Last Updated: 31 Jul 2020 11:29 by ADMIN
When the filtered items in the RadGridView do not contain the currently selected items, they are cleared. 
Last Updated: 21 May 2020 08:28 by ADMIN
Release LIB 2020.2.526 (05/26/2020)

If you select an item in RadMultiColumnComboBox and then replace the ItemsSource of the GridViewItemsSourceProvider, the selection in the autocompletebox part of the the control is not cleared. There are items that are still selected and are not presented in the ItemsSource.

To work this around, you can create a custom GridViewItemsSourceProvider and override its OnPropertyChanged method. When the ItemsSource is changed, you can reset the selection.

public class CustomGridViewItemsSourceProvider : GridViewItemsSourceProvider
	public RadMultiColumnComboBox Owner
		get { return (RadMultiColumnComboBox)GetValue(OwnerProperty); }
		set { SetValue(OwnerProperty, value); }
	public static readonly DependencyProperty OwnerProperty =
			new PropertyMetadata(null));

	protected override void OnPropertyChanged(DependencyPropertyChangedEventArgs e)
		if (e.Property.Name == "ItemsSource" && this.Owner != null)

                <local:CustomGridViewItemsSourceProvider Owner="{Binding ElementName=mccb}" />

Last Updated: 29 Jan 2020 15:02 by ADMIN
Release LIB 2020.1.203 (02/03/2020)

The Validation.ErrorTemplate attached property is not set. To workaround this, you can use the following resource.

<ControlTemplate x:Key="ValidationTooltipTemplate">
    <Grid SnapsToDevicePixels="True" VerticalAlignment="Top">
        <Border Background="Transparent" HorizontalAlignment="Right" VerticalAlignment="Top" Width="3" Height="3"/>
        <AdornedElementPlaceholder x:Name="Holder"/>
        <Border BorderBrush="{StaticResource ValidationTooltipOuterBorder}" BorderThickness="1" CornerRadius="{StaticResource ValidationTooltip_CornerRadius}"/>
        <Path Data="M2,1 L6,1 6,5 Z" Fill="{StaticResource ValidationInnerTick}" Width="7" Height="7" HorizontalAlignment="Right" VerticalAlignment="Top"/>
        <Path Data="M0,0 L2,0 7,5 7,7 Z" Fill="{StaticResource ValidationOuterTick}" Width="7" Height="7" HorizontalAlignment="Right" VerticalAlignment="Top"/>
            <ToolTip x:Name="PART_ToolTip"
                DataContext="{Binding RelativeSource={RelativeSource Mode=Self}, Path=PlacementTarget.DataContext}"
                Template="{StaticResource ErrorTooltipTemplate}"

<Style TargetType="telerik:RadMultiColumnComboBox" BasedOn="{StaticResource RadMultiColumnComboBoxStyle}">
    <Setter Property="Validation.ErrorTemplate" Value="{StaticResource ValidationTooltipTemplate}" />

Last Updated: 10 Feb 2020 16:26 by ADMIN
Release LIB 2020.1.210 (02/10/2020)

The following error is thrown when the dropdown of the control is opened: Cannot find governing FrameworkElement or FrameworkContentElement for target element. ... ; target element is 'GridViewItemsSourceProvider; target property is 'ItemsSource' (type 'Object')

If the combobox is placed inside a RadGridView, the error is thrown each time the dropdown is opened (after a commit action).

Last Updated: 15 Nov 2019 14:03 by ADMIN
Release LIB 2019.3.1118
A NullReferenceException is thrown after opening the dropdown and there is an implicit style targeting RadGridView which sets the SearchMode property.
Last Updated: 10 Apr 2020 05:07 by ADMIN
Release LIB 2020.1.413 (04/13/2020)
InvalidOperationException is thrown when programmatically adding items to the SelectedItems collection after the dropdown has been opened.
Last Updated: 18 Nov 2019 11:55 by ADMIN
Release LIB 2019.3.1118 (11/18/2019)
Dropdown does not close when OpenDropDownOnFocus is True and KeepDropDownOpen is False and the user has previously made a selection after opening the control by clicking on its textbox part.
Last Updated: 07 Nov 2019 11:02 by ADMIN
Created by: Mats
Comments: 3
Category: MultiColumnComboBox
Type: Bug Report

Hi Telerik-Team,


i found a bug similar to forum post, but not the same.

In MultiColumnComboBox when SelectionBoxesVisibility is set  to 'collapsed' and and whatever you set AutoCompleteMode to (different from the forum post),

if you select the first item it is not shown. Although the NullText is removed. It works perfectly for all the other items. This is quiet a problem if you only have one item in the dropwdown :D




Last Updated: 09 Dec 2019 11:43 by ADMIN
GridViewMultiColumnComboBoxColumn does not have any selected value in edit mode when SelectionBoxesVisibility is set to Collapsed/Hidden and AutoCompleteMode is Search/Suggest.
Last Updated: 02 Aug 2019 10:32 by ADMIN
Release LIB 2019.2.805 (8/05/2019)

If set the AutoCompleteMode property in a Style Setter, and exception is thrown.

To work this around set the property directly on the control.
<telerik:RadMultiColumnComboBox AutoCompleteMode="Search" />

Last Updated: 15 Feb 2019 14:25 by ADMIN
Created by: Alexander
Comments: 2
Category: MultiColumnComboBox
Type: Bug Report

Hello Telerik,

Exception is thrown after typing in the autocompletebox and selecting an item right after that. 

  Message=Exception has been thrown by the target of an invocation.
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Delegate.DynamicInvokeImpl(Object[] args)
   at System.Windows.RoutedEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
   at Telerik.Windows.Controls.GridView.GridViewDataControl.RaiseSelectionChangedEvent(SelectionChangeEventArgs args)
   at Telerik.Windows.Controls.DataControl.RaiseSelectionChangedEvent(ItemSelectionChange selectionChange)
   at Telerik.Windows.Controls.DataControl.Telerik.Windows.Data.Selection.ISelectorInternal.RaiseSelectionChangedEvent(ItemSelectionChange selectionChange)
   at Telerik.Windows.Data.Selection.ItemSelectionHandler.EndAllowedSelection(ItemSelectionChange selectionChange)
   at Telerik.Windows.Data.Selection.ItemSelectionHandler.EndPendingSelection(ItemSelectionChange pendingSelection)
   at Telerik.Windows.Data.Selection.ItemSelectionHandler.EndSelection()
   at Telerik.Windows.Data.Selection.ItemSelectionHandler.SelectedItems_CollectionChanged(Object sender, 

Thanks in advance.


Last Updated: 16 Feb 2019 10:24 by ADMIN
If you set the SelectionMode of the control to Multiple the SelectionChanged event fires only when you select item for the first item. Each next selection won't fire the event.

To work this around use to CollectionChanged event of the SelectedItems collection of RadMultiColumnComboBox.
Last Updated: 15 Feb 2019 09:08 by ADMIN

The event should fire when the DropDownContentManager gets initialized.

To work this around use the InitializeSelectionBridge event. The DropDownContentManager is initialized when this event fires.

Last Updated: 03 Jan 2019 11:52 by ADMIN
Created by: Tino
Comments: 2
Category: MultiColumnComboBox
Type: Bug Report



when selecting more items and dropdown positioning is down and input filed has fixed width, the dropdown covers the input field.

It should move down to the bottom edge of input field.