Last Updated: 24 Oct 2023 15:19 by ADMIN
Created on: 18 Oct 2023 10:00
Category: UI for WPF
Type: Bug Report
ScheduleView virtualization rendering issues for group headers with different sizes


Since we want to boost up the performance of the ScheduleView , we've applied the 2023_2_718 UI for WPF to enable the virtualization of the group headers with setting the property  IsGroupHeadersVirtualizationEnabled="True". However we've experienced issues also with rendering for the appointments and group headers(resources) when scrolling.

In one of the screens where the schedule view is used, the group headers don't have equal sizes, for example:

The height may vary depending on the overlapping appointments for the resource which is allowed for our system. 

There is a note that there might be issues and unexpected behavior when the headers have different sizes claimed here:

WPF ScheduleView - UI Virtualization - Telerik UI for WPF

In this scenario we experience multiple issues, like for example when scrolled at the bottom, and the schedule view is fully refreshed, the resources and appointments are not rendered :

until it's scrolled.

Also when scrolling, we experience a "blinking" rendering, the group headers change sizes on scrolling :



Can you please let us know if/when this is planned to be fixed.


Another issue not related to the header size differences is that some of the appointments are lost (not rendered)  when the height of the schedule view is changed resulting in some of the appointments to not be visible anymore .The selection is kept on the group headers, but the appointments are not rendered.


Thank you!

1 comment
Petar Mladenov
Posted on: 24 Oct 2023 15:19

Hi Marko,

You have hit a limitation of the virtualization of the ScheduleView's resource group headers. In fact, you can rarely see a UI virtualization implementation which claims to support virtualization of containers of different sizes. He have no direct plans in changing the virtualization technique used. Instead, we would consider implementing a mechanism which limits the size of the headers somehow which might include special arrangement of appointment containers in limited space (such that increasing containers does not increase the resource headers). We have logged such feature request in our feedback portal already.

Regarding the other issue with the missing appointments, can you please confirm that turning off the headers virtualization does not solve the issue ? If yes, can you somehow isolate this scenario and send it to us for detailed investigation ? Thank you in advance.

Petar Mladenov
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