morristech / uplift

A playground for elevation on Android

Uplift

     

Unbeknownst to most, elevation shadows are actually not completely inflexible. Besides setting the elevation height itself, you can tweak the shadows in clever ways to obtain subtler shadows, or simply some specific effect. This can be seen in action in the Squanchy schedule screen, which uses a custom OutlineProvider to cast shadows for the cards that look more like diffuse shadows (although they're very much still the area shadow that the Material guidelines specify, there is no custom drawing code there).

For more details, you can refer to the accompanying blogpost.

Tinting shadows (Android P+)

Starting with Android P (API 28) you can specify the colour that elevation shadows take on. You can individually tint the area and the spot shadows — although you probably want the same colour for both, most of the time. Remember, though, that shadow colours' alphas are premultiplied by a factor that is defined by the ambientShadowAlpha and spotShadowAlpha theme attributes, which are set by default to 0.039 for ambient shadows and 0.19 for spot shadows.

If you want to learn more about it, and learn how to bypass these limitations, you can refer to the dedicated blog posts, starting with the first part.

More on Uplift

You can test Uplift by downloading it from the Play Store or get the apk from the Releases tab.

Licence

See the LICENSE file. tl;dr it's Apache 2.0