Wpf event not bubbling

Question

Here is my XAML:

Answer 1

Microsoft wrote a very nice explanation Routed Events Overview

exactly the same thing will happen with MouseUpand PreviewMouseUp events in your case the e.Handled = (bool) chkhandle.IsChecked; stops the routing of the event.

if you want to debug the events you can use Snoop it will illustrate very nicely which events happened on which objects and who handled them.