Kivy Not Rendering Kv File

Question

I'm trying to load a Kivy file that looks like this

#application.kv
<Grid>:
    GridLayout:
        cols:1
        size: root.width, root.height

        GridLayout:
            cols:2

            Label:
                text: "Name: "

            TextInput:
                multinline:False

            Label:
                text: "Email: "

            TextInput:
                multiline:False

        Button:
            text:"Submit"
            on_press: app.btn()

And my code looks like

class Grid(Widget):
    pass
class Application(App):

    
    def build(self):
        
        kv=Builder.load_file('application.kv')
        return kv
app=Application()
app.run()

But when I run the code I get a blank screen. Can someone tell me what I'm doing wrong?

Answer 1

Your kv file dos not define a root widget. It only define a rule that describes how to build a Grid widget (but dos not build one). You can fix that by changing:

<Grid>:

to:

Grid:

Answer 2

As John Anderson said in his answer, you the widget but not the widget.了小部件但没有小部件。 At the end of your script, just create the widget with Grid: .