In my tutorial I've been building a quadrangle editor.

The idea is that there are two menuus. One appears if I click on the background, the other if I click inside a quadrangle. In the quad menu I have options to move, resize, set color and delete the quadrangle that is being clicked. It all works ok except for the resize and move options.

Here is the menu building code that holds the critical blocks. What I'm trying to do in both cases is create a new quadrangle from the original and replace the original in the OrderedCollection which is the super class for the editor.

edit "edit a quadrangle" | menu cmdMenu quadMenu finished point actions quadActions cmdActions select qd |

quadMenu := PopUpMenu labels: 'move resize set to red delete' lines: #(3 ). quadActions := Array new: 4. quadActions at: 1 put: [:q | self at: (self whichIndex: q) put: (q translateBy: Point fromUser)]. quadActions at: 2 put: [:q | self at: (self whichIndex: q) put: (q scaleBy: Point fromUser)]. quadActions at: 3 put: [:q | q insideColor: Color red]. quadActions at: 4 put: [:q | super removeAt: (self whichIndex: q)].

whichIndex is a new method I added to the editor, and it seems to work since the remove menu action works OK. It looks like:

whichIndex: aQuad "returns index containing aQuad or nil" 1 to: lastIndex do: [:i | (self at: i) == aQuad ifTrue: [^ i]]. ^ nil

I assume I'm misunderstanding how translateBy and scaleBy work, or something? But I'm stuck. Any clues or pointers welcomed!