Binding a converter to a MultiBinding in Silverlight

Question

The Converter property in the code from the blog post, Silverlight MultiBinding solution for Silverlight 4, is not a dependency property, so I can't bind it with a converter (that for technical reasons must be instantiated as part of Unity injection earlier in the application rather than as a simple static resource as part of a user control).

How can I modify the MultiBinding code to accept a bound converter? I tried to make it a dependency property:

public IMultiValueConverter Converter { get { return (IMultiValueConverter)GetValue(ConverterProperty); } set { SetValue(ConverterProperty, value); } }
public static DependencyProperty ConverterProperty = DependencyProperty.Register("Converter", typeof(IMultiValueConverter), typeof(IMultiValueConverter), null);

but I got

DependencyProperty System.Windows.Data.IMultiValueConverter. Converter cannot be set on an object of type ...Binding.MultiBinding.

If this is not a viable option, how can I bind the ConverterParameter property or get something to simulate bindings of a converter to a MultiBinding?

Answer 1

I solved this using the "simulated bindings" route, though that's not my preference if someone has another answer. What I did instead was not build up the converter via dependency injection, but instead had it use service location to get it's needed dependencies. Generally I prefer dependency injection to service location. The "service location" was a matter of storing the Unity container in the application's global resources; from there it's not difficult to get what I need.