TemplateBinding not working for properties of type Color

04-30-2008 7:50 PM |

I originally posted this in the Controls forum but didn't get any replies to say that I was doing anything wrong, so I suppose that means it's probably a bug.

The problem is that TemplateBinding doesn't work with properties of type Color.  In the below example, where both the propertyName and targetProperty are dependency properties (as http://msdn.microsoft.com/en-us/library/cc189062(VS.95).aspx says that need to be), the resulting Color of the SolidColorBrush is #00000000 (an empty Color) rather than Magenta, which is the value of the BorderColour property.

To test this, I created a templated control called TestControl that inherits from Control and has a single property:

    public class TestControl : Control
    {
       public static DependencyProperty BorderColourProperty
           = DependencyProperty.Register("BorderColour", typeof(Color), typeof(TestControl), null);

       public Color BorderColour
       {
            get { return (Color)GetValue(BorderColourProperty); }
            set { SetValue(BorderColourProperty, value); }
        }
    }
 

The template from generic.xaml

    <Style TargetType="src:TestControl">
        <Setter Property="BorderColour" Value="Magenta" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="src:TestControl">
                    <Border BorderThickness="5" CornerRadius="10">
                        <Border.BorderBrush>
                            <SolidColorBrush Color="{TemplateBinding BorderColour}" />
                        </Border.BorderBrush>
                        <TextBlock Text="Give me a border colour!" />
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

When the control is rendered I get the text with no visible border; if I replace Color="{TemplateBinding BorderColour}" with Color="Magenta", I get the border as expected.

Thanks,