Sobes.tech
Junior — Middle

Can you list existing types of states in Jetpack Compose and explain their differences?

sobes.tech AI

Answer from AI

In Jetpack Compose, there are different types of state that help manage UI changes:

  • MutableState<T> — the basic state type that holds a value and notifies Compose of its changes to redraw the UI.

  • remember — a function that preserves state across recompositions within a single function call.

  • rememberSaveable — an extension of remember that saves state not only during recompositions but also across configuration changes (e.g., screen rotation) using a save mechanism.

  • StateFlow / LiveData — reactive data streams that can be used as a source of state in Compose via adapters.

Differences:

  • remember stores state only during the composition's lifetime.
  • rememberSaveable additionally preserves state when the activity is recreated.
  • MutableState is a container for a value that Compose tracks.

Example:

var count by rememberSaveable { mutableStateOf(0) }
Button(onClick = { count++ }) {
    Text("Clicked $count times")
}