You can fine-tune how the shape part works in the Composition Editor by creating your own edit part. An edit part is a special class that is used by the Composition Editor to control the part's pop-up menu and other special behavior during editing.
Begin by creating a new class:
The class definition should look like the following:
AbtCompositeEditPart subclass: #MyShapeEditPart instanceVariableNames: '' classVariableNames: '' poolDictionaries: ''
Create a link between the shape part and the edit part by implementing the editPartClass class method in MyShape. Move this method to MyEditSamplePartsApp.
editPartClass "Answer my edit part's class name." ^MyShapeEditPart