Declined
Last Updated: 03 Jun 2024 13:31 by Petar
SelectedItems collection not updated when items are removed
Declined
Last Updated: 28 May 2024 08:17 by ADMIN

We use a RadTreeView with many different item types that set a DefaultImageSrc based on a combination of item type and state
(from each item's view model).

For the currently selected TreeView item we would like to modify the item's image with a coloured border.
So it would be a very useful feature, if the TreeView item's SelectedImage could be derived from the DefaultImageSrc
via XAML Shapes (Rectangle, Line, etc.).
(Shapes can e.g. already be used to draw TreeView's Expander-Button for expanded/collapsed state, which is very useful).

Currently the only approach is to copy any item-type's image in the file system and modify it for selected state.
(Thus doubling the number of item image files.)
Given the number of images for different item types and states that we already have, this is not very practical.

Examples for DefaultImageSrc (left) and SelectedImageSrc (right):

  •  -> 
  •  -> 

Is it possible to extend RadTreeView, so that the SelectedImageSrc can be based on the given DefaultImageSrc, but with a modification provided via XAML?


Declined
Last Updated: 17 May 2022 09:39 by ADMIN
Setting the color variation of the VisualStudio2019Palette to ColorVariation.Dark of the VisualStudio2019 theme makes the TreeViewItem elements difficult to read (gray foreground on a white background).
Declined
Last Updated: 05 Apr 2021 10:29 by ADMIN
Created by: Markus
Comments: 1
Category: TreeView
Type: Bug Report
1

Dear Telerik team,
We currently have a problem with the RadDragAndDropManager as we are currently in the process of converting from Silverlight to WPF.
We are also converting Telerik from version 2011.2 to the current version of Telerik WPF.
Now the following error happens:
If I drag an item and drag it over another dropable area, the DragCue element moves.
The error occurs as soon as "e.QueryResult" is set to true in the OnDropQuery function.
You just have to do that, otherwise the drop will not be evaluated.

I was able to recreate the whole thing in a new project with just a RadTreeView and a RadMap.
I just don't want to switch the RadDragAndDropManager to the DragDropManager because we have a lot of our own controls that run with the old one, but not with the new one.
I've already tried that, but the conversion effort is just too big.
Can you see why the DragCue element is acting so weird?

With best regards

Markus Kuhlemann

Declined
Last Updated: 17 Jan 2020 09:16 by ADMIN

When a large number of items are selected through extended selection (with a lot of items on the first level of the RadTreeView) the selection does not work correctly. 

Workaround - make the selection in viewmodels manually and provide 2way bindings in style
 <telerik:RadTreeView.ItemContainerStyle>
                <Style TargetType="telerik:RadTreeViewItem">
                    <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
                    <Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
                </Style>
            </telerik:RadTreeView.ItemContainerStyle>
private void SomeRadTreeView_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            int count = e.AddedItems.Count;
            if (count > 1)
            {
                SomeViewModel first = e.AddedItems[0] as SomeViewModel;
                SomeViewModel last = e.AddedItems[count - 1] as SomeViewModel;
                
                this.SomeRadTreeView.SelectionChanged -= this.SomeRadTreeView_SelectionChanged;
                this.SomeRadTreeView.AutoScrollToSelectedItem = false;
                this.ViewModel.SelectRange(first, last);
                this.SomeRadTreeView.AutoScrollToSelectedItem = true;
                this.SomeRadTreeView.SelectionChanged += this.SomeRadTreeView_SelectionChanged;
            }
        }

Declined
Last Updated: 19 Jan 2018 05:47 by wu
with RadTreeView control,using MVVM binding,the xaml like :
AutoScrollToSelectedItem="True"  IsVirtualizing="False"
looking the attach files,Navigate by the  RadBreadcrumb(the RadBreadcrumb and the RadTreeView binding the same data source,and binding the same SelectedIem),
when expand the level4,the RadTreeView  can't bring the selected item to view,but scroll mouse to the seleced item view,then Navigate again the same postion ,it can scroll,the radtreeview can reach the selected item.
     I test the microsoft treeview,if the Virtualizing is true,it can't scroll the selected item,but set the Virtualizing  to false,it is good.
    the other question,how to set the style?the  selected item's highligh area can expand the full row,like the visual studio.
Declined
Last Updated: 21 Dec 2017 12:46 by ADMIN
a) Using WCF RIA Services
b) Using QueryableDomainServiceCollectionView
c) Using TreeView with above two
d) Including LoadOnDemand
e) Using "Prepared Item"
Declined
Last Updated: 09 Jan 2017 15:54 by ADMIN
Created by: Ivar
Comments: 2
Category: TreeView
Type: Bug Report
0
When sorting a table I get the following stacktrace.

