChanged(object sender, UpdateDownloadProgressChangedEventArg
             }
         }
 
+        public void Failed(object sender, FailedEventArgs e)
+        {
+            Invoke(new Action(() => Popup.ShowPopup(this, SystemIcons.Error,
+                "Error while downloading the update package.",
+                e.Exception.InnerException ?? e.Exception, PopupButtons.Ok)));
+            DialogResult = DialogResult.Cancel;
+        }
+
         public void Finished(object sender, EventArgs e)
         {
             DialogResult = DialogResult.OK;

nUpdate/UI/Dialogs/UpdateSearchDialog.cs

@@ -84,9 +84,9 @@ public void Fail(Exception ex)
                 PopupButtons.Ok)));
         }
 
-        public void ShowModalDialog(object state)
+        public void ShowModalDialog(object dialogResultReference)
         {
-            ShowDialog();
+            ((DialogResultReference)dialogResultReference).DialogResult = ShowDialog();
         }
 
         public void CloseDialog(object state)

nUpdate/Updating/UpdateManager.cs

@@ -413,7 +413,7 @@ public void DownloadPackages()
                         }
                     }
                 }
-                catch (Exception)
+                finally
                 {
                     if (webResponse != null)
                         webResponse.Close();
@@ -442,7 +442,8 @@ private void DownloadTaskCompleted(Task task)
             var exception = task.Exception;
             if (exception != null)
                 OnUpdateDownloadFailed(exception.InnerException ?? exception);
-            OnUpdateDownloadFinished(this, EventArgs.Empty);
+            else
+                OnUpdateDownloadFinished(this, EventArgs.Empty);
         }
 
 #if PROVIDE_TAP

nUpdate/Updating/UpdaterUi.cs

@@ -120,6 +120,7 @@ public void ShowUserInterface()
             if (_isTaskRunning)
                 return;
 
+            _isTaskRunning = true;
             var searchDialog = new UpdateSearchDialog {LanguageName = _updateManager.LanguageCulture.Name};
             searchDialog.CancelButtonClicked += UpdateSearchDialogCancelButtonClick;
 
@@ -140,10 +141,10 @@ public void ShowUserInterface()
 
 #if PROVIDE_TAP
 
+
             // TAP
             TaskEx.Run(async delegate
             {
-                _isTaskRunning = true;
                 if (!UseHiddenSearch)
                     _context.Post(searchDialog.ShowModalDialog, null);
 
@@ -248,13 +249,15 @@ public void ShowUserInterface()
                 _isTaskRunning = false;
             });
 
+
 #else
             //EAP
             _updateManager.UpdateSearchFinished += SearchFinished;
             _updateManager.UpdateSearchFinished += searchDialog.Finished;
             _updateManager.UpdateSearchFailed += searchDialog.Failed;
             _updateManager.PackagesDownloadProgressChanged += downloadDialog.ProgressChanged;
             _updateManager.PackagesDownloadFinished += downloadDialog.Finished;
+            _updateManager.PackagesDownloadFailed += downloadDialog.Failed;
 
             Task.Factory.StartNew(() =>
             {
@@ -263,8 +266,9 @@ public void ShowUserInterface()
                 {
                     var searchDialogResultReference = new DialogResultReference();
                     _context.Send(searchDialog.ShowModalDialog, searchDialogResultReference);
-                    if (searchDialogResultReference.DialogResult == DialogResult.OK)
-                        _context.Send(searchDialog.CloseDialog, null);
+                    _context.Send(searchDialog.CloseDialog, null);
+                    if (searchDialogResultReference.DialogResult == DialogResult.Cancel)
+                        return;
                 }
                 else
                 {
@@ -326,6 +330,7 @@ public void ShowUserInterface()
                         PopupButtons.Ok), null);
                 else
                     _updateManager.InstallPackage();
+                _isTaskRunning = false;
             });
 #endif
         }