If you mean the bottom-right of the view disappears, it happens because setZoomFactor zooms at the top-left point (the current scroll position). If you'd like to zoom at the center or the bottom-right, you could use the zoomToRect method instead, where you calculate an appropriate rectangle from the currently visible part of the diagram. You can find the visible rectangle in diagram coordinate by calling view.deviceToDoc(view.getVisibleRect()).

I hope that helps,
Stoyan

I tried the zoomToFit and it works better, however there is a brief flash of a rectangle on the Overview panel that is of a different size before the rectangle is reset to the size requested.

I still have a problem of losing the x,y location of the rectangle, i think when the width or height exceed the extent of the diagram. If you have a workaround for that, it would be helpful. Thanks

Zoom works now however the flashing rectangle problem on the overview is still there despite using suspendRepaint and resumeRepaint

overview.suspendRepaint();




Rectangle2D.Float rect = diagramView.deviceToDoc(diagramView.getVisibleRect());




rect.setRect(rect.x-rect.width/2, rect.y-rect.height/2, rect.width*2, rect.height*2);




diagramView.zoomToFit(rect);




overview.resumeRepaint(); 

I sent in a sample problem. Please let me know how I can be notified when its fixed. Thanks

Thanks for the sample project; we can see the problem now. Our developer investigated, and found that when the overview and DiagramView are in the same frame, Swing calls events in this order:

repaint overview -> zoomed DiagramView size set -> repaint overview

It seems the events are raised asynchronously after zoomToFit completes, so calling suspendRepaint does not help. Since the tracking rectangle shows the ratio between the full size of the zoomed DiagramView and its visible area, the paint events from before and after the size change show different rectangles and you get the flickering effect.

If the overview is in a different frame as in our test app, its paintComponent method does not get called before the view is actually resized so I only saw the end result without flickering.

We'll try to modify our code to use the Diagram size and zoom level instead of the DiagramView's current size to avoid that problem.

Stoyan

This version should avoid repainting the rectangle twice from zoomToFit:
https://mindfusion.eu/_temp/jdiag_ovw.zip

I hope that helps,
Stoyan