Passing image object as a button background in Kivy

Question

In Kivy, is there a way to pass image object as a button background, instead of image file name?

button.background_normal property accepts only strings. I would like to customize image properties, such as allow_stretch = False.

If that succeeds, how can I specify image alignment inside a button, eg. to make it top-left aligned?

Answer 1

The source is just a property of Button and it is a string as you pointed out. You want a Widget inside a Widget, and that is the basic way Kivy works. So just add the Image as it is. A little bit of positioning would do the rest.

You have to be careful with the positioning. Make sure it is in a visible part and nothing covers it. I use a Label after the button because it has transparent Color so you can experimenting with it. For example if your positioning is wrong (try x:0 y:0) you can see the button going to the bottom-left corner in the label area.

The image I am using is the Kivy logo:

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

Builder.load_string("""
<ButtonsApp>:
    orientation: "vertical"
    Button:
        text: "B1"
        Image:
            source: 'kivy.png'
            y: self.parent.y + self.parent.height - 250
            x: self.parent.x
            size: 250, 250
            allow_stretch: True
    Label:
        text: "A label"
""")

class ButtonsApp(App, BoxLayout):
    def build(self):
        return self

if __name__ == "__main__":
    ButtonsApp().run()