How to make multi-window applications without Builder in Kivy

I want to make a program on Kivy, using several windows, but I would like to do it without the Builder, but I can not understand what needs to be entered in on_press. I tried this way:

1. on_press = root.manage.current = "name" 2. on_press = root.manager.current == "name"

But in the first option, SyntaxError: invalid syntax is eliminated, and in the second NameError: name "root" is not defined.

Here is part of the code:

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.uix.boxlayout import BoxLayout

class LenPasword(Screen):
    pass

program = ScreenManager()
program.add_widget(LenPasword(name = "lenpasword"))

class PaswordingApp(App):
    def build(self):
        boxlayout = BoxLayout(orientation = "vertical", spacing = 5, padding = [10])

        button_new_pasword = Button(text = "New Pasword",
                                    background_color = [0, 1.5, 3, 1],
                                    size_hint = [1, 0.1])

        boxlayout.add_widget(button_new_pasword)

        return boxlayout
        return program

if __name__ == "__main__":
    PaswordingApp().run()
Author: Victor VosMottor, 2020-07-28
Source

1 answers

Steps:

  • Creating windows from Screen
  • In the constructor, fill them with widgets
  • Add a code for changing the current screen for each user via self.manager.current =
  • In the application class, create ScreenManager, add your windows to it, and return ScreenManager

Try this way:

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.button import Button
from kivy.uix.boxlayout import BoxLayout


class ScreenMain(Screen):
    def __init__ (self, **kwargs):
        super().__init__(**kwargs)

        boxlayout = BoxLayout(orientation="vertical", spacing=5, padding=[10])

        button_new_pasword = Button(
            text="New Pasword",
            background_color=[0, 1.5, 3, 1],
            size_hint=[1, 0.1],
            on_press=self._on_press_button_new_pasword,
        )

        boxlayout.add_widget(button_new_pasword)
        self.add_widget(boxlayout)

    def _on_press_button_new_pasword(self, *args):
        self.manager.transition.direction = 'left'
        self.manager.current = 'lenpasword'


class LenPasword(Screen):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

        boxlayout = BoxLayout(orientation="vertical", spacing=5, padding=[10])

        button_new_pasword = Button(
            text="Return",
            background_color=[2, 1.5, 3, 1],
            size_hint=[1, 0.1],
            on_press=self._on_press_button_new_pasword,
        )

        boxlayout.add_widget(button_new_pasword)
        self.add_widget(boxlayout)

    def _on_press_button_new_pasword(self, *args):
        self.manager.transition.direction = 'right'
        self.manager.current = 'main_screen'


class PaswordingApp(App):
    def build(self):
        sm = ScreenManager()
        sm.add_widget(ScreenMain(name='main_screen'))
        sm.add_widget(LenPasword(name='lenpasword'))

        return sm

if __name__ == "__main__":
    PaswordingApp().run()
 3
Author: gil9red, 2020-07-28 12:58:20