Kivy Toggle Button

Question

According to the Kivy docs. "Toggle buttons can also be grouped to make radio buttons - only one button in a group can be in a ‘down’ state."

Is it possible to have 1 button using a togglebutton and change screens back and forth using the screen manager?

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.uix.boxlayout import BoxLayout

root = Builder.load_string('''

BoxLayout:
    orientation: 'vertical'

    BoxLayout:
        orientation: 'horizontal'
        size_hint: (1, .1)
        ToggleButton:
            text: "Settings"
            on_press: _screen_manager.current = 'settings'

    BoxLayout:
        orientation: 'vertical'

        ScreenManager:
            size_hint: 1, .8
            id: _screen_manager
            Screen:
                name: 'game'

            Screen:
                name: 'settings'

                BoxLayout:
                    orientation: 'vertical'
                    size_hint: (1, .1)
                    Button:
                        text: "Back"
                        on_press: _screen_manager.current = 'game'
                BoxLayout:
                    orientation: 'vertical'
 ''')


class MyApp(App):

    def build(self):
        return root

MyApp().run()

Answer 1

You can use the on_state method for this.
Try this:

from kivy.app import App
from kivy.lang import Builder


root = Builder.load_string('''

BoxLayout:
    orientation: 'vertical'

    BoxLayout:
        ToggleButton:
            text: "Settings"
            on_state: _screen_manager.current = 'settings' if self.state == 'down' else 'game'

    BoxLayout:
        orientation: 'vertical'

        ScreenManager:
            size_hint: 1, .8
            id: _screen_manager
            Screen:
                name: 'game'
                Label:
                    text: 'Game'

            Screen:
                name: 'settings'
                Label:
                    text: 'Settings' 

''')


class MyApp(App):

    def build(self):
        return root

MyApp().run()