Jetpack Compose Getting Light vs Dark Mode from MaterialTheme Using Material 3

Question

With Jetpack Compose, using Material 2, you can see if a theme is in light mode easily with the following

val light = MaterialTheme.colors.isLight

Using Material 3, I don't see this ability. Is there a way to do this with a Material 3 theme?

Answer 1

Found a solution. Color in Compose has a built in method luminance that returns the relative luminance as a float between 0 and 1. I wrote an extension function for ColorScheme that returns true if the luminance of the background is greater than 0.5.

@Composable
fun ColorScheme.isLight() = this.background.luminance() > 0.5

Using it as:

val isLight = MaterialTheme.colorScheme.isLight()

Now whether the system is in dark mode doesn't matter, only the theme.