I hit this one today - I wanted to unify the radii of corners within a Silverlight application to replace the random set of radii used (1, 2, 4, 5, 8, 10, 12, 15 and 20 pixels no less) with a simpler set - small, medium, large and massive.
The problem is that (for whatever reason), the developers of Silverlight decided that we didn't need to be able to create CornerRadius objects in our ResourceDictionaries. Or rather that we could TRY, but that the XAML Loader was never told how to deal with them. Even though the design surfaces in Visual Studio and Expression Blend can quite happily deal with this!
So if you *DO* try then you either get an error saying that you can't set the readonly TopLeft property of a CornerRadius, or if, like me, you do this in your theme.xaml you just get a catastrophic error - somewhere in your project.
So what was the solution?
Well, there was a very good answer to exactly this on Stack Overflow - using a Value Converter to read named resource values from the object for which we want to set the CornerRadius... But I suddenly realised that there was no need to have a "magic string" as keys for the TopLeft etc values - we can just use properties on the value converter ITSELF!
The result is a pretty elegant way to get around a limitation of Silverlight, thus:
<Border x:Name="
<Border.
<Binding
<Binding.
<Conve
Binding.
Binding>
Border.
…
Border>
Not quite as simple as defining a CornerRadius in a ResourceDictionary, but not bad at all - and certainly it allowed me to do what I wanted - to rationalise my myriad of Radii!
And here's the code:
namespace CheviotConsulting.Common.Silverlight.Converters
{using System.Windows;
using System.Windows.Data;
///
/// Exposes aCornerRad ius instance configuredfor a ValuationProgressButton
///
public class DynamicCornerRadiusConverter : IValueConverter
{///
/// Gets or sets thetop left.
///
///The top left.
public double TopLeft{ get; set; }
///
/// Gets or sets thetop right.
///
///The top right.
public doubleTopRight { get; set; }
///
/// Gets or sets thebottom left.
///
///The bottom left.
public doubleBottomLeft { get; set; }
///
/// Gets or sets thebottom right.
///
///The bottom right.
public doubleBottomRight { get; set; }
///
/// Gets the cornerradius.
///
/// The resourcesource.
///the corner radius
private CornerRadiusGetCornerRadius( FrameworkElement resourceSource)
{var result = new CornerRadius (this.TopLeft, this.TopRight, this.BottomRight, this .BottomLeft);
return result;
} ///
/// Modifies thesource data before passing it to the target for display in the UI.
///
/// The source data beingpassed to the target.
/// Theof data expected by the target dependency property.
/// An optionalparameter to be used in the converter logic.
/// The culture of theconversion.
///
/// The value to bepassed to the target dependency property.
///
public object Convert(object value, System.TypetargetType, object parameter,System.Globalization. CultureInfo culture)
{return this.GetCornerRadius(value as FrameworkElement );
} ///
/// Modifies thetarget data before passing it to the source object. This method is called only in cref="F:System.Windows.Data. BindingMode.TwoWay"/> bindings.
///
/// The target data beingpassed to the source.
/// Theof data expected by the source object.
/// An optionalparameter to be used in the converter logic.
/// The culture of theconversion.
///
/// The value to bepassed to the source object.
///
public objectConvertBack( object value,System. Type targetType, objectparameter, System. CultureInfoGlobalization. culture)
{throw new System.NotImplementedException ();
} }}
