python tkinter中的移动图像

Question

我正在编写一个简单的程序，我希望（球图像 png）在其中从墙上反弹。到目前为止，我已经写了这段代码：

import tkinter as tk

root = tk.Tk()

WIDTH = 500
HEIGHT = 500

canvas = tk.Canvas(root,bg="white",width=WIDTH,height=HEIGHT)
canvas.pack()

img = tk.PhotoImage(file="images/ball1.png")
ball = canvas.create_image(0,0,anchor="nw",image=img)

yspeed = 2
xspeed = 2

def move_ball():
    global xspeed,yspeed,ball
    canvas.move(ball,xspeed,yspeed)
    canvas.after(10,move_ball)

move_ball()
root.mainloop()

Answer 1

您可以使用coords 方法获取当前位置，然后对 4 面墙中的每面进行检查。这是第一个：

def move_ball():
    global xspeed,yspeed,ball
    xpos, ypos = canvas.coords(ball)
    if xpos + width_of_ball > WIDTH:
        # ball hit the right edge, reverse x direction
        xspeed *= -1
    canvas.move(ball,xspeed,yspeed)
    canvas.after(10,move_ball)

Answer 2

此答案与@Novel 答案相同（尽管我在看到他们的答案之前就写了它）。唯一的区别在于update 的逻辑并不期望您对其进行任何编辑，它会考虑水平和垂直方向，并且会补偿调整主窗口的大小。

import tkinter as tk

root = tk.Tk()
root.title('Infinite Bounce Simulator')
root.geometry('400x300+300+300')

xspeed = 4
yspeed = 3

canvas = tk.Canvas(root, highlightthickness=0, bg='#111')
canvas.pack(expand=True, fill='both')    

ball   = canvas.create_oval((0, 0, 20, 20), fill='red')

def update():
    global xspeed, yspeed, ball
    
    canvas.move(ball, xspeed, yspeed)
    
    #Left, Top, Right, Bottom coordinates
    l, t, r, b = canvas.coords(ball)
    
    #flip speeds when edges are reached
    if r > canvas.winfo_width()  or l < 0:
        xspeed = -xspeed 
    if b > canvas.winfo_height() or t < 0:
        yspeed = -yspeed           
        
    #do it all again in 10 milliseconds
    root.after(10, update)
    
    
root.after_idle(update)    
root.mainloop()