How to scale a Image of kivy toggle button and keep its aspect ratio?

Question

Hej

I want to create my own radio button in kivy. For that I am using a template:

<myCheckBox@ToggleButton>:
    background_normal: 'gfx/cbActive.png'
    background_down: 'gfx/cbInactive.png'    
    background_disabled_down: 'gfx/cbActive.png'
    background_disabled_normal: 'gfx/cbInactive.png'

The button looks like:

When using the template at the App it can be downscaled but the downscale process does not scale it symmetrically. It looks like:

Any ideas on why the downscaling isn't symmetrical?

Answer 1

The style for Button (and ToggleButton ) uses a BorderImage to scale the background. This allows the standard button-type images to be used appropriately. But you can easily disable this behavior by setting the border property used for scaling:

<myCheckBox@ToggleButton>:
    border: 0, 0, 0, 0
    background_normal: 'gfx/cbActive.png'
    background_down: 'gfx/cbInactive.png'    
    background_disabled_down: 'gfx/cbActive.png'
    background_disabled_normal: 'gfx/cbInactive.png'