[Solved] RadExpander and disappeared PreviewExpanded

[Jaroslav Půbal]

Hello great Telerik support!
I have probably one bug in RadExpander and PreviewCollapsed and PreviewExpanded events.

Generally we want to be able stop RadExpander from collapsing or expanding.

private void RadExpander_PreviewExpanded(object sender, Telerik.Windows.RadRoutedEventArgs e)
{
    e.Handled = true; //some logic
    Debug.WriteLine("RadExpander_PreviewExpanded");
}
private void RadExpander_PreviewCollapsed(object sender, Telerik.Windows.RadRoutedEventArgs e)
{
    e.Handled = true; //some logic
    Debug.WriteLine("RadExpander_PreviewCollapsed");
}

This is generally working, but no really.

When Preview method once stop action (e.handled=true) then second invocation of Preview never happens.
So if I 4x click on RadExpander only two lines of "RadExpander_PreviewExpanded" will be in the Output window.

Always one event proceed and one disappear.

[Petar Mladenov]

Hello Jaroslav Půbal,

I was unable to reproduce such issue in my environment. You can check out the attached project and the captured video and let me know if I have missed something. Thank you in advance for your cooperation.

Kind regards,
Petar Mladenov
the Telerik team

[Jaroslav Půbal]

Hello,
I do an extensive research :-) with IE9, IE8, Chrome, SL4 and SL5.

I finally found that this happens only when running in debug in Visual Studio.

So for me this is OK.

(My enviroment is IE9 with SL5 beta)