WF4 is it possible to create a designer for a composite activity?

Question

I know how to hook up a designer activity to a NativeActivity or CodeActivity with the Designer attribute on the class. Like so:

[Designer(typeof(ParallelActivityDesigner))]

I would like to also hookup a designer to a composite activity (composed of some activities in only a xaml file), is that possible at all?

Answer 1

I don't exactly have this figured out myself. It should be possible but I haven't figured out the exact format the designer needs to be. The best place for info is Matt Winkler (PM on the team working on the designer) at http://blogs.msdn.com/mwinkle

Answer 2

Three known ways so far:

1. Have a code-beside .xaml.cs file, and use [DesignerAttribute], like in your question
2. [DesignerAttribute] by editing the XAML file manually
3. Using metadata registration to register custom attributes at design time, easiest in a rehosted scenario, but possible using a .Design.dll inside VS also.

(Ref Workflow Beta2 forum for details of the first 2)