Python Turtle.Terminator even after using exitonclick()

Question

I have tried to make functions for turtle to make it extremely easy to draw shapes and the code looks like this

import turtle as t

def square():
     tw = t.Screen()
     for i in range(4):
          t.forward(100)
          t.right(90)
     tw.exitonclick()
def triangle():
     tw = t.Screen()
     for i in range(3):
          t.forward(100)
          t.right(120)
     tw.exitonclick()
def star():
     tw = t.Screen()
     for i in range(5):
          t.forward(150)
          t.right(144)
     tw.exitonclick()

when i run this code in shell a problem is fonud...

>>> square()
>>> triangle()
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    triangle()
  File "C:\Users\Manop\Desktop\XENON\turtleg.py", line 11, in triangle
    t.forward(100)
  File "<string>", line 5, in forward
turtle.Terminator
>>> star()
>>> square()
Traceback (most recent call last):
  File "<pyshell#3>", line 1, in <module>
    square()
  File "C:\Users\Manop\Desktop\XENON\turtleg.py", line 5, in square
    t.forward(100)
  File "<string>", line 5, in forward
turtle.Terminator
>>> 

can't get over what the problem is, because i even used exitonclick()

Solution 1

I had the same error while I was working on a school project. After some research on the turtle library I have found a variable called TurtleScreen._RUNNING, if this variable is set to True a turtle window opens, if not you get the turtle.Terminator error. Every time you close a turtle screen, TurtleScreen._RUNNING is automatically set to True, if you want to avoid that, you can simply write this line of code TurtleScreen._RUNNING = True (of course you need to import turtle before).

Solution 2

Your turtle program is structured incorrectly. You needn't do:

tw = t.Screen()
...
tw.exitonclick()

in every function. Screen() only needs to be called once; exitonclick() should only ever be called once. Try this restructuring:

import turtle as t

def square():
    for i in range(4):
        t.forward(100)
        t.right(90)

def triangle():
    for i in range(3):
        t.forward(100)
        t.right(120)

def star():
    for i in range(5):
        t.forward(150)
        t.right(144)

t.penup()
t.goto(150, 150)
t.pendown()
square()

t.penup()
t.goto(-150, 150)
t.pendown()
triangle()

t.penup()
t.goto(150, -150)
t.pendown()
star()

screen = t.Screen()
screen.exitonclick()

If you want to execute the code interactively, that's fine too. Just drop everything after the function definitions, load it into Python interactively and do:

>>> star()

or whatever you want to run. You don't need the call to Screen() and the exitonclick() doesn't make sense when working interactively.

Solution 3

When you interrupt the turtle drawing, it gets angry and produces "abnormal termination" error. Use a "running" flag to stop the process at any point:

from turtle import Turtle

t=Turtle()

def square():
    global running
    t.up()
    t.setpos(-50,-50)
    t.down()
    for i in range(4):
        if not running: break; # Check 'running' here
        t.forward(100)
        t.right(90)

def triangle():
    global running
    t.up()
    t.setpos(50,50)
    t.down()
    for i in range(3):
        if not running: break; # Check 'running' here
        t.forward(100)
        t.right(120)

def star():
    global running
    t.up()
    t.setpos(-200,100)
    t.down()
    for i in range(5):
        if not running: break; # Check 'running' here
        t.forward(150)
        t.right(144)

def stop(x,y): # x,y are dummy but they are requested
  global running
  running = False  # Disable running

t.screen.onclick(stop) # Set a function for 'running'

running = True  # Enable running

square()
triangle()
star()

I tested the above code. Termination was smooth at all times.

Solution 4

Let the method screen.exitonclick() be the last statement in your code without indenting it.

You use this method when your using a Python IDE such as Pycharm, Spyder etc.

I don't know if you have heard of the method screen.mainloop()

This method enables you see the output of your code when you run it in a Python IDE.

Without this method, your output would appear in a flash.

I rewrote your code and here's mine

from turtle import Turtle

t=Turtle()

def square():
    t.up()
    t.setpos(-50,-50)
    t.down()
    for i in range(4):
        t.forward(100)
        t.right(90)

def triangle():
    t.up()
    t.setpos(50,50)
    t.down()
    for i in range(3):
        t.forward(100)
        t.right(120)

def star():
    t.up()
    t.setpos(-200,100)
    t.down()
    for i in range(5):
        t.forward(150)
        t.right(144)

square()
triangle()
star()
t.screen.exitonclick()

Here's the output output of my program

You can also check this excellent guide in Python turtle

View more solutions

Comments

[Apostolos]

Doesn't work (I have copy-pasted and run the code as it is). Clicking anywhere on he turtle screen -- even many times -- is just ignored.

[Apostolos]

Doesn't work (I have copy-pasted and run the code as it is). Clicking anywhere on he turtle screen -- even many times -- is just ignored.

[cdlane]

@Apostolos, after drawing completes, clicking anywere on the screen exits the program cleanly (in Python3). You seem to be solving a different problem: being able to exit cleanly any time during the drawing process. I don't see anything in the OP's question that implies that desire. Though that is an interesting problem, if that's what he really wants.

[Apostolos]

Yes, only when all drawing is completed and not anytime until then. This is not OK, esp. in case the drawing takes long. Please try my code below to see that you can exit anytime.

[Agguro]

It works here anyway, thanks!!! (python 3.8 in IDLE

[Admin]

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