属性错误：“_Screen”对象没有属性“mainloop”

Question

我正在设计一个简单的Python程序，它使用Turtle图形模块用箭头键在屏幕上画线。

import turtle

turtle.setup(400,500)                # Determine the window size
wn = turtle.Screen()                 # Get a reference to the window
wn.title("Handling keypresses!")     # Change the window title
wn.bgcolor("lightgreen")             # Set the background color
tess = turtle.Turtle()               # Create our favorite turtle

# The next four functions are our "event handlers".
def h1():
   tess.forward(30)

def h2():
   tess.left(45)

def h3():
   tess.right(45)

def h4():
    wn.bye()                        # Close down the turtle window

# These lines "wire up" keypresses to the handlers we've defined.
wn.onkey(h1, "Up")
wn.onkey(h2, "Left")
wn.onkey(h3, "Right")
wn.onkey(h4, "q")

# Now we need to tell the window to start listening for events,
# If any of the keys that we're monitoring is pressed, its
# handler will be called.
wn.listen()
wn.mainloop()

当我尝试执行它时，返回以下错误。

Traceback (most recent call last):
  File "C:\Users\Noah Huber-Feely\Desktop\PEN_Programming\Python\etchy_sketch1.py", line 32, in <module>
    wn.mainloop()
AttributeError: '_Screen' object has no attribute 'mainloop'

我使用的是 Python 2.7，之前使用 Turtle 图形没有遇到任何问题。直到现在我开始使用按键输入才出现这个问题。

在网络上搜索，我只找到了与我当前遇到的问题和模块不同的文章。

如果您需要更多信息，请告诉我。谢谢！

Answer 1

仍然是

turtle.mainloop()

，而不是

wn.mainloop()

。

我怀疑这样做的原因是因为你可以创建多个屏幕，所以仍然让

turtle

模块管理所有屏幕而不是试图使多个主循环一起工作是有意义的。