I have a Form where I change pixel colours using Form>>pixelValueAt:put:. The Form exists inside an SpImagePresenter. After having changed the pixels, I want to redraw the Form in an #updatePresenters method to show the changes, but I haven't been able to figure out how to do this. If I inspect the Form it is clear that the pixels have been changed, so the problem is in the #updatePresenters mwthod. I have tried different variations on this theme without success: updatePresenter | canvas | "Get the canvas of the Form:" canvas := imagePresenter image form getCanvas. adapter widget drawSubmorphsOn: canvas Any suggestions would be very welcome. Kind regards, Mikael