Kivy 切换按钮行为

Question

我尝试在两个或多个标签（如单选按钮）之间建立切换。到目前为止，它与 ToggleButtonBehavior 一起工作以更改组之间的状态，但是当我单击所选项目时，它被取消选择并且不应该这样做。

class SelectButton(ToggleButtonBehavior, Label):
    active = BooleanProperty(False)
    def __init__(self, **kwargs):
        super(SelectButton, self).__init__(**kwargs)

        self.text='off'
        self.color=[1,0,1,1]

        self.bind(state=self.toggle)

    def toggle(self, instance, value):
        if self.state == 'down':
            self.text = 'on'
        else:
            self.text = 'off'

有没有办法获得类似单选按钮的行为？

Answer 1

有个allow_no_selection property:

This specifies whether the widgets in a group allow no selection i.e. everything to be deselected.

allow_no_selection is a BooleanProperty and defaults to True

将其设置为 False 并使用组后，一切开始按预期工作：

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.label import Label
from kivy.uix.behaviors import ToggleButtonBehavior
from kivy.properties import BooleanProperty
from kivy.lang import Builder

Builder.load_string('''
<MyWidget>:
    SelectButton:
        state: 'down'
        text: 'on'
    SelectButton
        state: 'normal'
        text: 'off'
    SelectButton
        state: 'normal'
        text: 'off'
''')

class SelectButton(ToggleButtonBehavior, Label):
    active = BooleanProperty(False)

    def __init__(self, **kwargs):
        super(SelectButton, self).__init__(**kwargs)

        self.allow_no_selection = False

        self.group = "mygroup"
        self.color=[1,0,1,1]

        self.bind(state=self.toggle)

    def toggle(self, instance, value):
        if self.state == 'down':
            self.text = 'on'
        else:
            self.text = 'off'

class MyWidget(BoxLayout):
    pass

class MyApp(App):
    def build(self):
        return MyWidget()

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

Kivy 切换按钮行为

Kivy ToggleButtonBehavior

python

kivy