Answer
code
Work Step by Step
# 9.17 (Racing car) Write a program that simulates car racing, as shown in Figure
# 9.29b–d. The car moves from left to right. When it reaches the right end, it restarts
# from the left and continues the same process. Let the user increase and decrease
# the car’s speed by pressing the Up and Down arrow keys.
from tkinter import *
class MainGUI:
def __init__(self):
window = Tk()
self.canvas = Canvas(window, width=250, height=90, bg="white")
self.canvas.bind("", self.incSpeed)
self.canvas.bind("", self.decSpeed)
self.canvas.pack()
self.car = PhotoImage(file="car.gif")
x = 0
self.canvas.create_image(x, 50, image=self.car, tags="car")
self.canvas.focus_set()
self.dx = 10
while True:
self.canvas.move("car", self.dx, 0)
self.canvas.after(100)
self.canvas.update()
if x < 250:
x += self.dx
else:
x = 0
self.canvas.delete("car")
self.canvas.create_image(x, 50, image=self.car, tags="car")
window.mainloop()
def incSpeed(self, event):
if self.dx < 40:
self.dx += 5
def decSpeed(self, event):
if self.dx > 5:
self.dx -= 5
MainGUI()
