CPSplitView enable us to get more space in the web browser.
CPSplitView generates two notifications.
-(void) splitViewDidResizeSubviews:(CPNotification)notification -(void) splitViewWillResizeSubviews:(CPNotification)notification
If you read the source of the framework, you can search for delegate methods. You can find some like the following.
-(CGRect)splitView:(CPSplitView)splitView effectiveRect:(CGRect)effectiveRect forDrawnRect:(CGRect)drawnRect ofDividerAtIndex:(int)anIndex -(CGRect) splitView:(CPSplitView)splitView additionalEffectiveRectOfDividerAtIndex:(int)anIndex
Well you can read the code of the framework and find some ideas ;-). Image loading should be a good idea.
If you'd like to see the complete code listing from the tutorial, you can download it all in a single file: Tutorial3.zip. The web application is available online: Tutorial3