Detecting a click on the turtle screen when the turtle isn't doing anything?

[Adam Funk]

I'm trying to get a program to do some plotting with turtle graphics,
then wait for the user to click on the graphics window, then do some
more plotting, &c.  So far I have the following, which doesn't work:

#v+
waiting = False

def clicked(x, y):
    global waiting
    print('clicked at %f %f' % (x,y))
    waiting = False
    return

def wait_for_click(s):
    global waiting
    waiting = True
    s.listen()
    while waiting:
        time.sleep(1)
    return


...
t = turtle.Pen()
s = turtle.Screen()
...
traverse.plot(s, t, "black", scale, adjx, adjy)
wait_for_click(s)
bowditch.plot(s, t, "red", scale, adjx, adjy)
wait_for_click(s)
transit.plot(s, t, "blue", scale, adjx, adjy)
wait_for_click(s)
#v-


Each of my plot(..) calls does some turtle movement, and I want the
program to sit and wait for the user to click the graphics window,
then add the next plot.  I've played around with some event handling
examples I found [1], and concluded that the onclick binding only
works while the turtle is doing something.  Is that correct?  Is there
a way to wait for the click & hear it while the turtle is not doing
anything?


[1] <http://csil-web.cs.surrey.sfu.ca/cmpt120fall2010/wiki/IntroToEventHandling/>


Thanks,
Adam


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Establishment; it makes them feel educated.         [Robert Graves]