Difference between Color.Transparent and Color.Unspecified

Question

What's the difference between Color.Transparent and Color.Unspecified in Jetpack Compose? Is one of them better for performance than the other? Which of these should be used if I don't want to see any background colour on my component at all?

OutlinedCard(colors = CardDefaults.cardColors(containerColor = Color.Transparent)) {}

or

OutlinedCard(colors = CardDefaults.cardColors(containerColor = Color.Unspecified)) {}

Answer 1

They both are transparent color. Color.Unspecified, or other Unspecified options that also exist for Size, Offset are to allow comparison using isSpecified or isUnspecified functions for corresponding instances. With Color as i recall both Color.Transparent and Color.Unspecified return same result for these 2 comparison functions.

Color.Unspecified or other ones are more suitable when you wish to check if user has entered any input while transparent defines a color choice, of course this is not set in stone you can use both.

The distinction is more apparent especially when using Offset.Unspecified or Size.Unspecified when you don't want to draw something on screen initially instead drawing something at some position or with zero size.