Last Updated: 12 Nov 2019 13:45 by Petar

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
                <Style TargetType="telerik:RadTreeViewItem">
                    <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
                    <Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
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;

Last Updated: 31 Oct 2019 14:09 by ADMIN
In some themes the arrow points up and in other themes the arrow points down. We should make sure that this behavior is consistent across themes. 
Last Updated: 04 Nov 2019 11:28 by ADMIN
Last Updated: 04 Nov 2019 13:50 by ADMIN

RadComboBox dropdown list leave a blank after the last item!

look the attachment.

Last Updated: 04 Nov 2019 12:59 by ADMIN
Created by: wu
Comments: 2
Category: UI for WPF
Type: Bug Report

    For the Pivot control,if the group header width greater than the first column width,when start the app,
the first column width will expand the group header width(like the attach file "Start.png"),
instead of it self width (like the attach file "ResizeColumn.png",it is our desired),moreover,when resize the column width,like the attach file "ResizeColumn.png",
then Collapse,the result like the attach file "Collapse.png",but not our desired the group header width(should not cover the text).

Last Updated: 14 Oct 2019 08:26 by ADMIN
Created by: Jason D
Comments: 2
Category: Map
Type: Bug Report

I have only seen this once. It's possible this is because I am using multiple maps at the same time. I think it crashed the application, but I do not recall.


  Message=The process cannot access the file 'C:\Users\jasond\AppData\Local\TelerikMapCache\Telerik.Windows.Controls.Map.BingRestRoadOnDemandSource.23x7935x11621' because it is being used by another process.
   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
   at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share)
   at Telerik.Windows.Controls.Map.FileSystemCache.OpenCacheStream(String fileName)
   at Telerik.Windows.Controls.Map.FileCacheBase.LoadAsync(String fileName, Action`1 callback)
   at Telerik.Windows.Controls.Map.TiledMapSource.GetCachedTileAsync(Int32 tileLevel, Int32 tilePositionX, Int32 tilePositionY, Action`1 callback)
   at Telerik.Windows.Controls.Map.MultiScaleTileSource.DownloadTile(TileId tileId)
   at Telerik.Windows.Controls.Map.TilesDownloadManager.RequestTile(Int32 requestLevel, Int32 tileX, Int32 tileY, Nullable`1 absTileX)
   at Telerik.Windows.Controls.Map.TilesDownloadManager.RequestTop3Levels(Int32 endLevel3)
   at Telerik.Windows.Controls.Map.TilesDownloadManager.Process()
   at Telerik.Windows.Controls.Map.TilesDownloadManager.DownloaderThread()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

Last Updated: 12 Sep 2019 15:58 by ADMIN
Created by: Matt
Comments: 1
Category: RichTextBox
Type: Bug Report

When importing from a .docx the RichTextBox is adding a blank line for each continuous section break. You can see this in the attached file - in the RichTextBox there is an extra line between sections that does not exist in the source word document.

Last Updated: 13 Sep 2019 15:54 by ADMIN

This can be reproduced with the provided .docx. In Word the image floats in the empty space below the text but the RichTextBox has it inline and overlapping text.

Removing the rectangle from around the image in the source document has no affect.

Last Updated: 14 Oct 2019 09:58 by ADMIN

Hi support,

We have a problem when we copy a text from MS word to RitchTextBox.
If the text copied uses an style that the namecontains tilde, then style name on the ritchtextbox is broken with strange characters.
All works well with this strange characters, but if you export to html and then import to ritchtextbox, the style is lost ...

This is a big problem because in spanish, many styles have tildes. When our user copy content from word they have problem with html format export / import.

I Attach a MS Word docx with a style with tildes:

Steps to reproduce it:

1- Open MS Word attached.
2- Copy the content.
3- Open a ritchTextBox Editor
4- Paste the content.
5- Export to html
6- Import the html.

You can see now, that the style are lost, and the name of the style contains strange characters.

Similar issue its happen when open a Word Docx with styles with tildes from ritchTextBox, not include strange characters but the style is lost.


Thanks for you support,

Last Updated: 28 Aug 2019 11:05 by ADMIN
Created by: Yaroslav
Comments: 1
Category: RichTextBox
Type: Bug Report

Hi Guys,

Our application works with a document storage and we use RadRichTextBox to allow users edit and view the documents. Unfortunately, many documents cannot be opened due to the following exception we get:

Unable to cast object of type 'Telerik.Windows.Documents.Model.FieldRangeStart' to type 'Telerik.Windows.Documents.Model.AnnotationRangeEnd

As result we receive complains from our users. Could you please facilitate with solving it? 

I have attached a simple test application with the problematic document as well the stacktrace. 

Best regards,


Last Updated: 10 Jul 2019 07:16 by ADMIN

The RadWindow's size shrinks while dragging it on a monitor with high DPI scale which causes it to shake a bit. In other words, the dragging is not smooth.

This was reproduced on a monitor with DPI scale set to 175%.
This is reproducible if you set the RadWindowInteropHelper.AllowTransparency on the RadWindow control (regardless of the value - True or False).
This is more noticeable in .NetCore projects.

Last Updated: 09 Jul 2019 13:06 by ADMIN

See attached picture together with these steps.

  1. select a item in the list
  2. import multiple other items in one go -> the last imported item is marked as selected (this is OK), the previously selected item is no longer marked as selected (this is OK).
  3. SHIFT select the first item of the ones imported in step 2 -> the items between the last imported item and the first imported item are selected, but the item that was selected in step 1 is now also selected...


