Python Forum

I cant move the paddle in this game and yes i am focused on the game screen when i press the left and right arrow. Also there is no error message. I am doing the bounce game from the python book. I didn't see anything wrong it.video of program In this video you can't see it but im pushing down the arrows.

import time
import random
from tkinter import *

class Ball:
    def __init__(self, canvas, color):
        self.canvas = canvas
        self.id = canvas.create_oval(10, 10, 25, 25, fill=color)
        self.canvas.move(self.id, 245, 100)
        starts = [-3, -2, -1, 1, 2, 3]
        random.shuffle(starts)
        self.x = starts[0]
        self.y = -3
        self.canvas_height = self.canvas.winfo_height()
        self.canvas_width = self.canvas.winfo_width()
		
    def draw(self):
        self.canvas.move(self.id, self.x, self.y)
        pos = self.canvas.coords(self.id)
        if pos[1] <= 0:
            self.y = 1
        if pos[3] >= self.canvas_height:
            self.y = -1
        if pos[0] <= 0:
            self.x = 3
        if pos[2] >= self.canvas_width:
            self.x = -3

class Paddle:
    def __init__(self, canvas, color):
        self.canvas = canvas
        self.id = canvas.create_rectangle(0, 0, 100, 10, fill=color)
        self.canvas.move(self.id, 200, 300)
        self.x = 0
        self.canvas_width = self.canvas.winfo_width()
        self.canvas.bind_all('KeyPress-Left', self.turn_left)
        self.canvas.bind_all('KeyPress-Right', self.turn_right)

    def draw(self):
        self.canvas.move(self.id, self.x, 0)
        pos = self.canvas.coords(self.id)
        if pos[0] <= 0:
            self.x = 0
        elif pos[2] >= self.canvas_width:
            self.x = 0

    def turn_left(self, evt):
        self.x = -2

    def turn_right(self, evt):
        self.x = 2
        
tk = Tk()
tk.title("Game")
tk.resizable(0, 0)
tk.wm_attributes("-topmost", 1)
canvas = Canvas(tk, width=400, height=400, bd=0, highlightthickness=0)
canvas.pack()
tk.update()

paddle = Paddle(canvas, 'blue')
ball = Ball(canvas, 'red')

while 1:
        ball.draw()
        paddle.draw()
        tk.update_idletasks()
        tk.update()
        time.sleep(0.01)
 

	

General, simple debugging would be to print self.x in the Paddle class, draw function before this line

self.canvas.move(self.id, self.x, 0)

I don't get what you mean by that

printing variables is straight forward and one way to find errors. What was printed when you added the print statement at the specified place?

## add the print statement in this function
    def draw(self):
        self.canvas.move(self.id, self.x, 0)
        pos = self.canvas.coords(self.id)
        if pos[0] <= 0:
            self.x = 0
        elif pos[2] >= self.canvas_width:
            self.x = 0  

it was printing 0 over and over again