CODEWITHSUNDEEP
pythonturtle-graphics
macabeus
macabeus

Reputation: 4592

How can I pass arguments inside that method?

I'm using the library turtle. It has the onkey command, as specified:

turtle.onkeypress(fun, key=None)
Parameters:
fun – a function with no arguments or None
key – a string: key (e.g. “a”) or key-symbol (e.g. “space”)

However, I need to pass an argument. Was there any way to do this?

My code:

menuInitial.py

class MenuInitial(menu.Menu):
        [...]
    def itemInput(self):
        turtle.Screen().onkey(menu.Menu.itemUp(self), "Up")
        turtle.Screen().listen()

menu.py

class Menu(drawingGeometric.rectangle):
    [...]
    def itemUp(self):
        self.turtle.left(90)
        position.position.forwardWithoutPen(self, 16)
        self.turtle.right(90)

As can be seen, the "MenuInitial" class is heir to the "Menu". I'm learning object orientation.

Upvotes: 0

Views: 2259

Answers (1)

dano
dano

Reputation: 94951

It looks like you should just do this:

class MenuInitial(menu.Menu):
        [...]
    def itemInput(self):
        turtle.Screen().onkey(self.itemUp, "Up")
        turtle.Screen().listen()

Because you're passing itemUp as a bound instance method (self.itemUp) to onkey instead of as an unbound method (menu.Menu.itemUp), self will automatically be passed as the first argument. You can do this because MenuInitial is a child of Menu, so they share the same internal state.

If for some reason you did need to pass another argument to itemUp, you could use functools.partial:

from functools import partial

[...]

    def itemInput(self):
        func = partial(self.itemUp, "some_argument")
        turtle.Screen().onkey(func, "Up")
        turtle.Screen().listen()

Then you could have this:

class Menu(drawingGeometric.rectangle):
    [...]
    def itemUp(self, argument):
        print(argument) # This will print "some_argument"
        self.turtle.left(90)
        position.position.forwardWithoutPen(self, 16)
        self.turtle.right(90)

Upvotes: 2

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