[Solved] RadCallout arrow does not point to placementTarget when popup is constrained by screen edges

[Alina]

Hi all,

I am working with RadCallout shown via CalloutPopupService.Show(...) and I ran into an issue with arrow positioning when screen space is limited.

Scenario

The RadCallout is displayed relative to a FrameworkElement (placementTarget), in normal cases, everything works as expected, however, when the application window is close to the right screen edge, or on a multi-monitor setup, the following happens:

The popup is automatically repositioned to the next screen if there is one and doesn't stay on the screen where the wpf app is shown or if there is no aditional screen the RadCallout no longer aligns horizontally with the placementTarget.

The arrow still uses its original relative position → and no longer points to the target element

I already handle vertical cases manually:

• If there is not enough space above → I switch the arrow to the bottom
• This works fine

But for horizontal constraints (left/right edges):

• The popup doesn't stay within screen bounds
• The arrow does not adjust automatically to still point at the placementTarget

Any Ideas how I could fix it?

[Martin Ivanov]

Hello Alina,

To achieve your requirement, you can manually calculate the position of the popup using the CalloutPopupSettings. I've attached a sample project showing this idea. I hope it helps.

In addition, I've logged a new feature request to add an option to disable the default Popup monitor re-position behavior, and also updated your Telerik points. 

Regards,
Martin Ivanov
Progress Telerik

[Alina]

Hello Martin,

thanks a lot for your help.

Best regards,

Alina