Kivy - 使用.kv

Question

我试图将我的小部件创建转移到.kv而不是在我的main.py中。我怎么能仍然参考我的on_press命令？画家是另一个孩子小部件，并包含我想调用的功能，但我不确定如何从.kv中引用painter.acceptshape。

class TestingApp(App): 
    def build(self): 
    parent = FloatLayout() 

    keepbtn = Button(pos= (10,10),text='Accept Shape',size_hint=(.25, .15),font_size=14, color=(0.960784, 1, 0.980392,1), background_normal = '',\ 
     background_color= (0.0980392, 0.0980392, 0.439216,1), font_name='Exo2-Bold.otf') 

    restartbtn = Button(text='Restart',size_hint=(.2, .15),font_size=14, color=(0.960784, 1, 0.980392,1), background_normal = '',\ 
     background_color= (0.0980392, 0.0980392, 0.439216,1), font_name='Exo2-Bold.otf') 

    renderbtn = Button(text = "Render Shape", size_hint=(.2, .15),font_size=14, color=(0.960784, 1, 0.980392,1), background_normal = '',\ 
     background_color= (0.0980392, 0.0980392, 0.439216,1), font_name='Exo2-Bold.otf') 

    parent.add_widget(keepbtn) 
    parent.add_widget(restartbtn) 
    parent.add_widget(renderbtn) 

    # if free draw option 
    painter = FreeDraw() 
    keepbtn.bind(on_press=painter.acceptshape) 
    restartbtn.bind(on_press=painter.restart) 
    renderbtn.bind(on_press=painter.render) 
    parent.add_widget(painter) 

    # # if preloaded box 
    return parent 

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

KV：

<FloatLayout>: 
    canvas: 
     Rectangle: 
      source: 'background.jpg' 
      size: self.size 
      pos: self.pos 

Answer 1

这里展示了如何用一个id做一个简单的例子。

BoxLayout: 
    Button: 
     text: 'press me' 
     on_press: painter.do_something() 
    FreeDraw: 
     id: painter