Hello everyone,
I've been learning python since the past few days.
I have tried several ways but nothing seems to work!!
All I want to do is, randomly generate some moving ovals after some regular or irregular interval of time. I have tried canvas.after but it didnâ€™t worked.
The ovals should stop when the lights are red.
I would be really grateful if anyone could help me out. Thanking you in advance.
Here is the code:

``````import Tkinter as tk
import time
import sys
import datetime as dt
from Tkinter import *
import random

class TrafficLight(tk.Frame):
"""inherits tk.Frame"""
def __init__(self, parent=None):
tk.Frame.__init__(self, parent, bg='green')

def make_widgets(self,x1,y1,x2,y2):
canvas.create_rectangle(x1,y1,x2,y2)
canvas.create_oval(x1+5, y1+5, x2-5, y2-22, fill='red')
canvas.create_oval(x1+5, y1+22, x2-5, y2-5, fill='white')

def red_light(self):
canvas.create_oval(173,106,185,118, fill='red')
canvas.create_oval(173,123,185,135, fill='white')
#canvas.create_oval(x1, y1+19, x2, y2+19, fill='yellow')
#canvas.create_oval(x1, y1, x2, y2, fill='green')
self.after(5000,self.green_light)
self.green_light_on = False

def green_light(self):

#canvas.create_oval(x1, y1, x2, y2, fill='red')
#canvas.create_oval(x1, y1+19, x2, y2+19, fill='yellow')
canvas.create_oval(173,123,185,135, fill='green')
canvas.create_oval(173,106,185,118, fill='white')
self.after(5000,self.red_light)
self.green_light_on = True

def red_light1(self):
canvas.create_oval(347,106,359,118, fill='red')
canvas.create_oval(347,123,359,135, fill='white')
#canvas.create_oval(x1, y1+19, x2, y2+19, fill='yellow')
#canvas.create_oval(x1, y1, x2, y2, fill='green')
self.after(5000,self.green_light1)
self.green_light_on1 = False

def green_light1(self):

#canvas.create_oval(x1, y1, x2, y2, fill='red')
#canvas.create_oval(x1, y1+19, x2, y2+19, fill='yellow')
canvas.create_oval(347,123,359,135, fill='green')
canvas.create_oval(347,106,359,118, fill='white')
self.after(5000,self.red_light1)
self.green_light_on1 = True

class Car(object):
def __init__(self, a,b,c,d, outline='blue', fill='blue'):
self.rect = canvas.create_oval(a,b,c,d, outline=outline, fill=fill)
self.speed = (0, 0)

def set_speed(self, x, y):
self.speed = x, y

def move(self):
canvas.move(self.rect, self.speed[0], self.speed[1])
self.light = TrafficLight()
red1=canvas.coords(canvas.create_oval(173,106,185,118))
red2=canvas.coords(canvas.create_oval(347,106,359,118))
vehicle=canvas.coords(self.rect)

if vehicle < red1:
red11=canvas.coords(canvas.create_oval(168,81,180,93, fill= "white",outline= "red"))

if light.green_light_on:
self.speed=3,0

elif not light.green_light_on:
self.speed=0,0
if vehicle<red11:
self.speed=3,0

if  (vehicle > red1 and red2>vehicle):
red22=canvas.coords(canvas.create_oval(342,81,354,93, fill= "white",outline= "red"))
if light.green_light_on1:
self.speed=3,0

elif not light.green_light_on1:
self.speed=0,0

if vehicle<red22:
self.speed=3,0

root=tk.Tk()
root.title("Traffic Simulation")
canvas = tk.Canvas(root, width=1000, height=400, bg="#FFFFFF")
canvas.pack()

l1=canvas.create_line(140,150,200,150,
200,150,200,50, width=3)
l2=canvas.create_line(250,150,250,50,
250,150,374,150,
374,150,374,50, width=3)

l6=canvas.create_line(140,200,200,200,
200,200,200,300, width=3)
l7=canvas.create_line(250,200,250,300,
250,200,344,200,
344,200,344,300, width=3)

rect=canvas.create_rectangle(140,152,850,198, fill="#999999", outline="#999999")
rect1=canvas.create_rectangle(202,50,248,300, fill="#999999", outline="#999999")
rect2=canvas.create_rectangle(376,50,422,152, fill="#999999", outline="#999999")
rect3=canvas.create_rectangle(346,198,392,300, fill="#999999", outline="#999999")

light = TrafficLight()

light.make_widgets(168, 101, 190, 140)
light.make_widgets(342, 101, 364, 140)

y=light.red_light()
y1=light.red_light1()

car1 = Car(20, 155, 40, 170, outline='blue', fill='blue')
car2 = Car(20, 175, 40, 190, outline='red', fill = 'red')
car3 = Car(40, 180, 60, 195, outline='Yellow', fill = 'Green')

# move car
while True:

car1.move()
canvas.after(10000,car2.move)
car3.move()

canvas.update()

root.mainloop()``````

Your cars are initialized with a speed of 0, 0. You should call their `set_speed` method to define another value. If you don't start the cars, they won't move !

i tried but this didn't solved my problem!!!!
i would be thankful if anyone could post a simple example where a new oval is continuously created after a random period of time( e.g A new moving oval is created after every 10 -15 seconds), and is destroyed when it reaches a particular X or Y coordinate.