Won't Fix
Last Updated: 14 Nov 2023 15:58 by ADMIN

Reset by Clear, RemoveRange causes a memory leak of GridViewRow instances (or TreeListViewRow in RadTreeListView).

To work this around, you can call the Clear method of the RadGridView's Items collection and then reset the ItemsSource property.

this.radGridView.ItemsSource = null;
this.radGridView.ItemsSource = newSource;
Edit: The number of instances of the GridViewRow class are relative to the number of containers which cover the visible viewport. They are kep by internal caching mechanism used for faster reuse of containers is data-reload scenarios. Containers are dettached from their previous viewmodels (DataContext).

In non virtualized scenario, the number of the live containers is the same as the number of items in the GridView's ItemsSource and when changing the source, the number remains the same as the items in the source.

We are closing this issue as we think the mentioned internal cache shouldn't be considered a memory problem but rather a powerful performance optimization internal tool for extensive data-refresh scenarios.
Won't Fix
Last Updated: 24 Oct 2023 10:10 by Petar
Associated AutomationProperties.Name is read twice by JAWS.
Won't Fix
Last Updated: 14 Sep 2023 15:35 by ADMIN
Multiple operations applied on a big RadBitmap can cause OutOfMemoryException because of used and not disposed unmanaged resources in a WriteableBitmap object.

Steps to reproduce:
- Execute multiple times the Rotate tool
Observe: The memory goes up and retains such.
Expected: The unmanaged memory is cleared.

Findings: the memory leak is related to the WPF class WriteableBitmap which is internally used by the RadBitmap. Attached is a sample project illustrating the problem using only WPF classes.
Note: At this point, we are not aware of a possible fix.
Won't Fix
Last Updated: 08 Aug 2023 15:02 by ADMIN
When the collection bound to the AppointmentsSource property is cleared and filled with data again, the tooltip of one of the appointments could become visible and it will be displayed on top of all applications.
Won't Fix
Last Updated: 31 Jul 2023 13:51 by ADMIN
Highlighted text's color is set to gray when saving and reopening the file.
Won't Fix
Last Updated: 04 Jul 2023 09:36 by ADMIN

The ZIndex property change is not detected by the VisualizationLayer at runtime. 

Workaround: remove and then add back the item where the ZIndex is changed.

Won't Fix
Last Updated: 21 Apr 2023 13:54 by ADMIN
A binding error appears in the VS Output pane on startup of the RadOpenFileDialog. The error states the following:
System.Windows.Data Error: 26 : ItemTemplate and ItemTemplateSelector are ignored for items already of the ItemsControl's container type RadBreadcrumbBarItem
The error can be ignored because it doesn't break the file dialog functionalities.
Won't Fix
Last Updated: 19 Jan 2023 14:25 by ADMIN
The mouse-over highlight color is not applied to the correct row when the rows are navigated via the keyboard arrows.
Won't Fix
Last Updated: 30 Nov 2022 16:33 by ADMIN
Clicking on a RadDropDownButton in the Visual Studio 17.4.0 designer makes it stop responding.
Won't Fix
Last Updated: 06 Oct 2022 09:48 by ADMIN
Can be observed in FirstLook demo of the RadGridView.
While resizing the demos window, radgridview's horizontal scrollbar might flicker when demos viewport size is close to the gridview size.
Won't Fix
Last Updated: 06 Oct 2022 09:20 by ADMIN
Created by: Martin Ivanov
Comments: 1
Category: Docking
Type: Bug Report
A memory leak related to the automation peers of the RadPane and RadPaneGroup appears when you close a pane (using its Close button) even if you call its RemoveFromParent() method.

To work this around disable the automation peers. To do so please set the static AutomationManager.AutomationMode property toAutomationMode.Disabled.
public MainWindow()
    AutomationManager.AutomationMode = AutomationMode.Disabled;

The issue originates from ItemsControlAutomationPeer. It is reported to Microsoft in their old connect portal here =>

Won't Fix
Last Updated: 02 Jun 2022 15:14 by ADMIN
InvalidOperationException regarding QuickStyle Freezable is thrown when the control is opened in new STA thread.
Won't Fix
Last Updated: 03 May 2022 13:40 by ADMIN
DataContext of rows is sometimes null when UI virtualization is enabled in the Flat group render mode.

