Data bound radio button list in WPF

Question

I have a list of options in a data object, and I want to make the equivalent of a radio button list to allow the user to select one and only one of them. Functionality similar to a databound combo box, but in radio button format.

Silly me, I thought this would be built in, but no. How do you do it?

Answer 1

Basically, after reviewing the google results, I started with the info from an MSDN discussion thread where Dr. WPF provided an answer, which talks about styling a ListBox to look right. However, when the listbox is disabled, the background was an annoying color that I couldn't get rid of for the life of me, until I read the MSDN example of the ListBox ControlTemplate, which shows the secret Border element that was kicking my background butt.

So, the final answer here was this style:

<Style x:Key="RadioButtonList" TargetType="{x:Type ListBox}">
    <!-- ControlTemplate taken from MSDN http://msdn.microsoft.com/en-us/library/ms754242.aspx -->
    <Setter Property="SnapsToDevicePixels" Value="true"/>
    <Setter Property="OverridesDefaultStyle" Value="true"/>
    <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
    <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
    <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
    <Setter Property="MinWidth" Value="120"/>
    <Setter Property="MinHeight" Value="95"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBox">
                <Border Name="Border" Background="Transparent"
                        BorderBrush="Transparent"
                        BorderThickness="0"
                        CornerRadius="2">
                    <ScrollViewer Margin="0" Focusable="false">
                        <StackPanel Margin="2" IsItemsHost="True" />
                    </ScrollViewer>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsEnabled" Value="false">
                        <Setter TargetName="Border" Property="Background"
                                Value="Transparent" />
                        <Setter TargetName="Border" Property="BorderBrush"
                                Value="Transparent" />
                    </Trigger>
                    <Trigger Property="IsGrouping" Value="true">
                        <Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <Setter Property="ItemContainerStyle">
        <Setter.Value>
            <Style TargetType="{x:Type ListBoxItem}" >
                <Setter Property="Margin" Value="2" />
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type ListBoxItem}">
                            <Border Name="theBorder" Background="Transparent">
                                <RadioButton Focusable="False" IsHitTestVisible="False"
                                             IsChecked="{TemplateBinding IsSelected}">
                                    <ContentPresenter />
                                </RadioButton>
                            </Border>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </Setter.Value>
    </Setter>
</Style>

Which provides a ControlTemplate for, and styles, the ListBox and the Items. And it gets used like this:

<ListBox Grid.Column="1" Grid.Row="0" x:Name="TurnChargeBasedOnSelector" Background="Transparent"
    IsEnabled="{Binding Path=IsEditing}"
    Style="{StaticResource RadioButtonList}"
    ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:MainForm}}, Path=DataContext.RampTurnsBasedOnList}"
    DisplayMemberPath="Description" SelectedValuePath="RampTurnsBasedOnID"
    SelectedValue="{Binding Path=RampTurnsBasedOnID, NotifyOnValidationError=True, UpdateSourceTrigger=PropertyChanged, ValidatesOnDataErrors=True, ValidatesOnExceptions=True}"/>

The more I spend time with WPF, the more I think it makes the trivial insanely difficult and the insanely difficult trivial. Enjoy. -Scott