[FancyZones Editor] Crash when changing between zone layouts: refactoring (#12815)

src/modules/fancyzones/editor/FancyZonesEditor/MainWindow.xaml.cs

@@ -30,7 +30,6 @@ namespace FancyZonesEditor
 
         private ContentDialog _openedDialog;
         private TextBlock _createLayoutAnnounce;
-        private bool _openingDialog = false; // Is the dialog being opened.
 
         public int WrapPanelItemSize { get; set; } = DefaultWrapPanelItemSize;
 
@@ -281,11 +280,11 @@ namespace FancyZonesEditor
         private async void EditLayout_Click(object sender, RoutedEventArgs e)
         {
             // Avoid trying to open the same dialog twice.
-            if (!_openingDialog)
+            if (_openedDialog != null)
-            {
-                _openingDialog = true;
-                try
             {
+                return;
+            }
+
             var dataContext = ((FrameworkElement)sender).DataContext;
             Select((LayoutModel)dataContext);
 
@@ -300,13 +299,6 @@ namespace FancyZonesEditor
 
             await EditLayoutDialog.ShowAsync();
         }
-                catch
-                {
-                    _openingDialog = false;
-                    throw;
-                }
-            }
-        }
 
         private void EditZones_Click(object sender, RoutedEventArgs e)
         {
@@ -454,7 +446,6 @@ namespace FancyZonesEditor
 
         private void Dialog_Closed(ContentDialog sender, ContentDialogClosedEventArgs args)
         {
-            _openingDialog = false;
             _openedDialog = null;
         }