Kivy：在Popup的屏幕之間切換

Question

我無法在kivy中切換屏幕。 從MainScreen有一個按鈕，可以打開一個Popup。 在彈出窗口內有一個按鈕，按下該按鈕時，將顯示DisplayScreen。

這是我的python代碼。

#this is MainScreen class
class MainScreen(Screen):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)

    def displayConfirmationDialog(self):
        confirmationDialog = self.MainScreenConfirmationDialog()
        confirmationDialog.setMessage()
        confirmationDialog.open()

     #this is the function of the button
    def update(self):
          self.displayConfirmationDialog()

    #this is the popup class
    class MainScreenConfirmationDialog(Popup):


        def setYesButton(self):

            screenManager.add_widget(DisplayScreen())
            self.manager.current = 'display_screen'

#this is the DisplayScreen class
class DisplayScreen(Screen):
    pass

這是我的kivy代碼

<MainScreen>:
    Button:
        text: 'UPDATE'
        on_press:root.update()

<MainScreenConfirmationDialog>:
    GridLayout:
        rows: 3
        Label:
            id: lbl_confirmation
        Button:
            id: b
            text: 'YES'
            on_press: root.setYesButton()
<DisplayScreen>:
    name: 'display_screen'
    GridLayout:
        rows: 4
        row_force_default: True
        row_default_height: 40
        Label:
            text: 'HELLO'
            id: lbl_display_name

當我運行它時，它顯示我的錯誤

    File 'main.py', line 89, in setYesButton self.manager.current = 'display_screen'
AttributeError: 'MainScreenConfirmationDialog' object has no attribute 'manager'

Answer 1

Popup小部件無權訪問screenmanager。

解

既然你可以訪問全局變量， screenManager ，更換self.manager.current = 'display_screen'與screenManager.current = 'display_screen'