# Tk_bouncing_balls_demo.py

# Tk_bouncing_balls_demo.py

from Tkinter import *
import random
import time

class Ball:
    def __init__(self, canvas, color, size):
        self.canvas = canvas
        self.id = canvas.create_oval(10,10,size,size, fill=color)
        self.canvas.move(self.id, 245, 100)
        self.yspeed = random.randrange(1,9)
        self.xspeed = random.randrange(1,9)
        self.yspeed *= random.choice([1,-1])
        self.xspeed *= random.choice([1,-1])

    def draw(self):
        self.canvas.move(self.id, self.xspeed, self.yspeed)
        pos = self.canvas.coords(self.id)
        if pos[0] <= 10:
            self.xspeed = random.randrange(1,9)
        elif pos[2] >= 510:
            self.xspeed = -(random.randrange(1,9))
        if pos[1] <= 10:
            self.yspeed = random.randrange(1,9)
        elif pos[3] >= 410:
            self.yspeed = -(random.randrange(1,9))

tk = Tk()
tk.title("Bouncing Balls Demo")
canvas = Canvas(tk, width=520, height=420, bd=0)
canvas.pack()

ball_list = []
color_list = ['red', 'blue', 'purple', 'yellow', 'orange','green']
for i in range (40):
    color = random.choice(color_list)
    size = random.randrange(20,100)
    ball_list.append(Ball(canvas, color, size))

while True:
    try:
        for ball in ball_list:
            ball.draw()
        tk.update()
    except: break
    time.sleep(0.01)