python - Kivy: Top or Bottom navigation bar - Stack Overflow

admin管理员组

文章数量:1417442

For some reasons only bottom bar is shown (independently of is_mobile state). How can it be fixed?

BoxLayout:
    orientation: 'vertical'
    ActionBar:
        hidden: app.is_mobile
        size_hint_y: 0 if app.is_mobile else None
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle 1'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'
    Accordion:
        AccordionItem:
            title: '...'
            Label:
                text: '...'
        AccordionItem:
            title: '...'
            Label:
                text: '...'
    ActionBar:
        hidden: False if app.is_mobile else True
        size_hint_y: None if app.is_mobile else 0
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'

where app_mobile is calsulated as:

from kivy.utils import platform

class MainApp(App):
    is_mobile = BooleanProperty(False)

    def build(self):
        if platform in ['android', 'ios']:
            self.is_mobile = True

For some reasons only bottom bar is shown (independently of is_mobile state). How can it be fixed?

BoxLayout:
    orientation: 'vertical'
    ActionBar:
        hidden: app.is_mobile
        size_hint_y: 0 if app.is_mobile else None
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle 1'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'
    Accordion:
        AccordionItem:
            title: '...'
            Label:
                text: '...'
        AccordionItem:
            title: '...'
            Label:
                text: '...'
    ActionBar:
        hidden: False if app.is_mobile else True
        size_hint_y: None if app.is_mobile else 0
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'

where app_mobile is calsulated as:

from kivy.utils import platform

class MainApp(App):
    is_mobile = BooleanProperty(False)

    def build(self):
        if platform in ['android', 'ios']:
            self.is_mobile = True

• python
• kivy

Share Improve this question Follow asked Jan 31 at 11:39 FieryCatFieryCat 1,8992121 silver badges2828 bronze badges 2

• What do you expect to see? When is_mobile is True and when is_mobile is False. – John Anderson Commented Jan 31 at 13:41
• is_mobile is True - bottom bar is shown, and when is_mobile is False - top bar is shown – FieryCat Commented Feb 1 at 18:00

Add a comment  | 

1 Answer 1

Sorted by: Reset to default 1

The ActionBar and its children ActionButton, ... have predefined sizes in the kivy style.kv file. You can get what I believe are your desired results by working with those predefined properties. Try changing your kv to:

BoxLayout:
    orientation: 'vertical'
    ActionBar:
        hidden: app.is_mobile
        # size_hint_y: 0 if app.is_mobile else None
        opacity: 1.0 if not app.is_mobile else 0
        height: '48dp' if not app.is_mobile else 0  # `480dp` is the default height from style.kv
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle 1'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'
    Accordion:
        AccordionItem:
            title: '...'
            Label:
                text: '...'
        AccordionItem:
            title: '...'
            Label:
                text: '...'
    ActionBar:
        id: ab
        hidden: False if app.is_mobile else True
        # size_hint_y: None if app.is_mobile else 0
        opacity: 1.0 if app.is_mobile else 0
        height: '48dp' if app.is_mobile else 0  # `480dp` is the default height from style.kv
        ActionView:
            use_separator: True
            ActionPrevious:
                with_previous: True
                on_release: app.next_screen('main')
            ActionButton:
                text: 'Shuffle'
            ActionButton:
                text: 'Check'
            ActionButton:
                text: 'Next'

The height property generally makes the ActionBar visible or not. The opacity property is used to make its children visible or not, because those children also have predefined sizes and will appear even if the ActionBar has zero height.

本文标签： pythonKivy Top or Bottom navigation barStack Overflow