Override ToggleButton Style

Question

I have a ToggleButton in my window and styled in my ResourceDictionary. The reason why it's in the ResourceDictionary is because I have several or more ToggleButton soon which has to have the same look.

<Style x:Key="Standardbutton" TargetType="{x:Type ToggleButton}">
    <Setter Property="FontSize" Value="18" />
    <Setter Property="Foreground" Value="White" />
    <Setter Property="Background">
        <Setter.Value>
            <ImageBrush ImageSource="Resources/Standard_Button_Normal.png" />
        </Setter.Value>
    </Setter>
    <Setter Property="Height" Value="56" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ToggleButton">
                <Border Name="border" BorderThickness="0" Padding="0,0" BorderBrush="DarkGray" CornerRadius="0" Background="{TemplateBinding Background}">
                    <ContentPresenter HorizontalAlignment="Left" VerticalAlignment="Center" Name="content" Margin="15,0,0,0"/>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsChecked" Value="True">
                        <Setter Property="Background">
                            <Setter.Value>
                                <ImageBrush ImageSource="Resources/Standard_Button_Pressed.png" />
                            </Setter.Value>
                        </Setter>
                        <Setter Property="Foreground">
                            <Setter.Value>
                                <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                    <GradientStop Color="#FFF9CE7B" Offset="0"/>
                                    <GradientStop Color="#FFE88C41" Offset="1"/>
                                </LinearGradientBrush>
                            </Setter.Value>
                        </Setter>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

Now this ToggleButton style has a default background and also when "IsChecked" is true, it will have different background (as you can see on my XAML code above).

Now these toggle buttons has to have icon + text combined, like what I did here (sorry for my lame XAML code)

<ToggleButton Style="{DynamicResource Standardbutton}" Margin="0,0,0,4">
    <StackPanel Orientation="Horizontal">
        <Image Source="Resources/scan_26x26.png" />
        <TextBlock Text="Scan"/>
    </StackPanel>
</ToggleButton>

The question is, how can I have a different icon when the ToggleButton is checked (IsChecked=True)?

Here are some images that might help you to understand the question

Normal ToggleButton Style

IsChecked=True Style

My design goal is to have a different icon when IsChecked=True

Answer 1

Add both images to the control template, and bind their Visibility property to the IsChecked property (use an IValueConverter to convert from true/false to the appropriate Visibility enum value).

<ToggleButton Style="{DynamicResource Standardbutton}" Margin="0,0,0,4">
    <StackPanel Orientation="Horizontal">
        <Image Source="Resources/scan_26x26.png" 
               Visibility="{Binding 
                  RelativeSource={RelativeSource AncestorType=ToggleButton},
                  Path=IsChecked,
                  Converter={StaticResource BoolToVisibleConverter}}" />
        <Image Source="Resources/anotherimage.png" 
                  Visibility="{Binding 
                     RelativeSource={RelativeSource AncestorType=ToggleButton},
                     Path=IsChecked,
                     Converter={StaticResource BoolToCollapsedConverter}}" />
        <TextBlock Text="Scan"/>
    </StackPanel>
</ToggleButton>

I used two converters BoolToVisibleConverter and BoolToCollapsedConverter, but you could also use a ConverterParameter to accomplish the same thing.