Python using turtle button

Question

I am attempting for a homework assignment to implement Simon Says in python. I'm trying to do it using the turtle library (a requirement).

However, I've run into a stumbling block in that while I can get the screen to register click events (currently just printing the x,y coordinates) I can't get it to wait for a click event.

Specifically what I'm planning on doing is having areas on the screen that when they click within that location it is considered as if they had clicked a button. Screen clears and game does whatever.

However, in experiments in trying to get a working 'button' all that it does is set it so it prints the x,y coordinates but the rest of the program finishes. Didn't wait for the user to click anything. I tried a blocking method of...

while clicked == False:
    pass

or

while clicked == False:
    time.sleep(1)

but both methods hangs the program until I manually interrupt and then it'll print the clicks.

Am I missing an option somewhere?

Answer 1

So after extensive search there isn't necessarily a way pause execution of the code in python while using turtle to wait for some click event. Maybe in Tk I could do that but not in turtle.

However, there is a way to get around that. As an example. A method sets up the fake button on the screen, sets the click event, and terminates. The click event when clicked calls the next method needed for execution. So until the button is clicked the actual code isn't doing anything but remains in memory for use.

So more specifically. 1. Create a 'button'. 2. Have your program behave normally until it needs to wait for a click event. 3. Set up the on screen click (or on turtle) in such a way when the 'button' is clicked the next part of the code is run.

Special note. The code in question can't depend on waiting for a click event for later on in code. Instead, the click causes the next part of the execution of your code.

Answer 2

Turtles don´t have buttons, but they do have callbacks for clicks. Furthermore, you should use onclick for Screen to detect general clicks and onclick for turtle to detect clicking in turtles. You can, for example, make a 4 BIG turtles with different colors by using a dynamic shape.

Also, turtle is based on Tk, so you must be aware of things like mainloop()

The following program give some hints for Python 2.7.5.

import turtle as t
from random import randint

class MyTurtle(t.Turtle) :

    def __init__(self,**args) :
        t.Turtle.__init__(self,**args)

    def mygoto(self,x,y) :
        t1.goto(x,y)
        print x,y

    def randonics(self,x,y) :
        self.left(randint(90,270))

def minegoto(x,y) :
    print x,y
    t1.goto(x,y)

wt=t.Screen()
t1=MyTurtle()
wt.register_shape("big",((0,0),(30,0),(30,30),(0,30)))
t1.shape("big")
wt.onclick(t1.mygoto,btn=1)
wt.onclick(minegoto,btn=2)
t1.onclick(t1.randonics,btn=3)
t1.goto(100,100)

t.mainloop()

Answer 3

You can make the function registered with onclick() test the x,y position. If it is inside some region you do whatever you must.

I don´t see the difference between what you want to do and what this code does, the modification of turtle position is just an example, you can do anything when a click is captured by onclick(), even start a thread if you really need it (using Creating Threads in python)

import turtle as t
from random import randint
from threading import Thread
from time import sleep

def threaded_function(arg,t1):
    for i in range(arg):
        print "running",i
        sleep(1)
        t1.forward(i*10)



def minegoto(x,y) :
    print x,y
    t1.goto(x,y)
    thread = Thread(target = threaded_function, args = (10,t1 ))
    thread.start()
    thread.join()
    print "thread finished...exiting"

wt=t.Screen()
t1=t.Turtle()
wt.register_shape("big",((0,0),(30,0),(30,30),(0,30)))
t1.shape("big")
wt.onclick(minegoto,btn=1)
t1.goto(100,100)

t.mainloop()