Reputation: 907
I didn't want to use the .kv
language. So my problem occurs when trying to run a function when I press a button.
I found these question which had the same problem so I adopted the code, for the on_press method, from them:
kivy python passing parameters to fuction with button click
Python, Kivy, “AssertionError: None is not callable” Error on function call by button
The Error
File "kivy\_event.pyx", line 703, in kivy._event.EventDispatcher.dispatch
File "kivy\_event.pyx", line 1214, in kivy._event.EventObservers.dispatch
File "kivy\_event.pyx", line 1138, in kivy._event.EventObservers._dispatch
File "C:\Users\schup\PycharmProjects\Workspace\kivy_app_go\Surface.py", line 28, in <lambda>
btnHvH = Button(text="Human vs Human", size_hint=(0.35, 0.15), on_release=lambda *args: self.HelperMethodsInst.switch_screen(goal_screen="go_screen", Screenmanager=WindowManager.get_ScreenManager, *args))
TypeError: switch_screen() got multiple values for argument 'Screenmanager'
Surface.py:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy_app_go.Control import HelperMethods
from kivy.properties import ObjectProperty
from kivy.graphics import Rectangle, Color, Line
from kivy.uix.label import Label
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.core.window import Window
from kivy.uix.screenmanager import FadeTransition
from functools import partial
class MenuScreen(Screen):
def __init__(self, **kwargs):
super(Screen, self).__init__(**kwargs)
self.ScreenSize = Window.size
self.HelperMethodsInst = HelperMethods()
lytmain = FloatLayout(size=self.ScreenSize)
lytbutton = BoxLayout(pos_hint={"y": 0.1, "x": 0.15}, size_hint=(2, 0.6), orientation='vertical', size=self.ScreenSize)
lblHeadline = Label(text="Choose your Go Mode", font_size=40, pos_hint={"y": 0.8, "x": 0.325},
size_hint=(0.35, 0.15))
btnHvH = Button(text="Human vs Human", size_hint=(0.35, 0.15), on_release=lambda *args: self.HelperMethodsInst.switch_screen(goal_screen="go_screen", Screenmanager=WindowManager.get_ScreenManager, *args))
btnHvB = Button(text="Human vs Bot", size_hint=(0.35, 0.15), on_release=lambda *args: self.HelperMethodsInst.switch_screen(goal_screen="go_screen", Screenmanager=WindowManager.get_ScreenManager, *args))
btnBvB = Button(text="Bot vs Bot", size_hint=(0.35, 0.15), on_release=lambda *args: self.HelperMethodsInst.switch_screen(goal_screen="go_screen", Screenmanager=WindowManager.get_ScreenManager, *args))
self.add_widget(lytmain)
lytmain.add_widget(lblHeadline)
lytmain.add_widget(lytbutton)
lytbutton.add_widget(btnHvH)
lytbutton.add_widget(btnHvB)
lytbutton.add_widget(btnBvB)
class GoScreen(Screen):
def __init__(self, **kwargs):
super(GoScreen, self).__init__(**kwargs)
self.ScreenSize = Window.size
lytmain = FloatLayout(size=self.ScreenSize)
btnBack = Button(text="Back", size_hint=(0.25, 0.1))
self.add_widget(lytmain)
lytmain.add_widget(btnBack)
class WindowManager(ScreenManager):
def __init__(self):
self.sm = ScreenManager(transition=FadeTransition(duration=0.15))
self.sm.add_widget(MenuScreen(name="menu_screen"))
self.sm.add_widget(GoScreen(name="go_screen"))
@property
def get_ScreenManager(self):
return self.sm
class Surface(App):
def __init__(self):
super().__init__()
self.WindowManagerInst = WindowManager()
def build(self):
return self.WindowManagerInst.sm
@staticmethod
def create_Surface():
return Surface().run()
def run():
SurfaceInst = Surface()
HelperMethodsInst = HelperMethods()
Control.py:
from kivy.uix.screenmanager import ScreenManager, Screen
class HelperMethods:
def switch_screen(self, Screenmanager, goal_screen):
screenmanager = goal_screen
main.py:
from kivy_app_go.Surface import Surface
if __name__ == "__main__":
Surface.create_Surface()
I am new to kivy.
I hope someone can help ^^
Upvotes: 0
Views: 250
Reputation: 39152
You are getting the
multiple values for argument 'Screenmanager'
error because your lambda
is constructing a function with keyword arguments followed by *args
. Since positional arguments must come before keyword arguments, your *args
is treated as part of the Screenmanager=
keyword. So that keyword is passed to your switch_screen
method as
Screenmanager = WindowManager.get_ScreenManager, *args
If you need the Button
instance (which is what the *args
is) passed to your switch_screen
method, then you need to modify that method to accept it (and adjust the lambda).
You can avoid the error simply by removing the *args
from the end of the lambda
.
However, there is another problem in that same line of code. You are using WindowManager.get_ScreenManager
, but WindowManager
is a class, not an instance, and in the class file get_ScreenManager
is a property. So you need the WindowManager
instance, which you can get from the WindowManagerInst
attribute of the App
. So that line now become: (along with a call to get the running App
):
app = App.get_running_app()
btnHvH = Button(text="Human vs Human", size_hint=(0.35, 0.15), on_release=lambda *args: self.HelperMethodsInst.switch_screen(goal_screen="go_screen", Screenmanager=app.WindowManagerInst.get_ScreenManager))
Upvotes: 1