Этап 9

Minint/ViewModels/EditorViewModel.cs

@@ -113,6 +113,12 @@ public partial class EditorViewModel : ViewModelBase
         SyncLayersAndCanvas(doc);
     }
 
+    /// <summary>
+    /// Re-syncs the Documents observable collection after an external modification
+    /// to Container.Documents (e.g. pattern generation adding a document).
+    /// </summary>
+    public void SyncAfterExternalChange() => SyncDocumentsList();
+
     private void SyncDocumentsList()
     {
         Documents.Clear();