Dave, when I create new morph classes, I usually subclass PasteUpMorph. If I need it in a window, I call #openInWindow on a new instance, though I find that first putting it in a ScrollPane makes for more useful behavior -usually. Regardless, the #step and #stepAt: calls work as expected when you use a PasteUpMorph subclass since you get the same behavior as you get from World. Lawson On 2/4/12 10:33 AM, Dave Mason wrote:

Hi,

I want to build a morphic application (for algorithm animation) so I need to do something in the step method.

I wanted to make it a subclass of SystemWindow (I'd actually prefer StandardWindow in Pharo but there doesn't appear to be an equivalent in Squeak). But when I do, the step method doesn't get called. (Nor does stepAt:) (And StandardWindow behaves the same.).

But if I move it to MorphicModel step/stepAt: gets called, but I don't get any of that SystemWindow goodness.

I've looked at the dispatch in Morph, and I don't see anything different in Worldstate>>runLocalStepMethodIn: but this stuff is very difficult to debug, because there's asynchronous stuff running behind the scenes. In particular, lastStepMessage value: now. lastStepMessage ifNotNil: [... is a little weird!

Any pointers appreciated.

Thanks ../Dave