具有两个屏幕的简单Kivy代码

Question

Here is a simple code with two screens:

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen

Builder.load_string("""
<MenuScreen>:
    BoxLayout:
        Button:
            text: 'ONE'
            on_release: root.manager.current = 'main'
        Button:
            text: 'TWO'
            on_release: root.manager.current = 'main'
<MainScreen>:
    Button:
        on_release: root.manager.current = 'menu'
""")

class MenuScreen(Screen):
    pass
class MainScreen(Screen):
    pass
class ScreenManager(ScreenManager):
    pass

sm = ScreenManager()
sm.add_widget(MenuScreen(name='menu'))
sm.add_widget(MainScreen(name='main'))

class TestApp(App):
    def build(self):
        return sm
if __name__ == '__main__':
    TestApp().run()

I need the following:

• If I click on the "ONE" button (in MenuScreen), should appear the MainScreen with a button that has the text "one" (for example)

• If I click on the "TWO" button (in MenuScreen), should appear the MainScreen with a button that has the text "two"

How can I do this?

PS Sorry for my bad English

Answer 1

Your code is really messy; I've changed it so it is more readable, and split into two files:

test.kv:

MyScreenManager:

    MenuScreen:
        id: menu
    MainScreen:
        id: main

<MenuScreen>:
    name: 'menu'

    BoxLayout:
        Button:
            text: 'ONE'
            on_release: root.switch_screen('one')

        Button:
            text: 'TWO'
            on_release: root.switch_screen('two')

<MainScreen>:
    name: 'main'

    Button:
        id: button
        on_release: root.manager.current = 'menu'

main.py:

from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen

objects = {}


class MyScreenManager(ScreenManager):
    pass


class MenuScreen(Screen):
    def switch_screen(self, text):
        objects['manager'].current = 'main'
        objects['main_button'].text = text


class MainScreen(Screen):
    pass


class TestApp(App):
    def build(self):
        objects['manager'] = self.root
        objects['main_button'] = self.root.ids.main.ids.button

if __name__ == '__main__':
    TestApp().run()