XAML Automatic Type Conversion

Question

I've noticed it's possible to return a string like "Visible", "Collapsed", "Images/xyz.png" or "#FFB3D1" from a value converter and the magic of bindings manages to figure it out. Hide/Show the UI Element, find the xyz.png image or colour something pink...

I've taken this for granted for a long time, it now it doesn't work with my latest code, So my Question is how can I manually call this functionality?

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Explanation:

I've scaled up by creating a custom MarkupExtension, which attaches a MultiConverter attaches it to a MultiBinding and returns the initialised binding. However when this multi converter returns strings like "#FFB3D1" or "Red", nothing seems to happen.

// PseudoCode from my MarkupExtension, setting up & returning the binding/multi-converter
public override object ProvideValue( IServiceProvider serviceProvider )
{
    MultiBinding outputBinding = new MultiBinding();    
    foreach ( Binding b in bindings )
    {
        outputBinding.Bindings.Add( b );
    }    

    outputBinding.Converter = converter;
    return outputBinding.ProvideValue( serviceProvider );
}

I presume that because I'm creating the Multibinding + Converter in code, it's skipping a step somewhere in the Binding.Magic namespace.

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Solution:

    public override object ProvideValue( IServiceProvider serviceProvider )
    {
        // get targets
        IProvideValueTarget serv = (IProvideValueTarget)serviceProvider.GetService( typeof( IProvideValueTarget ) );

        // get Type Converter
        object[] typeConverterAttributes = ( (DependencyProperty)serv.TargetProperty ).PropertyType.GetCustomAttributes( typeof( TypeConverterAttribute ), true );
        TypeConverter typeConverter = null;

        if ( typeConverterAttributes.Length > 0 )
        {
            TypeConverterAttribute attr = (TypeConverterAttribute)typeConverterAttributes[0];
            typeConverter = (TypeConverter)Activator.CreateInstance( Type.GetType( attr.ConverterTypeName ), false );
        }

It is then simply a case of applying the Type Converter manually

Answer 1

Maybe you can try a BrushConverter.