The issue appears also without UI virtualization and in the Nested mode. It happens on ItemsSource reset of RadGridView, in case the old ItemsSource value wasn't empty. The DataContext is set to null for a brief moment before the old visuals are removed from the view, which causes issues in some scenarios related to CellTemplate
Won't Fix
Last Updated: 04 Apr 2022 12:38 by ADMIN


I am currently having issues with RadGridView's group footer: I am trying to add a button to the footer template which is supposed to trigger a command which in turn needs some info on the group it was triggered from*.

Since (unlike the header) there does not seem to be any info on the group available directly within the GroupFooterTemplate, I am pulling the group info from the parent GridViewGroupFooterRow:

                <telerik:GridViewDataColumn [...]>
                            <Button Command="{Binding DataContext.ShowFooterGroupCommand, RelativeSource={RelativeSource AncestorType=telerik:RadGridView}}"
                                    CommandParameter="{Binding Group.Key, RelativeSource={RelativeSource AncestorType=telerik:GridViewGroupFooterRow}}" />

This is working great as long as the RadGridView does not use Row virtualization. However, when I turn on Row virtualization and scroll around for a bit, the value I get passed as the CommandParameter is more or less random and has nothing to do with the group my button is actually located in.

I attached a small example project (.Net 6 but our app uses 4.8 so I set that as the Framework below) for you to try it yourself. Just scroll around and click the buttons while watching the debug output window. You will see that the groups in the output window will not match the group where you actually clicked the button after some scrolling.

Expected Behavior

Even when virtualizing, the Group key returned when binding to GridViewGroupFooterRow.Group(.Key) should reliably return the key of the actual group my button is placed in. It would be even better if it was somehow possible to get the group directly, without having to resort to FindAncestor.

Simon Müller
Hofmann Fördertechnik GmbH


* Basically I am trying to give the user a possibility to add new items to the individual groups and I don't want to add the button to the group header since that makes it too easy to accidentally hit the header's RadToggleButton, collapsing the group.

Won't Fix
Last Updated: 20 Dec 2021 15:51 by Stenly
When clicking the remove button on an item, which is present more than once in the selection textbox, the first occurrence will be removed, rather than the corresponding item.
Won't Fix
Last Updated: 14 Jul 2021 14:22 by ADMIN
The designer of VS crashes with a "Key cannot be null" when custom markup extension is used in Style Setter. This reproduces in the sample app attached in the blog (http://www.telerik.com/blogs/bring-office-2016-inspired-style-to-your-app-with-ui-for-wpf) on the TextBlock of the RabRadioButton HeadingStyle (snapshot attached) if you open MainWindow in Designer. Runtime everything works as expected.
Won't Fix
Last Updated: 16 Jun 2021 14:03 by ADMIN
When the RadWindow is declared in XAML and is used as a main window, it won't show in the designer by simply merging the required theme resources and defining an implicit style based on the RadWindowStyle.

Tested with 16.8.4 - works as expected. Updated to 16.9.0 to match the client's setup and managed to reproduce the issue. The issue is reproducible also with the 16.10.0 version of Visual Studio.

Won't Fix
Last Updated: 10 Feb 2021 09:59 by ADMIN
The RadGridView's is bound to an empty DataView and grouped by a GridViewComboBoxColumn. When adding items during runtime, setting the SelectedItem in code or selecting through the UI -> the SelectedItem remains null. 
Won't Fix
Last Updated: 16 Sep 2020 11:25 by ADMIN

The check mark of the RadioButton is misaligned when DPI settings are set to a higher than the default value, e.g. 125%.

The problem can easily be reproduced using the Telerik UI for WPF Demo application:

1 2 3 4 5 6