IsStickyHeaderEnabled Repeating first header

[Jose]

I added the jumplist and everything works fine, except when I set IsStickyHeaderEnabled="true"
The first group header is always shown 2 times.

Any ideas how to work around this problem?

Jose

[Deyan]

Hi Jose,

Thanks for writing.

We are currently not aware of similar issue in RadJumpList. Could you please prepare a small Windows Phone 7 app that we can use to reproduce it and see what goes wrong.

Thanks for your time.

Regards,
Deyan
the Telerik team

[Jose]

Sorry for my super-delay answer, I was working in a different project.

The problem I see in my side is when you scroll up to the top of the jump list...If you keep "scrolling" the first header is show twice.

Can you please verify,

Jose

[Deyan]

Hello Jose,

Generally, the Sticky Header is a separate header element that is shown ontop of the viewport. If you apply a compression to the scrollable items by pulling them down when you have reached the top end of the scrollable list you will be able to see both the normal and the sticky header which will be the same - this is the expected behavior.

Anyway, we still are willing to investigate the case and therefore if you manage to send us a demo project that reproduces the undersired behvaior - we will be able to directly take a look at it.

Note that you will have to open a new support ticket in order to be able to attach your project.

Thanks for your time.

Greetings,
Deyan
the Telerik team

[Jose]

I hate to disagree with you. I don't think the behavior is expected or desirable. What's the point of repeating the first header on the list?.

If you open the Zune, then, select Music and go to Albums, if you scroll up and down the sticky header NEVER repeat. The WP7 applications list (right from the home screen) also the sticky header works perfect.

I you want to check a code sample you can use The Telerik Examples App, currently in the Marketplace, has the same problem. Just go to the JumpList/StickyHeader.

I hope this help.

Jose

[Deyan]

Hi Jose,

Thanks for writing back.

Indeed, you are right. I have checked the behavior both in Zune and also in the Phonebook app of WP7 and when the user reaches the top end of the scrollable list, the sticky header is hidden. We will try to improve the behavior of our control in this scenario.

I would also like to make some notes here. As we are using the ScrollViewer's System manipulation mode (the optimization Microsoft introduced in WP7.5 to improve scrolling performance) we do not have a direct control to the animation used when scrolling items. This animation is both started and performed off-thread and the properties (like VerticalOffset etc.) on the UI-thread are not updated regularly. This prevents us from tracking animations in a pixel perfect manner and thus update the sticky header exactly when the first item header appears on the screen.

We will anyway do our best to improve the behavior of RadJumpList here.

Thanks for your feedback.

Best wishes,
Deyan
the Telerik team