使用 kivymd 和 python 在新屏幕中/上创建扩展面板

Answer 1

花了一段时间，但在帮助下我终于明白了。这是我认为代码#Comments# 中的一些关键注释的示例。

希望这可以帮助某人。

from kivymd.app import MDApp
from kivy.lang import Builder
from kivymd.uix.boxlayout import MDBoxLayout
from kivymd.uix.expansionpanel import MDExpansionPanel, MDExpansionPanelOneLine

KV = '''

#THE CONTENT GOES ABOVE EVERYTHING ELSE EVEN THE 1ST SCREEN.#
#IT IS REFERENCED LATER IN WHICH EVER SCREEN IT IS TO APPEAR USING MDGridLayout AND A def LATER ON#

#It should also always have these angle brackets <>#

<Content>
    size_hint_y: None
    height: self.minimum_height
    orientation: 'vertical'

    OneLineIconListItem:
        text: 'Dark theme'
        on_release:app.theme_changer2()
        divider: None
        IconLeftWidget:
            icon: 'weather-night'
            on_release:app.theme_changer2()

    OneLineIconListItem:
        text: 'Light theme'
        on_release:app.theme_changer()
        divider: None
        IconLeftWidget:
            icon: 'white-balance-sunny'
            on_release:app.theme_changer()

<Content2>
    size_hint_y: None
    height: self.minimum_height
    orientation: 'vertical'

    OneLineIconListItem:
        text: 'I try to explain what i think are key points to note'
        on_release:app.theme_changer2()
        divider: None
        IconLeftWidget:
            icon: 'weather-night'
            on_release:app.theme_changer2()

    OneLineIconListItem:
        text: 'Hope this helps someone else'
        on_release:app.theme_changer()
        divider: None
        IconLeftWidget:
            icon: 'white-balance-sunny'
            on_release:app.theme_changer()

MDScreen:

    MDNavigationLayout:

        ScreenManager:
            id: manager

            MDScreen:
                name: 'Home'

                #The location of this MDGridLayout shows it appears in the 1st screen.#

                MDGridLayout:
                    cols: 1
                    adaptive_height: True

                    #This id is used to reference what content goes to which expansion panel#

                    id: box2

                MDRaisedButton:
                    pos_hint: {"center_x": 0.5, "center_y": 0.5}
                    text: "PRESS ME"
                    on_release: manager.current = 'Home2'

            MDScreen:
                name: 'Home2'

                MDBoxLayout:
                    orientation: "vertical"

                    MDToolbar:
                        id: mdt_color
                        elevation: 10

                    ScrollView:
                        divider: 'None'

                        #The location of this MDGridLayout shows it appears in the 2nd screen.#

                        MDGridLayout:
                            cols: 1
                            adaptive_height: True
                            id: box

                MDIconButton:
                    pos_hint: {"center_x": 0.05, "center_y": 0.945}
                    icon: "keyboard-backspace"
                    on_release: manager.current = 'Home'

'''


# Every expansion panel should have a class corresponding to it's name e.g.#


class Content(MDBoxLayout):
    pass


# The class name is referenced in the contents= section below#


class Content2(MDBoxLayout):
    pass


class MainApp(MDApp):
    def theme_changer(self):
        self.theme_cls.theme_style = "Light"
        self.root.ids.mdt_color.md_bg_color = [1, 1, 1, 1]

    def theme_changer2(self):
        self.theme_cls.theme_style = "Dark"
        self.root.ids.mdt_color.md_bg_color = [0, 0, 0, 1]

    def build(self):
        return Builder.load_string(KV)

    def on_start(self):

        # Here you see the id box used#

        self.root.ids.box.add_widget(
            MDExpansionPanel(
                icon="theme-light-dark",

                # Here the content name Content is referenced in content=#

                content=Content(),
                panel_cls=MDExpansionPanelOneLine(
                    text="Theme",
                )
            )
        )

        # Here you see the id box2 used#

        self.root.ids.box2.add_widget(
            MDExpansionPanel(
                icon="theme-light-dark",

                # Here the content name Content2 is referenced in content=#

                content=Content2(),
                panel_cls=MDExpansionPanelOneLine(
                    text="Read the code #comments# for details",
                )
            )
        )


ma = MainApp()
ma.run()