Python Tkinter动画

Question

为什么动画不起作用？运行程序时,形状不会移动.

from Tkinter import *
import time



class alien(object):
     def __init__(self):
        self.root = Tk()
        self.canvas = Canvas(self.root, width=400, height = 400)
        self.canvas.pack()
        alien1 = self.canvas.create_oval(20, 260, 120, 360, outline='white',         fill='blue')
        alien2 = self.canvas.create_oval(2, 2, 40, 40, outline='white', fill='red')
        self.canvas.pack()
        self.root.mainloop()

     def animation(self):
        track = 0
        while True:
        x = 5
        y = 0
        if track == 0:
           for i in range(0,51):
                self.time.sleep(0.025)
                self.canvas.move(alien1, x, y)
                self.canvas.move(alien2, x, y)
                self.canvas.update()
           track = 1
           print "check"

        else:
           for i in range(0,51):
                self.time.sleep(0.025)
                self.canvas.move(alien1, -x, y)
                self.canvas.move(alien2, -x, y)
                self.canvas.update()
           track = 0
        print track

alien()

Answer 1

你的animation方法有一个while True循环,永远不会破坏.这是GUI程序中的禁忌,因为从不返回,它会阻止GUI的事件循环处理事件.因此,例如,如果您有菜单,则用户将无法选择任何菜单项.除了您在animation方法中实现的任何操作外,GUI将显示为冻结状态.

这是@Tim's代码的略微修改,通过删除while循环并在返回之前简单地移动外星人一步来修复此问题.self.master.after在animation方法结束时调用,以便在短暂停顿后再次调用事件循环动画.

import tkinter as tk
import time

class Alien(object):
    def __init__(self, canvas, *args, **kwargs):
        self.canvas = canvas
        self.id = canvas.create_oval(*args, **kwargs)
        self.vx = 5
        self.vy = 0

    def move(self):
        x1, y1, x2, y2 = self.canvas.bbox(self.id)
        if x2 > 400:
            self.vx = -5
        if x1 < 0:
            self.vx = 5
        self.canvas.move(self.id, self.vx, self.vy)

class App(object):
    def __init__(self, master, **kwargs):
        self.master = master
        self.canvas = tk.Canvas(self.master, width=400, height=400)
        self.canvas.pack()
        self.aliens = [
            Alien(self.canvas, 20, 260, 120, 360,
                  outline='white', fill='blue'),
            Alien(self.canvas, 2, 2, 40, 40, outline='white', fill='red'),
        ]
        self.canvas.pack()
        self.master.after(0, self.animation)

    def animation(self):
        for alien in self.aliens:
            alien.move()
        self.master.after(12, self.animation)

root = tk.Tk()
app = App(root)
root.mainloop()

Answer 2

你从来没有打过这个animation方法.还有一些其他命名问题.

# Assuming Python 2.x
# For Python 3.x support change print -> print(..) and Tkinter to tkinter
from Tkinter import *
import time

class alien(object):
     def __init__(self):
        self.root = Tk()
        self.canvas = Canvas(self.root, width=400, height = 400)
        self.canvas.pack()
        self.alien1 = self.canvas.create_oval(20, 260, 120, 360, outline='white',         fill='blue')
        self.alien2 = self.canvas.create_oval(2, 2, 40, 40, outline='white', fill='red')
        self.canvas.pack()
        self.root.after(0, self.animation)
        self.root.mainloop()

     def animation(self):
        track = 0
        while True:
            x = 5
            y = 0
            if track == 0:
               for i in range(0,51):
                    time.sleep(0.025)
                    self.canvas.move(self.alien1, x, y)
                    self.canvas.move(self.alien2, x, y)
                    self.canvas.update()
               track = 1
               print "check"

            else:
               for i in range(0,51):
                    time.sleep(0.025)
                    self.canvas.move(self.alien1, -x, y)
                    self.canvas.move(self.alien2, -x, y)
                    self.canvas.update()
               track = 0
            print track

alien()