これはWindowsPhone7アプリの場合で、使用しているテンプレートコードは次のとおりです。
<Style x:Key="RadioButtonStyle1" BasedOn="{StaticResource PhoneRadioButtonCheckBoxBase}" TargetType="RadioButton">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="RadioButton">
<Grid Background="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver"/>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="EnabledCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Collapsed</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="PressedDarkCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="PressedLightCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Fill" Storyboard.TargetName="CheckMark">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneRadioCheckBoxCheckBrush}"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="EnabledCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Collapsed</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="DisabledDarkCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="DisabledLightCheckBackground">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Fill" Storyboard.TargetName="CheckMark">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneRadioCheckBoxCheckDisabledBrush}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentContainer">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneDisabledBrush}"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="CheckStates">
<VisualState x:Name="Checked">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="CheckMark">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unchecked"/>
<VisualState x:Name="Indeterminate"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Margin="{StaticResource PhoneTouchTargetLargeOverhang}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="32"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Ellipse x:Name="EnabledCheckBackground" Fill="{TemplateBinding Background}" HorizontalAlignment="Left" Height="32" IsHitTestVisible="False" VerticalAlignment="Center" Width="32"/>
<Canvas HorizontalAlignment="Left" Height="32" IsHitTestVisible="False" Opacity="{StaticResource PhoneDarkThemeOpacity}" VerticalAlignment="Center" Width="32">
<Ellipse x:Name="PressedDarkCheckBackground" Fill="{StaticResource PhoneRadioCheckBoxPressedBrush}" Height="32" Visibility="Collapsed" Width="32"/>
<Ellipse x:Name="DisabledDarkCheckBackground" Fill="{StaticResource PhoneRadioCheckBoxDisabledBrush}" Height="32" Visibility="Collapsed" Width="32"/>
</Canvas>
<Canvas HorizontalAlignment="Left" Height="32" IsHitTestVisible="False" Opacity="{StaticResource PhoneLightThemeOpacity}" VerticalAlignment="Center" Width="32">
<Ellipse x:Name="PressedLightCheckBackground" Fill="{StaticResource PhoneRadioCheckBoxPressedBrush}" Height="32" Stroke="{StaticResource PhoneForegroundBrush}" StrokeThickness="{StaticResource PhoneStrokeThickness}" Visibility="Collapsed" Width="32"/>
<Ellipse x:Name="DisabledLightCheckBackground" Fill="{StaticResource PhoneRadioCheckBoxDisabledBrush}" Height="32" Stroke="{StaticResource PhoneDisabledBrush}" StrokeThickness="{StaticResource PhoneStrokeThickness}" Visibility="Collapsed" Width="32"/>
</Canvas>
<Ellipse x:Name="CheckMark" Fill="{StaticResource PhoneRadioCheckBoxCheckBrush}" HorizontalAlignment="Center" Height="16" IsHitTestVisible="False" Visibility="Collapsed" VerticalAlignment="Center" Width="16"/>
<ContentControl x:Name="ContentContainer" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" Foreground="{TemplateBinding Foreground}" FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="12,0,146,-2" Padding="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
<Button Content="Play" Margin="0,0,2,-1" HorizontalAlignment="Right" Width="159" Click="PlayButton_Click"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
各ボタンが使用するワンクリックイベントを作成したいのですが、そのイベントハンドラー内から、クリックされているボタンを含むラジオボタンを識別できる必要があります。