drawing with the mouse with turtle

[Steven D'Aprano]

On Sat, 13 Nov 2010 06:22:59 -0500, Brian Blais wrote:

> there is no change by changing the order, but I didn't expect one. 
> since ondrag is binding a callback, which is only called when the event
> happens, I figure that the pen has to be down when the callback happens,
> not when the binding occurs.  since the pen is down (and never lifted),
> when I start dragging the mouse around after that it should work...but
> doesn't seem to.

Can you tell if your callback is being called at all?

In other words, can you distinguish between these?

* the callback isn't being called;

* the callback is being called, but nothing is being drawn.


-- 
Steven