为什么对象在Zelle图形中不停止移动？

Question

from graphics import *
win = GraphWin("Circle Race", 500, 500)

#red circle position
RcenterX = 50
RcenterY = 100
Rright = RcenterX+25
Rleft = RcenterY

# The Red circle
cr = Circle(Point(RcenterX,RcenterY), 25)
cr.setFill('red')
cr.setOutline('black')
cr.draw(win)


if RcenterX<=400:
    win.getMouse()
    cr.move(50 ,0)
elif RcenterX>300:
    win.getMouse()
    win.close()

我尝试在每次点击后移动红色圆圈50个像素，当圆圈的右边缘达到400时停止。 但它在达到400后继续移动？ 我怎么能在400停下来？你知道吗

Answer 1

两个基本更改：您的if语句需要是while循环；您需要重新计算RcenterX，可以自己更新它，也可以询问您的circle对象：

from graphics import *

win = GraphWin("Circle Race", 500, 500)

# red circle position
RcenterX, RcenterY = 50, 100
Rradius = 25

# The Red circle
cr = Circle(Point(RcenterX, RcenterY), Rradius)
cr.setFill('red')
cr.setOutline('black')
cr.draw(win)

while cr.getCenter().getX() + Rradius/2 < 400:  # right edge stops at 400
    win.getMouse()
    cr.move(50, 0)

win.getMouse()
win.close()