lableSlider1.kv文件 

<LabelSlider>:
    orientation:‘vertical‘
    BoxLayout:
        MyLabelSlider:
            name: ‘Slider1‘
            onValue: root.onMySlider
            id:mySlider
        Label:
            text:str(mySlider.ids.slider.value)
    BoxLayout:
        orientation:‘vertical‘
        MyLabelSlider:
            name: ‘slider2‘
        MyLabelSlider:
            name: ‘slider3‘
        MyLabelSlider:
            name: ‘slider4‘
        MyLabelSlider:
            name: ‘slider5‘


<MyLabelSlider@BoxLayout>:
    name: ‘Slider‘
    onValue: lambda value: print(‘MyLabelSlider no onValue function:‘,value)
    Label:
        text:root.name
    Slider:
        id:slider
        on_value:root.onValue(self.value)


labelSlider.py文件 

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout


class LabelSlider(BoxLayout):
    def onMySlider(self, value):
        print(value)
    pass

class LabelSlider1App(App):
    def build(self):
        return LabelSlider()


if __name__ == ‘__main__‘:
    LabelSlider1App().run()

Kivy 自定义控件之（一）