Since the DrawingIsland is stored in the ContentIsland's AppData, we must ensure that the ContentIsland is Closed in order to break the memory reference cycle. While in this particular case we could rely on the ContentIsland being closed implicitly when the window is torn down, I think it is better practice to explicitly call Close() during the Window.Closing event.
Since the DrawingIsland is stored in the ContentIsland's AppData, we must ensure that the ContentIsland is Closed in order to break the memory reference cycle. While in this particular case we could rely on the ContentIsland being closed implicitly when the window is torn down, I think it is better practice to explicitly call Close() during the Window.Closing event.