python - Kivy - 在 ModalView 中按下按钮后更改屏幕

Question

我很难弄清楚如何使用 ModalView 小部件内按钮的 on_press 属性正确更改屏幕。

按下 ModalView 中的按钮时，我希望屏幕更改为 Game1HomeScreen 类和其他 GameHomeScreen 类中定义的 game_screen_name (如下面的 NewGameButton 和 SavedGameButton 所做的那样)。此应用有多个游戏，因此我不想直接调用 Game1HomeScreen1().game_screen_name 而是希望保持其通用性，因此 game_screen_name 采用调用 NewGamePopup 的类的值。

有什么好的方法可以做到这一点？

main.py代码:

class Game1HomeScreen(Screen):
    game_screen_name = 'game1_gameboard_screen_name'


class NewGamePopup(ModalView):
    pass


class GamesApp(App):

    sm = ScreenManager()

    def show_new_game_popup(self):
        p = NewGamePopup()
        p.open()

    def prev_screen(self):
        self.sm.current = self.game_screen_name #this line does not work of course, because there is no game_screen_name variable in the NewGamePopup class.

.kv 代码:

<NewGamePopup>:
    size_hint: .5, .3
    NewGameBoxLayout:
        padding: [10,10,10,10]
        orientation: 'vertical'
        Label:
            font_name: 'fonts/playce.ttf'
            font_size: '14sp'
            markup: True
            text: '[color=#000000]Are you sure? Current game will be erased![/color]'
        Button:
            font_name: 'fonts/playce.ttf'
            font_size: '14sp'
            text: 'Confirm'
            background_normal: 'img/red_button5.png'
            background_down: 'img/red_button5.png'
            size_hint_y: None
            on_press: root.dismiss(); app.prev_screen()

<Game1HomeScreen>:
    GeneralBoxLayout:
        BannerGridLayout1:
        BodyBoxLayout:
            rows: 2
            Image:
                source: 'img/logo.png'
                size_hint: (1.0,.9)
            GridLayout:
                cols: 2
                spacing: '5dp'
                padding: '5dp'
                size_hint: (1.0,.1)
                NewGameButton:
                    id: game1
                    on_press:
                        if saved_game1.disabled == False: app.show_new_game_popup()
                        else: root.manager.current = root.game_screen_name; saved_game1.disabled = False
                SavedGameButton:
                    id: saved_game1
                    on_press: root.manager.current = root.game_screen_name;
        FooterGridLayout:
            ReturnButton:
                text: 'Return to main menu'
                on_press: root.manager.current = 'home'

Answer 1

选择游戏时将游戏屏幕名称保存在字符串属性中

from kivy.properties import StringProperty

....

class GamesApp(App):
    game_screen_name = StringProperty('')

然后您可以稍后根据需要使用 sm.current 调用。问题中的代码片段中遗漏了太多内容，无法创建工作版本；甚至连构建方法都丢失了。