Try this project:
ColourTransparencySlider2.aia (2.8 KB)
The button is given a colour of none, and placed inside a vertical arrangement. You vary the colour of the arrangement not the button, but the effect is as required ?
Tested in companion and compiled (android 10 and 12)
A button behaves differently and goes from colour (255) to Black (0)
You could also:
Just use an arrangement instead, and use a component click extension like this: