Last Updated: 27 Feb 2020 12:49 by ADMIN
Release LIB 2020.1.302
Created by: Olivier
Comments: 1
Category: SyntaxEditor
Type: Bug Report


When we resize the syntaxEditor control, the folding buttons moved. You can reproduce this isssue in your demos.


  1. Reduce the contents of the sample
  2. Increase the size of sample window and see the buttons are not besides the line


Best regards,

Last Updated: 17 Feb 2020 13:43 by ADMIN
Foldings are incorrect when there is a missing open or close tag.
Last Updated: 14 May 2020 15:18 by ADMIN
Release LIB 2020.2.518 (18.05.2020)

When the control is inside ScrollViewer and you click it, focus is lost and caret disappears. Some controls have built in ScrollViewer , for example LayoutControl so placing the editor in LayoutControl also leads to the same issue.

Generally placing the syntaxeditor in scrollviewer is risky for the vertical virtualization so at least a height should be set to the control. In R2 2020 SP, an exception will be thrown if Syntax Editor with no height is added in scroll viewer or stack panel or other panel which measures vertically with infinity.

Workaround for this issue:

        private void syntaxEditor_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
            e.Handled = true;
Last Updated: 10 Apr 2020 05:08 by ADMIN
Release LIB 2020.1.413 (04/13/2020)
If secondary wpf window is opened in an application, the enter key does not work in SyntaxEditor. It does not produce new line as expected.
Last Updated: 27 Sep 2019 08:24 by ADMIN
For example "//====" will not be commented in C#. 
Or "!====" wont' be commented in custom language if "!" is the commenting symbol.
The issue resides in the word splitting function in WordTaggerBase class.

Last Updated: 25 Nov 2019 15:04 by ADMIN
Release LIB 2019.3.1202

If you have an XML attribute with a string value, but the value is not fully rendered into the viewport, its color defaults to black, instead of the expected blue color.

To work this around, you can create a custom XmlTagger and override its GetTags() method. This will allow you to properly catch the string value and return it as a tag span element with its ClassificationType set to "string".

Last Updated: 22 Jan 2020 12:34 by ADMIN
Release LIB 2020.1.127 (01/27/2020)
'Cannot find resource named 'DragVisualStyle' error occurs in in the error list when using implicit styles.
Last Updated: 05 Feb 2020 15:06 by ADMIN
In some cases the string values in the XML attributes are not colored with the expected color, but default to black.
This was reproduced when there is only single quotation mark on visible on the line. And also if the count of the visible quotation marks on the line is an odd number (not always reproducible). 

Last Updated: 17 Oct 2019 08:29 by ADMIN
Release R3 2019 SP1
Folding tagger does not work for other languages than C#.
It should be renamed to CSharpFoldingTagger.
FoldingTagger should be base , extensible class with options to set collections of opening symbols (brackets) or words (for startinga  method / class, region) and closing symbols / words.

Last Updated: 20 Apr 2020 10:11 by ADMIN
Release LIB 2020.1.420 (04/20/2020)

SyntaxEditor showing XML/Html/XAML File and XMlFoldingTagger is registered.

Deleting the last bracket symbol ">" results in exception in XMLFoldingTagger.cs

Last Updated: 29 Apr 2020 09:21 by ADMIN
Release 2020.1.427

SyntaxEditor is in RadListBoxItem.

Entering space key does not produce text change and gets the focus lost our of the editor.


    private void RadSyntaxEditor_PreviewKeyDown(object sender, KeyEventArgs e)
            if (e.Key == Key.Space)
                (sender as RadSyntaxEditor).Insert(" ");
                e.Handled = true;
Last Updated: 22 May 2020 12:42 by ADMIN

For example:

some text // some comment

some text 2 // some comment 2

Specified argument was out of the range of valid values.
Parameter name: span



at Telerik.Windows.SyntaxEditor.Core.Text.DataStructures.ConcatenationRopeNode.GetText(Span span) in C:\WPF_Scrum\Current\Controls\SyntaxEditor\SyntaxEditor.Core\Text\DataStructures\ConcatenationRopeNode.cs:line 140
   at Telerik.Windows.SyntaxEditor.Core.Text.TextSnapshot.GetText(Span span) in C:\WPF_Scrum\Current\Controls\SyntaxEditor\SyntaxEditor.Core\Text\TextSnapshot.cs:line 118
   at Telerik.Windows.Controls.SyntaxEditor.Taggers.CSharpFoldingTagger.GetFoldingRegionTitle(String inputValue, Span span, String startText) in C:\WPF_Scrum\Current\Controls\SyntaxEditor\SyntaxEditor\Taggers\Folding\CSharpFoldingTagger.cs:line 202

Last Updated: 18 May 2020 12:08 by ADMIN
Release LIB 2020.2.518 (05/18/2020)
Keyboard focus is lost on CompletionListWindow when setting runtime new collection to the CompletionListItems property. The values inside CompletionListWindow can't be selected through the keyboard arrow keys.