setAlpha(0) will prevent drawing but other values will be full opacity. This is because setAlpha just overrides the color's alpha value, but we reset the color each time we draw.

Comment on attachment 8532254 [details] [diff] [review] setAlpha after setColor in ResizablePathDrawable Review of attachment 8532254 [details] [diff] [review]: ----------------------------------------------------------------- Yep. ::: mobile/android/base/widget/ResizablePathDrawable.java @@ +58,5 @@ > + // setAlpha overrides the alpha value in set color. Since we just set the color, > + // the alpha value is reset: override the alpha value with the old value. > + // > + // Note: We *should* be able to setAlpha on the Shape, rather than the Paint, but > + // this the opacity doesn't change - dunno why but probably not worth the time. nit: remove the 'the'

Updated for nits.

re comment 6: I forgot to update the alpha when updating the color.

Comment on attachment 8532576 [details] [diff] [review] setAlpha after setColor in ResizablePathDrawable Applies to parts 1 and 2. Approval Request Comment [Feature/regressing bug #]: New tablet release [User impact if declined]: We won't be able to uplift bug 1085771, which means lightweight themes will be unpolished in the new tablet release [Describe test coverage new/current, TBPL]: None [Risks and why]: We could cause issues with the alpha channels in the tab strip which, in the worst case means the tabs disappear, but generally means we'll look less polished. [String/UUID change made/needed]: None