Telerik Forums
UI for WPF Forum
0 answers
26 views

Hello Telerik Team,

I am currently working with TreeListView in a WPF application and I am facing an issue related to row background color overriding when a row is selected.

In my application, certain rows need to have a custom background color depending on their type (for example: LocalFile and RemoteFile). The custom color works correctly when the row is not selected.

However, when the row is selected, the default RadTreeListView selection background color overrides the custom color, and the File-specific color is no longer visible.

My goal is to preserve the custom background color when the row is selected.

Below is a simplified version of the style currently used:

<Grid.Resources>
 
    <​Style TargetType="telerik:TreeListViewRow">
 
        <!-- Default row color based on data -->
        <Setter Property="Background">
            <Setter.Value>
                <Binding Path="FileSource">
                    <Binding.Converter>
                        <converter:SourceTypeToColorConverter/>
                    </Binding.Converter>
                </Binding>
            </Setter.Value>
        </Setter>
 
        <Setter Property="MouseOverBackground" Value="LightBlue"/>
 
        <​Style.Triggers>
 
            <!-- Default selected row color -->
            <Trigger Property="IsSelected" Value="True">
                <Setter Property="Background" Value="LightBlue"/>
            </Trigger>
 
            <!-- Selected color for local files -->
            <MultiDataTrigger>
                <MultiDataTrigger.Conditions>
                    <Condition Property="IsSelected" Value="True"/>
                    <Condition Binding="{Binding FileSource}" Value="LocalFile"/>
                </MultiDataTrigger.Conditions>
                <Setter Property="Background" Value="LightGreen"/>
            </MultiDataTrigger>
 
            <!-- Selected color for remote files -->
            <MultiDataTrigger>
                <MultiDataTrigger.Conditions>
                    <Condition Property="IsSelected" Value="True"/>
                    <Condition Binding="{Binding FileSource}" Value="RemoteFile"/>
                </MultiDataTrigger.Conditions>
                <Setter Property="Background" Value="LightYellow"/>
            </MultiDataTrigger>
 
        <​/Style.Triggers>
 
    <​/Style>
 
</Grid.Resources>

The issue occurs when the row becomes selected. The control applies the default selection background, which overrides these custom styles.
Could you please advise on the recommended way to maintain custom row background colors for specific items even when they are selected in TreeListView?
Any guidance or best practice would be greatly appreciated.
Thank you.

Rajdeep
Top achievements
Rank 1
 asked on 12 Mar 2026
1 answer
42 views

In a RadLayoutControl I use LayoutControlTabGroup.
I can set the background of the Item's but not on the "empty" space, is there some way to do that.

  <telerik:RadLayoutControl >
      <telerik:LayoutControlTabGroup Background="White">
          <telerik:LayoutControlTabGroupItem Header="Tab 1" Background="Red">
              <Button Content="Item 1" />
          </telerik:LayoutControlTabGroupItem>
          <telerik:LayoutControlTabGroupItem Header="Tab 2"  Background="Blue">
              <Button Content="Item 2" />
          </telerik:LayoutControlTabGroupItem>
      </telerik:LayoutControlTabGroup>
  </telerik:RadLayoutControl>

 

Stenly
Telerik team
 answered on 04 Mar 2026
0 answers
33 views
I have a RadGridView and I have implemented IDataErrorInfo on the view model.    Unfortunately, when the user types in something invalid and an error appears, the message is cut off.  I want to style it -- style... something -- so that the full error message will show.  But I don't know what property to set or what to style

Joe
Top achievements
Rank 1
 asked on 03 Mar 2026
1 answer
92 views


This is how my RadStepProgressBar appears for some of the steps.

When I change the Height (or StepSpacing or Margin) of the RadStepProgressBar control in XAML hot reload, the appearance corrects itself.



