python的kivy

from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.uix.label import Label
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.checkbox import CheckBox
from kivy.uix.image import Image,AsyncImage
from kivy.uix.scatter import Scatter
class nige(App):
    def build(self):
        gl=GridLayout(cols=1)
        lable=Label(text="nige_lable")
        button=Button(text="nige_button")
        textinput=TextInput(text="nige_textinput")
        img=Image(source="kivy_learning/wu.png")
        gl.add_widget(lable)
        gl.add_widget(button)
        gl.add_widget(textinput)
        gl.add_widget(img)
        return gl
if __name__ == "__main__":
    nige().run()