Currently filtering with virtualized RadComboBox is not supported as the filtering feature works with the containers (changes their Visibility).

Add NoResultsContent and NoResultsContentTemplate properties to the RadComboBox control. 

Currently, the drop down of RadComboBox contains only the RadComboBoxItems and the Clear Selection button. Add new content presenter that allows you to include extra visuals, like buttons or text.

The feature is similar to the AdditionalContent of RadTabControl. 

The RadComboBox control could provide SelectAll button or template functionality. This way the user can choose whether to use the default button or create a custom select all behavior.

In this case, the control is bound to a collection of strings. The collection contains equal string values. ("h1","h2","h1"). When the first item is selected and afterward we select the last one, will not trigger the SelectionChanged event. This behavior could be improved.

 

Currently, the first filtered item of the control is selected once a search (with IsTextSearchEnabled=True) is performed. Users should be able to control whether this happens or if the selection needs to be skipped.

Currently, the EmptyText is shown in a TextBlock which cannot be customized. Add a EmptyTextContent or EmptyTextVisualStyle properties to allow customizing the UI of the empty text. 

The RadListBox has an attached property for mvvm binding of SelectedItems - https://docs.telerik.com/devtools/wpf/controls/radlistbox/features/selecteditemssource.

 

Please support SelectedItemsSource for RadComboxBox too.

The OnLostFocus is triggered when the control gets the focus and is not triggered after the focus is lost. The current call stack is as follows:
- The control gets the focus 
- OnGotFocus is hit
- OnLostFocus is hit incorrectly
- The focus is removed from the control
- The OnLostFocus is not hit and it should be

As a workaround you can hook to these events in the constructor of the custom ComboBox:

    public MyRadComboBox()
    {
        this.GotFocus += MyRadComboBox_GotFocus;
        this.LostFocus += MyRadComboBox_LostFocus;
    }

Currently the control scrolls by group.

This would provide the option to stop the auto scrolling when the last item is hovered.

Enable the ComboBox to open its DropDown in up as well as down direction

When "TextSearchMode" is set to "Contains", IsEditable="True" and IsReadOnly="True": it should be possible to select all or some of the text and by pressing delete or backspace the selected text should be removed.