kivy：是否可以在不同的屏幕上使用相同的选项卡式面板？

Question

im wondering if it is possible to have a Tabbed Panel permanently even though im switching between screens? Ive tried having the TabbedPanel outside the mainscreen, on a different class and so on. So far when i switch to the FirstScreen the TabbedPanel disapears.

Python:

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

class TabbedTest(TabbedPanel):
    pass
class MainScreen(Screen):
    pass
class Firstscreen(Screen):
    pass
class Secondscreen(Screen):
    pass

class myapp(App):

def build(self):
    # Create the screen manager
    sm = ScreenManager()
    sm.add_widget(MainScreen(name='main'))
    sm.add_widget(Firstscreen(name='first'))
    sm.add_widget(Secondscreen(name='second'))

    return sm

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

kv:

<TabbedTest>:
    do_default_tab: False
    TabbedPanelItem:
        text:"test"

<MainScreen>:
    BoxLayout:
        Button:
            text: 'first'
            on_press: root.manager.current = 'first'
        Button:
            text: 'second'
            on_press: root.manager.current = 'second'

<Firstscreen>:
    BoxLayout:
        Label:
            text:"first"
        Button:
            text: 'Back to main'
            on_press: root.manager.current = 'main'

<Secondscreen>:
    BoxLayout:
        Label:
            text:'second'
        Button:
            text: 'Back to main'
            on_press: root.manager.current = 'main'

Answer 1

Rather than adding the TabbedTest to each Screen , just make the TabbedTest and ScreenManager as children of the root widget of the App . One way to do this is to modify the build() method:

def build(self):
    root = FloatLayout()
    self.tabbedtest = TabbedTest(size_hint_y=0.5, pos_hint={'top': 1.0})  # later you can use self.tabbedtest to add more tabs
    root.add_widget(self.tabbedtest)

    # Create the screen manager
    sm = ScreenManager(size_hint_y=0.5, pos_hint={'y': 0})
    sm.add_widget(MainScreen(name='main'))
    sm.add_widget(Firstscreen(name='first'))
    sm.add_widget(Secondscreen(name='second'))
    root.add_widget(sm)

    return root