06.12.2016 15:39:34 Error General Object reference not set to an instance of an object.
System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Windows.Controls.ItemContainerGenerator.Remove(GeneratorPosition position, Int32 count, Boolean isRecycling)
   at Telerik.Windows.Controls.TreeView.TreeViewPanel.CleanupRange(IList children, IItemContainerGenerator generator, Int32 startIndex, Int32 count)
   at Telerik.Windows.Controls.TreeView.TreeViewPanel.CleanupContainers(Int32 firstViewport, ItemsControl itemsControl)
   at Telerik.Windows.Controls.TreeView.TreeViewPanel.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   at System.Windows.Controls.Grid.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Controls.Control.MeasureOverride(Size constraint)
   at Telerik.Windows.Controls.RadTreeViewItem.MeasureOverride(Size availableSize)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at Telerik.Windows.Controls.TreeView.TreeViewPanel.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
...
Declined
Last Updated: 04 Jan 2017 12:57 by ADMIN
ADMIN
Created by: Pavel R. Pavlov
Comments: 0
Category: TreeView
Type: Feature Request
0
Change the selection on MouseLeftButtonUp instead of MouseLeftButtonDown.

DECLINED: Duplicate with https://feedback.telerik.com/Project/143/Feedback/Details/112812-treeview-perform-selection-on-mouseleftbuttonup
Declined
Last Updated: 29 Dec 2016 14:20 by BHAGWATI
We have a RadTreeView. There is no horizontal scrollbar.
We edit a node's header to a longer string and a horizontal scrollbar appears.
If we edit again the node's header to a shorter string, the horizontal scrollbar remains even it isn't needed anymore.

UPDATE:
There is a similar problem with the height of a RadTreeViewItem.
If we edit the RadTreeViewItem's content to become at least of two lines - the height of the item is increased, which is expected.
But if we re-edit this item's content to be on one line only - the height of the item remains larger, which is incorrect.
Please note, that this issue is observed ONLY on sub-items not on the parent nodes.

This seems not reproducible  with R3 2016 version of RadTreeView.
Please open a new support ticket with details regarding this issue if you encounter it.
Declined
Last Updated: 07 Dec 2016 15:12 by ADMIN
When the FlowDirection is RightToLeft, the vertical lines of the control aren't properly aligned.

The issue is not reproducible with R3 2016 Release.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
When value types are inserted in the Items collection of RadTreeView and root values are duplicated in the children a StackOverflowException is raised after a call to ExpandAll.

The XAML has recently reviewed the status of this issue and won't be addressing it in future releases.
This is a design limitation - RadTreeView does not support duplication of value types in its Items / ItemsSource collections. 
This potentially can cause troubles with virtualization / selection / expandALL features.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
Setting the IsChecked via binding causes synchronization issue with CheckState during initial container creation.

Declined.

IsChecked and CheckState are not supported in binding scenarios. In databinding scenarios use the approach described here.
http://www.telerik.com/help/wpf/radtreeview-howto-tri-state-mvvm.html
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
The TreeViewPanel doesn't display the TreeViewItems when the TreeView ItemsPresenter ControlTemplate element is wrapped in a Border or Grid control.

Declined.

Changing the default control template of our controls is risky, every template part has its purpose and usually it is used in code behind. 
We cannot support such template changes to not reflect the main features such as virtualization,scrolling, fast performance.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
Ability to have both static and bound RadTreeViewItems or different hierarchy levels.

Reason for decline: There is no proper way this to be implemented.
 This would require huge refactoring of the DragDrop, Styling, Editing, Virtualization logic. 
Complexity of such task  is close to writing a new control from scratch.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
DataTriggers that apply DefaultImageSrc, ExpandedImageSrc don't work when the TreeView is virtualized.
Reason for deletion:
The workaround is easy - just bind the DefaultImageSrc, ExpandedImageSrc to string properties from the ViewModel.
Also, a possible fix would slow down the virtualization process in the RadTreeView.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
Improve the synchronization between the TreeView.IsOptionElementsEnabled with the TreeViewItem.OptionType property. In a scenario where the TreeViewItem.OptionType property is databound, changing the TreeView.IsOptionElementsEnabled property doesn't respect the databound values of the TreeViewItem.OptionType.
===
Reason for deletion: These  proeprties are marked obsolete.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
ADMIN
Created by: Telerik Admin
Comments: 1
Category: TreeView
Type: Bug Report
13
When TreeView is placed inside floating VS ToolWindow and item is selected the visual state remains unchanged after focus leaves the TreeView.
Declined
Last Updated: 11 Aug 2016 14:04 by David Liebeherr - rent-a-developer
When the RadTreeView is virtualizaed, the images are  not shown. This works when the tree is bound to collection of objects and the DefaultImageSource is bound.

Reason for deletion:
The workaround is easy - just bind the DefaultImageSrc, ExpandedImageSrc to string properties from the ViewModel.
Also, a possible fix would slow down the virtualization process in the RadTreeView.
Declined
Last Updated: 11 Aug 2016 14:04 by ADMIN
Items are lost after reexpanding when TreeView is Virutalized and items are set in XAML.
Currently the TreeView does not support virtualization when using XAML items.

Reason for Decline: Virtualization is not supported in non-databound treeviews.
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