乌龟的定义对我来说不错，但不起作用

Question

Currently, I'm trying to make a game and in the game I would like it so if the character is on top of an object, it picks it up. This is what I have so far:

import turtle
import time

default = turtle.clone()
scar = turtle.clone()

wn = turtle.Screen()
wn.setup(500,500)
wn.bgpic('TrumpTowers.gif')
wn.register_shape('default.gif')
wn.register_shape('scar.gif')
wn.register_shape('defaultscar.gif')

def drag(x, y):
    default.ondrag(None)  # disable handler inside handler

    default.goto(x, y)

    if default.distance(scar) < 40:
        default.shape('defaultscar.gif')
    elif default.shape() == 'turtle':
        default.shape('circle')

    default.ondrag(drag)

turtle.hideturtle()
default.shape('default.gif')
scar.shape('scar.gif')

default.pu()
default.left(90)
default.bk(35)

scar.pu()
scar.left(90)
scar.fd(45)
scar.speed(-1)

default.ondrag(default.goto)

Does anybody know how I would go with fixing this as it looks ok to me, but doesn't actually work!

Answer 1

I see three issues in your code. First, you're calling hideturtle() on a turtle you're not really using:

turtle.hideturtle()

This is being applied to the default turtle which shouldn't be in play. It only shows up, and gets in the way, because you do:

default = turtle.clone()
scar = turtle.clone()

Instead of:

default = turtle.Turtle()
scar = turtle.Turtle()

The speed() method does not recognize an argument of -1:

scar.speed(-1)

It will set it to a different value if the argument isn't valid.

Finally, where you're likely having the problem you're asking about, you include the definition of drag(x, y) I wrote for you but when it comes time to set a handler, you set the wrong function:

default.ondrag(default.goto)

it should be:

default.ondrag(drag)