Turtle中的按键事件导致其他按键事件停止工作

Question

我正试着用海龟做一个非常基础的MS-Paint版本。我有几个按键和鼠标事件，但有一个按键事件，即turtle.width的turtle.numinput()，在我输入所需的笔宽整数后，会导致其他按键事件停止工作。不过，鼠标事件会继续工作。

当turtle窗口打开时，首先会询问turtle.numinput()，但随后其他关键事件会正常工作。在我按下所需的键更改笔宽后，其他键事件停止工作。

我尝试稍微更改一下序列，甚至将代码的宽度部分复制到基于Turtle的另一个python文件中进行检查。我在那里也遇到了同样的问题。

我不知道是什么原因造成的，真的很感谢你的帮助

import turtle, random

wn = turtle.Screen()
wn.screensize(600, 600)

paint = turtle.Turtle('turtle')
colors = ['Red', 'Yellow', 'Green', 'Blue']
paint.width(turtle.numinput('width', 'Type line size (in numbers): '))
paint.speed(0)

# Arrow-Keys control function
def up():
    paint.setheading(90)
    paint.forward(100)

def down():
    paint.setheading(270)
    paint.forward(100)

def left():
    paint.setheading(180)
    paint.forward(100)

def right():
    paint.setheading(0)
    paint.forward(100)

# Color change
def colorChange():
    paint.color(random.choice(colors))

# Size change
def size():
    paint.width(turtle.numinput('width', 'Type line size (in numbers): '))

# Mouse Control (Clear + Drag) function
def clearScreen(x, y):
    paint.clear()

def dragging(x, y):
    paint.ondrag(None)
    paint.setheading(paint.towards(x, y))
    paint.goto(x, y)
    paint.ondrag(dragging)

# Shapes with random size
def square():
    for i in range(4):
        paint.forward(50)
        paint.left(90)

def circle():
    paint.circle(random.randrange(50, 100))

def rectangle():
    for i in range(2):
        paint.forward(50)
        paint.left(90)
        paint.forward(100)
        paint.left(90)

turtle.listen()

# Key-events

turtle.onkey(up, 'Up')
turtle.onkey(down, 'Down')
turtle.onkey(left, 'Left')
turtle.onkey(right, 'Right')

turtle.onkey(size, 'q')

turtle.onkey(colorChange, 'c')

# Mouse-events
turtle.onscreenclick(clearScreen, 3)
paint.ondrag(dragging)

# Shape-events
turtle.onkey(square, 's')
turtle.onkey(circle, 'o')
turtle.onkey(rectangle, 'r')

turtle.mainloop()

Answer 1

对numinput() (和textinput())的调用撤消了listen()所做的事情，因为弹出的输入窗口必须成为活动的侦听器。修复方法是在每次numinput() (和textinput())调用之后重做listen()调用。

下面是我使用此修复和一些样式调整对您的代码所做的修改：

from turtle import Screen, Turtle
from random import choice, randrange

COLORS = ['Red', 'Yellow', 'Green', 'Blue']

# Arrow-Keys control function
def up():
    paint.setheading(90)
    paint.forward(100)

def down():
    paint.setheading(270)
    paint.forward(100)

def left():
    paint.setheading(180)
    paint.forward(100)

def right():
    paint.setheading(0)
    paint.forward(100)

# Color change
def colorChange():
    paint.color(choice(COLORS))

# Size change
def size():
    paint.width(screen.numinput("width", "Type line size (in numbers):"))
    screen.listen()

# Mouse Control (Clear + Drag) function
def clearScreen(x, y):
    paint.clear()

def dragging(x, y):
    paint.ondrag(None)
    paint.setheading(paint.towards(x, y))
    paint.goto(x, y)
    paint.ondrag(dragging)

# Shapes with random size
def square():
    for _ in range(4):
        paint.forward(50)
        paint.left(90)

def circle():
    paint.circle(randrange(50, 100))

def rectangle():
    for _ in range(2):
        paint.forward(50)
        paint.left(90)
        paint.forward(100)
        paint.left(90)

screen = Screen()
screen.screensize(600, 600)

paint = Turtle('turtle')
paint.width(screen.numinput("width", "Type line size (in numbers):"))
paint.speed('fastest')

# Key-events

screen.onkey(up, 'Up')
screen.onkey(down, 'Down')
screen.onkey(left, 'Left')
screen.onkey(right, 'Right')

screen.onkey(size, 'q')
screen.onkey(colorChange, 'c')

# Shape-events
screen.onkey(square, 's')
screen.onkey(circle, 'o')
screen.onkey(rectangle, 'r')

screen.listen()

# Mouse-events
screen.onclick(clearScreen, 3)
paint.ondrag(dragging)

screen.mainloop()

Answer 2

您可能希望用普通的input()替换turtle.numinput()，它接受来自终端的输入，而不是来自实际模块的输入，这允许所有按键操作照常发生