Changing the opacity of RadioButton text when its disabled - wpf

Question

I am trying to change the opacity of the RadioButton's Content which is some Text presumably a TextBlock. Problem is with this current style it changes the opacity of the Text just fine but it doesn't show the actual radio button itself. Please help.
<UserControl.Resources>
<Style x:Key="RadioLabel" TargetType="{x:Type RadioButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type RadioButton}">
<TextBlock x:Name="RadioLabel"
Text="{TemplateBinding Content}"
Background="{x:Null}" />
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="False">
<Setter TargetName="RadioLabel"
Property="Background"
Value="Transparent"/>
<Setter TargetName="RadioLabel"
Property="Opacity"
Value="0.5"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</UserControl.Resources>
This is my RadioButton
<RadioButton x:Name="rbn1" Style="{StaticResource RadioLabel}" GroupName="rbnApplication"
IsChecked="{Binding Path=CurrentApplicationType,
Converter={StaticResource EnumComparisonConverter},
ConverterParameter={x:Static utils:ApplicationType.QXManagerRegulatory}}"
IsEnabled="{Binding Path=CurrentApplicationType,
Converter={StaticResource EnumComparisonConverter},
ConverterParameter={x:Static utils:ApplicationType.QXManagerRegulatory}}"
Content="QX Manager Regulatory"/>

Answer 1

In general the easiest way to achieve this is to declare a RadioButton (or any other control) and then in the properties tab go to the Miscellaneous -> Template, left-click on the little square button on the right and choose "Convert to local value". This will expand the full existing ControlTemplate, which you can then edit and/or add triggers to etc:
<RadioButton x:Name="template" >
<RadioButton.Template>
<ControlTemplate TargetType="{x:Type RadioButton}">
<Grid x:Name="templateRoot" Background="Transparent" SnapsToDevicePixels="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Border x:Name="radioButtonBorder" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="100" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="1,1,2,1" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid x:Name="markGrid" Margin="2">
<Ellipse x:Name="optionMark" Fill="#FF212121" MinWidth="6" MinHeight="6" Opacity="0"/>
</Grid>
</Border>
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" ContentStringFormat="{TemplateBinding ContentStringFormat}" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasContent" Value="True">
<Setter Property="FocusVisualStyle">
<Setter.Value>
<Style>
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle Margin="14,0,0,0" SnapsToDevicePixels="True" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Setter.Value>
</Setter>
<Setter Property="Padding" Value="4,-1,0,0"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" TargetName="radioButtonBorder" Value="#FFF3F9FF"/>
<Setter Property="BorderBrush" TargetName="radioButtonBorder" Value="#FF5593FF"/>
<Setter Property="Fill" TargetName="optionMark" Value="#FF212121"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Background" TargetName="radioButtonBorder" Value="#FFE6E6E6"/>
<Setter Property="BorderBrush" TargetName="radioButtonBorder" Value="#FFBCBCBC"/>
<Setter Property="Fill" TargetName="optionMark" Value="#FF707070"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Background" TargetName="radioButtonBorder" Value="#FFD9ECFF"/>
<Setter Property="BorderBrush" TargetName="radioButtonBorder" Value="#FF3C77DD"/>
<Setter Property="Fill" TargetName="optionMark" Value="#FF212121"/>
</Trigger>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Opacity" TargetName="optionMark" Value="1"/>
</Trigger>
<Trigger Property="IsChecked" Value="{x:Null}">
<Setter Property="Opacity" TargetName="optionMark" Value="0.56"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</RadioButton.Template>
</RadioButton>

Answer 2

This is because you're setting ControlTemplate to your RadioButton. Which changes your whole control. Instead you need to use ContentTemplate to change your Content.
Below Style should work for your case.
<Style x:Key="RadioLabel" TargetType="{x:Type RadioButton}">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate DataType="{x:Type RadioButton}">
<TextBlock x:Name="RadioLabel"
Text="{TemplateBinding Content}"
Background="{x:Null}" />
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding Path=IsChecked,
RelativeSource={RelativeSource Mode=TemplatedParent}}"
Value="False">
<Setter TargetName="RadioLabel"
Property="Background"
Value="Transparent"/>
<Setter TargetName="RadioLabel"
Property="Opacity"
Value="0.5"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>