如何在Tkinter中实现画布项目的SMOOTH运动?

时间:2014-09-30 17:37:08

标签: python tkinter

我正在尝试在Tkinter中使用键盘驱动的事件,以便我可以在画布小部件周围移动一个对象。向上,向下,向左和向右工作正常但是当我尝试将两个键编程在一起时,运动不是平滑的对角线运动。此外,每当一个键被击中时,物体就会移动,然后会有轻微的延迟,然后它会平稳地移动。 如何实现平滑运动按下按键,如何实现平滑的对角运动?

这是到目前为止的代码:

from tkinter import *

x = 10
y = 10
a = 100
b = 100

def change_coord(event):
        if event.keysym == 'Up':
            canvas1.move(rect, 0,-5)
        if event.keysym == 'Up' and 'Right':
            canvas1.move(rect, 5,-5)
        if event.keysym == 'Up' and 'Left':
            canvas1.move(rect, -5,-5)
        if event.keysym == 'Down':
            canvas1.move(rect, 0,5)
        if event.keysym == 'Down' and 'Right':
            canvas1.move(rect, 5,5)
        if event.keysym == 'Down' and 'Left':
            canvas1.move(rect, -5,5)
        if event.keysym == 'Right':
            canvas1.move(rect, 5,0)
        if event.keysym == 'Left':
            canvas1.move(rect, -5,0)

window = Tk()
window.geometry("400x200")

#canvas and drawing
canvas1=Canvas(window, height = 200, width = 400)
canvas1.grid(row=0, column=0, sticky=W)
coord = [x, y, a, b]
rect = canvas1.create_rectangle(*coord, outline="#fb0", fill="#fb0")

#capturing keyboard inputs and assigning to function
window.bind_all('<Up>', change_coord)
window.bind_all('<Down>', change_coord)
window.bind_all('<Left>', change_coord)
window.bind_all('<Right>', change_coord)
window.mainloop()

非常感谢!

修改

感谢您的所有建议。我一直试图实现一个动画循环来解决箭头键后的轻微延迟,但现在卡住了。我的新代码如下所示,但运行程序不会导致画布项目移动。首先,是动画循环正确的想法,其次我在哪里调用'移动'功能来让项目移动。请帮忙 - 谢谢!

from tkinter import *

x = 10
y = 10
a = 100
b = 100
direction = None

def move():
    global x_vel
    global y_vel
    global direction
    if direction is not None:
        canvas1.move(rect, x_vel,y_vel)
        after(33,move)

def on_keypress(event):
    global direction
    global x_vel
    global y_vel
    if event.keysym == "Left":
        direction == "left"
        x_vel = -5
        y_vel = 0
    if event.keysym == "Right":
        direction == "right"
        x_vel = 5
        y_vel = 0
    if event.keysym == "Down":
        direction == "down"
        x_vel = 0
        y_vel = 5
    if event.keysym == "Up":
        direction == "up"
        x_vel = 0
        y_vel = -5

def on_keyrelease(event):
    global direction
    direction = None


window = Tk()
window.geometry("400x200")

#canvas and drawing
canvas1=Canvas(window, height = 200, width = 400)
canvas1.grid(row=0, column=0, sticky=W)
coord = [x, y, a, b]
rect = canvas1.create_rectangle(*coord, outline="#fb0", fill="#fb0")

#capturing keyboard inputs and assigning to function
window.bind_all('<KeyPress>', on_keypress)
window.bind_all('<KeyRelease>', on_keyrelease)
window.mainloop()

1 个答案:

答案 0 :(得分:2)

绑定到基本键是错误的方法。相反,绑定到按键和按键释放,并使用它来创建按键的字典。每N ms运行一个使用该字典确定如何移动对象的函数。 (我不确定Tkinter计时器是否具有正确执行此操作所需的质量。)

如果程序失去焦点,请务必清除字典。