1#!/usr/bin/env python3 2""" turtle-example-suite: 3 4 tdemo_paint.py 5 6A simple event-driven paint program 7 8- left mouse button moves turtle 9- middle mouse button changes color 10- right mouse button toogles betweem pen up 11(no line drawn when the turtle moves) and 12pen down (line is drawn). If pen up follows 13at least two pen-down moves, the polygon that 14includes the starting point is filled. 15 ------------------------------------------- 16 Play around by clicking into the canvas 17 using all three mouse buttons. 18 ------------------------------------------- 19 To exit press STOP button 20 ------------------------------------------- 21""" 22from turtle import * 23 24def switchupdown(x=0, y=0): 25 if pen()["pendown"]: 26 end_fill() 27 up() 28 else: 29 down() 30 begin_fill() 31 32def changecolor(x=0, y=0): 33 global colors 34 colors = colors[1:]+colors[:1] 35 color(colors[0]) 36 37def main(): 38 global colors 39 shape("circle") 40 resizemode("user") 41 shapesize(.5) 42 width(3) 43 colors=["red", "green", "blue", "yellow"] 44 color(colors[0]) 45 switchupdown() 46 onscreenclick(goto,1) 47 onscreenclick(changecolor,2) 48 onscreenclick(switchupdown,3) 49 return "EVENTLOOP" 50 51if __name__ == "__main__": 52 msg = main() 53 print(msg) 54 mainloop() 55