WPF Style BasedOn does not work - wpf

Question

I have made a style RadioButtonToggleButtonStyle as below.
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
d1p1:Ignorable="d"
xmlns:d1p1="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:TeachpendantControl">
<Style x:Key="RadioButtonToggleButtonStyle"
BasedOn="{StaticResource {x:Type ToggleButton}}"
TargetType="{x:Type RadioButton}">
<Style.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Background" Value="Gold"/>
</Trigger>
</Style.Triggers>
</Style>
</ResourceDictionary>
I use it like this below.
<ListBox Grid.Column="0" Grid.Row="0" Grid.RowSpan="10" ItemsSource="{Binding LeftPaneViewModelInfoItems, UpdateSourceTrigger=PropertyChanged}" Background="Transparent" SelectedItem="{Binding SelectedViewModelInfoItem}">
<ListBox.ItemContainerStyle>
<Style TargetType="{x:Type ListBoxItem}">
<Setter Property="Background" Value="Transparent" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ListBoxItem}">
<ContentPresenter />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListBox.ItemContainerStyle>
<ListBox.ItemTemplate>
<DataTemplate>
<RadioButton
Content="{Binding Text}"
GroupName="DisplayPage"
IsChecked="{Binding IsSelected, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ListBoxItem}}}"
Style="{StaticResource RadioButtonToggleButtonStyle}"
>
</RadioButton>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
The CheckBoxes show up as ToggleButtons when I run the application (but it shows up as CheckBoxes in Design mode).
But I don't get a gold background when the CheckBox (styled as ToggleButton) is checked. Also Visual Studio (2015) complains in the resource file saying "The resource {x:Type ToggleButton}" could not be resolved.
Can anyone provide an explanation of why this does not work (and how to solve it)

Answer 1

You need to modify the ControlTemplate to be able to change the Background of a ToggleButton.
The default ControlTemplate contains hardcoded values that take precedence over the value that you specify in your Style.
You can copy the default template into your project by right-clicking on a ToggleButton in design mode in Visual Studio or in Blend and choose Edit Template->Edit a Copy and then edit it as per your requirements. Try this:
<Style x:Key="RadioButtonToggleButtonStyle" TargetType="{x:Type ToggleButton}">
<Style.Resources>
<Style x:Key="FocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle Margin="2" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<SolidColorBrush x:Key="Button.Static.Background" Color="#FFDDDDDD"/>
<SolidColorBrush x:Key="Button.Static.Border" Color="#FF707070"/>
<SolidColorBrush x:Key="Button.MouseOver.Background" Color="#FFBEE6FD"/>
<SolidColorBrush x:Key="Button.MouseOver.Border" Color="#FF3C7FB1"/>
<SolidColorBrush x:Key="Button.Pressed.Background" Color="#FFC4E5F6"/>
<SolidColorBrush x:Key="Button.Pressed.Border" Color="#FF2C628B"/>
<SolidColorBrush x:Key="Button.Disabled.Background" Color="#FFF4F4F4"/>
<SolidColorBrush x:Key="Button.Disabled.Border" Color="#FFADB2B5"/>
<SolidColorBrush x:Key="Button.Disabled.Foreground" Color="#FF838383"/>
</Style.Resources>
<Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
<Setter Property="Background" Value="{StaticResource Button.Static.Background}"/>
<Setter Property="BorderBrush" Value="{StaticResource Button.Static.Border}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="HorizontalContentAlignment" Value="Center"/>
<Setter Property="VerticalContentAlignment" Value="Center"/>
<Setter Property="Padding" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border x:Name="border" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true">
<ContentPresenter x:Name="contentPresenter" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="Button.IsDefaulted" Value="true">
<Setter Property="BorderBrush" TargetName="border" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Background" TargetName="border" Value="{StaticResource Button.MouseOver.Background}"/>
<Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.MouseOver.Border}"/>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Background" TargetName="border" Value="{StaticResource Button.Pressed.Background}"/>
<Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.Pressed.Border}"/>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Background" TargetName="border" Value="{StaticResource Button.Disabled.Background}"/>
<Setter Property="BorderBrush" TargetName="border" Value="{StaticResource Button.Disabled.Border}"/>
<Setter Property="TextElement.Foreground" TargetName="contentPresenter" Value="{StaticResource Button.Disabled.Foreground}"/>
</Trigger>
<Trigger Property="IsChecked" Value="true">
<Setter Property="Background" TargetName="border" Value="Gold" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>