This doesn't always happen, but only sometimes. I have set the binding for the ItemsSource property of RadStepProgressBar to my steps collection, and set the SelectedIndex using binding whenever a step is completed

What am I doing wrong?
Ludwig
Top achievements
Rank 1
Iron
 answered on 27 Feb 2026
1 answer
24 views
Hi,
I open a RadOpenFileDialog  setting FileName with the full path of an existing file.
In the edit box in the low part of dialog I can see the path, and, if I click ok I get the file selected.
But in the list of files the path is not selected (the folder is also correctly set).

How can I select correctly the file and automatic scroll the view in order to see the seelction

Thank you
Luigi
Stenly
Telerik team
 answered on 19 Feb 2026
8 answers
455 views
Create a new WPF project, add a RadDocking to the page, then add a DocumentHost to the RadDocking, like so:

<telerik:RadDocking HasDocumentHost="True">
    <telerik:RadDocking.DocumentHost>
        <telerik:RadSplitContainer>
            <telerik:RadPaneGroup>
                <telerik:RadDocumentPane Header="Document 1" Title="Document 1" />
            </telerik:RadPaneGroup>
        </telerik:RadSplitContainer>
    </telerik:RadDocking.DocumentHost>
</telerik:RadDocking>

Run the app in debug mode and you'll get the following error in the VIsual Studio output window:

System.Windows.Data Error: 4 : Cannot find source for binding with reference 'ElementName=DropDownButtonElement'. BindingExpression:Path=IsChecked; DataItem=null; target element is 'DropDownMenu' (Name='DropDownMenuElement'); target property is 'IsOpen' (type 'Boolean')

Using version 2011.1.419.40. Noticed that there was a similar problem with the RadTabControl (see http://www.telerik.com/community/forums/wpf/tabcontrol/strange-error-message-in-debug-view.aspx). Can't reproduct the same error with RadTabControl. Suspect this is a similar issue. Doesn't cause any problems but would be nice to remove the error.

Can can anyone else confirm this?
Zalan
Top achievements
Rank 1
Iron
 answered on 18 Feb 2026
0 answers
35 views

Hi Team,

We are encountering an intermittent IndexOutOfRangeException when calling XamlFormatProvider.Export() on a RadDocument.

Exception stack:

System.IndexOutOfRangeException at System.Collections.Generic.Dictionary`2.Insert at Telerik.Windows.Documents.FormatProviders.Xaml.XamlWriter.TryGetTypeConverter at Telerik.Windows.Documents.FormatProviders.Xaml.XamlFormatProvider.Export(RadDocument)

Code:

private string ReadDocumentText(RadDocument document) { if (document == null) return string.Empty; return new XamlFormatProvider().Export(document); }

Notes:

  • document is not null

  • Each document is different

  • Same code works for most documents

  • The exception occurs inside Telerik export logic

  • Documents are exported concurrently (parallel processing)

  • No custom type converters or custom styles added explicitly

Questions:

  • Is XamlFormatProvider.Export() thread-safe when used concurrently?

  • Can concurrent exports cause internal state corruption (e.g. type converter dictionary)?

  • Is there a recommended approach for exporting RadDocument in parallel (e.g. synchronization or per-thread isolation)?

Any guidance would be appreciated.

Thanks.
Zafeer

Zafeer
Top achievements
Rank 1
 asked on 10 Feb 2026
0 answers
31 views

Hi ,

We have integrated RadRichTextBox into our WPF (C#) application and are trying to add RadCallout as a custom context menu. since the control is being created entirely in code-behind without XAML ,we are encountering implementation challenges.

Our expectation is that when a user selects text and right-clicks to choose the RadCallout option, the selected text should appear inside the callout type.

Could you please guide us on how to achieve this?

John
Top achievements
Rank 1
Iron
Iron
Iron
 asked on 05 Feb 2026
1 answer
83 views

Hello,

I have attempted to implement the solutions listed here.

We are using various ColorVariations along with our themes, however. For example:

StyleManager.ApplicationTheme = new Windows11Theme(Windows11Palette.ColorVariation.Dark);

The solutions listed in the link above throw the following exception:

System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it.

