Add alternation color to the drop-down items of RadComboBox

Environment

Product Version	2020.3 1116
Product	RadComboBox for WPF

Description

How to add alternation color to the items inside the drop-down content of RadComboBox control.

Solution

To add alternation color to the items inside the drop-down content you can take advantage of the AlternationCount property. This property comes from the native ItemsControl class. As the RadComboBox inherits ItemsControl you can take advante of this funtionality.

The following example demonstrates how to use this property and how to apply custom color to the alternation items.

<telerik:RadComboBox AlternationCount="2" ItemsSource="{Binding Data}" DisplayMemberPath="Name"> 
    <telerik:RadComboBox.ItemContainerStyle> 
        <Style TargetType="telerik:RadComboBoxItem"> 
            <Style.Triggers> 
                <Trigger Property="ItemsControl.AlternationIndex" Value="0"> 
                    <Setter Property="Background" Value="Bisque"/> 
                    <Setter Property="Foreground" Value="Purple"/> 
                </Trigger> 
                <Trigger Property="ItemsControl.AlternationIndex" Value="1"> 
                    <Setter Property="Background" Value="LightBlue"/> 
                    <Setter Property="Foreground" Value="Navy"/> 
                </Trigger> 
            </Style.Triggers> 
        </Style> 
    </telerik:RadComboBox.ItemContainerStyle> 
</telerik:RadComboBox>