Good day!
I have a problem with determination of selected items when IsVirtualizing="True". In attached project I used two different ways to counting selected items: 1. With binding IsSelected property, 2. Just counting of treeview SelectedItems. And both are incorrect in situation when selecting some number of treeview items by clicking with Shift button (SelectionMode="Extended"). For example, I select more than 8000 items but received next: items with IsSelected = true property: 37, selected tree view items: 980
Link to download project sample: click
4 Answers, 1 is accepted
Hello Eugeny,
Thank you for the provided project.
I was able to reproduce the described behavior and I have logged the following item in our feedback portal for it: TreeView: Extended selection does not work correctly with the UI Virtualization enabled when there is a large number of items selected on the first level. You can follow the item in order to get notified for any developments. I have also updated your telerik points as a thank you for bringing this to our attention.
I am afraid that for the moment I cannot suggest a workaround for this issue, since it is related to internal functionality of the control. What I can suggest as an alternative is checking out our RadTreeListView component. We also have an article that demonstrates how to visually alter the RadTreeListView to make it similar to the RadTreeView: Customize RadTreeListView to look like a RadTreeView.
Regards,
Vladimir Stoyanov
Progress Telerik
Rank 1
Hello Vladimir!
Thank You for reply, but it is not possible to use RadTreeListView in my current work project because it has extremely low perfomance when using CellTemplateSelector with complex column template that has dozens of converters. Also RadTreeListView has memory leaks while scrolling that i can't explain, in RadTreeView i don't see it
Hello Eugeny,
You can check out the Tips and Tricks article of the RadGridView (it is also valid for the RadTreeListView) in order to learn the recommendations for improving the performance of the control. Indeed using complex CellTemplates along with converters is not recommended.
That said, with regards to the mentioned memory leaks, may I ask you to share a sample project demonstrating that? You can do so by opening a new support ticket (since projects cannot be attached to forum posts). This will hopefully allow us to investigate the scenario and better assist you.
Regards,
Vladimir Stoyanov
Progress Telerik