Is there a way to use theme ColorVariations along with RadSplashScreen?

Thank you

Nadya | Tech Support Engineer
Telerik team
 answered on 02 Feb 2026
0 answers
24 views

We have an app that has RadComboBox controls arranged above some RadNumericUpDown controls. For the RadNumericUpDown controls we have it set up to open a numeric pad on PreviewMouseUp to support both mouse and touch. The issue we have is that when a combobox item is selected that lies over a numericupdown using touch, the numericupdown control receives the focus and activates the numeric pad. This does not occur when using a mouse.

Attached is an example derived from our app that reproduces this behavior. Selecting Pounds or Newtons from the Force combobox using touch will cause a message box to appear.

Is there any way to work around this behavior? It is annoying but not a show-stopper.

Thanks,
Jim

Jim
Top achievements
Rank 1
 asked on 28 Jan 2026
Narrow your results
Selected tags
Tags
GridView
General Discussions
Chart
RichTextBox
Docking
ScheduleView
ChartView
TreeView
Diagram
Map
ComboBox
TreeListView
Window
RibbonView and RibbonWindow
PropertyGrid
DragAndDrop
TabControl
TileView
Carousel
DataForm
PDFViewer
MaskedInput (Numeric, DateTime, Text, Currency)
AutoCompleteBox
DatePicker
Buttons
ListBox
GanttView
PivotGrid
Spreadsheet
Gauges
NumericUpDown
PanelBar
DateTimePicker
DataFilter
Menu
ContextMenu
TimeLine
Calendar
Installer and Visual Studio Extensions
ImageEditor
BusyIndicator
Expander
Slider
TileList
DataPager
PersistenceFramework
Styling
TimeBar
OutlookBar
TransitionControl
FileDialogs
Book
ToolBar
ColorPicker
TimePicker
MultiColumnComboBox
SyntaxEditor
VirtualGrid
Wizard
ExpressionEditor
NavigationView (Hamburger Menu)
WatermarkTextBox
DesktopAlert
BarCode
SpellChecker
DataServiceDataSource
EntityFrameworkDataSource
RadialMenu
ChartView3D
Data Virtualization
BreadCrumb
LayoutControl
ProgressBar
Sparkline
TabbedWindow
ToolTip
CloudUpload
ColorEditor
TreeMap and PivotMap
EntityFrameworkCoreDataSource (.Net Core)
HeatMap
Chat (Conversational UI)
VirtualizingWrapPanel
Calculator
NotifyIcon
TaskBoard
TimeSpanPicker
BulletGraph
Licensing
WebCam
CardView
DataBar
FilePathPicker
PasswordBox
SplashScreen
Callout
Rating
Accessibility
CollectionNavigator
Localization
AutoSuggestBox
Security
VirtualKeyboard
HighlightTextBlock
TouchManager
StepProgressBar
Badge
OfficeNavigationBar
ExpressionParser
CircularProgressBar
SvgImage
PipsPager
SlideView
AI Coding Assistant
+? more
Top users last month
Boardy
Top achievements
Rank 2
Veteran
Iron
Benjamin
Top achievements
Rank 3
Bronze
Iron
Veteran
ivory
Top achievements
Rank 1
Iron
Iron
Rob
Top achievements
Rank 3
Bronze
Bronze
Iron
ClausDC
Top achievements
Rank 2
Iron
Iron
Iron
Want to show your ninja superpower to fellow developers?
Top users last month
Boardy
Top achievements
Rank 2
Veteran
Iron
Benjamin
Top achievements
Rank 3
Bronze
Iron
Veteran
ivory
Top achievements
Rank 1
Iron
Iron
Rob
Top achievements
Rank 3
Bronze
Bronze
Iron
ClausDC
Top achievements
Rank 2
Iron
Iron
Iron
Want to show your ninja superpower to fellow developers?
Want to show your ninja superpower to fellow developers?