Thanks in advance!



Last Updated: 09 Jul 2019 06:32 by ADMIN
when open the RadRibbonBackstage by click the ApplicationButton ,if click some one area which is not  the above ApplicationButton,
then the RadRibbonBackstage  is closed,the ApplicationButton's fluent mouseover effect don't disappear
check the Additional file .
Last Updated: 28 Jun 2019 14:11 by ADMIN

Hi Telerik,

We are converting XAML content into PDF file with below code.

private byte[] Xaml2Pdf(string xamlContent)
		XamlFormatProvider xamlFormatProvider = new XamlFormatProvider();
		PdfFormatProvider pdfFormatProvider = new PdfFormatProvider();
		PdfExportSettings exportSettings = new PdfExportSettings();
		exportSettings.ContentsCompressionMode = PdfContentsCompressionMode.Automatic;
		exportSettings.ContentsDeflaterCompressionLevel = 9;
		exportSettings.DocumentInfo = new PdfDocumentInfo() { Producer = "ALIS", Author = "ALIS", Creator = "ALIS" };
		exportSettings.ImagesCompressionMode = PdfImagesCompressionMode.Automatic;
		exportSettings.ImagesDeflaterCompressionLevel = 9;
		pdfFormatProvider.ExportSettings = exportSettings;

		byte[] content = pdfFormatProvider.Export(xamlFormatProvider.Import(xamlContent));

		return content;
When we convert attached XAML content with above code it will gives an output pdf file but when we open pdf file into Adobe Reader DC it will display some error message before opening it.

Currently we are using 2016.2.905.45 version.

Previously when we was use 2016.1.302.45 version at that time we didn't notice same issue.

Please assist.

Thank you.
Last Updated: 20 Jun 2019 08:24 by ADMIN

Adding bookmarks with the same name programmatically always returns the first one in case use attempts to navigate to it using the Bookmarks dialog. 

Workaround: Remove the bookmark before adding a new one with the very same name.

Last Updated: 27 Jun 2019 10:32 by ADMIN
When the FixedDocumentSinglePagePresenter content control is used to visualize PDF files in custom PDF viewer implementation a raise condition can be occurred leading to NullReferenceException with the following stack trace:
at Telerik.Windows.Documents.Fixed.UI.UIElementsHelper.FillPageContentElementsInPanel(Canvas container, RadFixedPage page)
at Telerik.Windows.Documents.UI.FixedDocumentSinglePagePresenter.CreateContent(RadFixedPage page)
at Telerik.Windows.Documents.UI.FixedDocumentSinglePagePresenter.PageLoader_WorkCompleted(Object sender, WorkCompletedEventArgs e)
at Telerik.Windows.Documents.Utilities.ResourceLoader.OnWorkCompleted(WorkCompletedEventArgs args)
at Telerik.Windows.Documents.Utilities.ResourceLoader.Worker_RunWorkerCompleted(Object sender, RunWorkerCompletedEventArgs e)
at System.ComponentModel.BackgroundWorker.OnRunWorkerCompleted(RunWorkerCompletedEventArgs e)
at System.ComponentModel.BackgroundWorker.AsyncOperationCompleted(Object arg)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

The exception is thrown since the current page is unloaded while the content is being parsed.
Last Updated: 21 May 2019 12:43 by ADMIN

Environment: VS Community 2019 (16.0.3), with .NET Framework 4.8 (release version, run-time and developer pack installed), Windows 10 Pro October 2018

Telerik UI version: latest (2019.1.220.45)


When VS2019 opened, Telerik UI for WPF should have been found under the "Extension" menu --> Telerik --> Telerik UI for WPF. However, there is only "Telerik UI for WinForms" under "Telerik" now. There is neither "Telerik scenario" in the "Add New Item" window so no RadForms can be created. Manually replacing <Window> in XAML to <telerik:RadWindow> does change the appearance of the window in the designer, but the properties in the Property window does not change accordingly to RadForms but still WPF standard Form ones. Toolboxes shows current lists of Telerik UI for WPF controls and they can be correctly created (at least RadButton). "Repair" in the Progress Control Panel doesn't fix this problem.



Last Updated: 15 May 2019 14:28 by ADMIN
Created by: Philipp
Comments: 1
Category: ComboBox
Type: Bug Report

The following xaml code

            <telerik:RadComboBox Margin="5"
                                 ItemsSource="{Binding Path=AvailableServices}"
                                 Text="{Binding Path=Service, Mode=TwoWay}"/>

            <ComboBox Margin="5"
                                 ItemsSource="{Binding Path=AvailableServices}"
                                 Text="{Binding Path=Service, Mode=TwoWay}"/>

with this view model

public class ViewModel

{ public ObservableCollection<string> AvailableServices { get; set; } = new ObservableCollection<string> { "UPS Standard", "UPS Express Saver", "UPS Express 12:00", "UPS Express" }; public string Service { get; set; } = "UPS Express"; }

produces the attached output. 


The standard WPF ComboBox is set to "UPS Express" as expected while the RadComboBox shows "UPS Express Saver" which probably was incorrectly autocompleted. 

Last Updated: 13 Aug 2019 13:18 by ADMIN
If you try to show a window, and right afterwards call RadWindow.Alert() or any other prompt dialog, the main window automatically closes.

To work this around show the prompt in the Loaded event handler of the RadWindow.
Last Updated: 26 Sep 2019 13:19 by ADMIN
You can observe the difference between the ChartView and an Excel Chart with the same data in the attached pictures.
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