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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
package mozilla.components.lib.state
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.lifecycle.Lifecycle
import androidx.lifecycle.LifecycleOwner
import androidx.lifecycle.compose.LocalLifecycleOwner
import mozilla.components.lib.state.ext.observe
import androidx.compose.runtime.State as ComposeState
/**
* Starts observing this [Store] and represents the mapped state (using [map]) via [ComposeState].
* Every time the [Store] state changes the returned [ComposeState] will be updated causing
* recomposition of every [ComposeState.value] usage.
*
* The [Store] observer will automatically be removed when this composable disposes or the current
* [LifecycleOwner] moves to the [Lifecycle.State.DESTROYED] state.
*/
@Composable
fun <S : State, A : Action, R> Store<S, A>.observeAsState(map: (S) -> R): ComposeState<R?> {
val lifecycleOwner = LocalLifecycleOwner.current
val state = remember { mutableStateOf<R?>(map(state)) }
observe(lifecycleOwner) { browserState ->
state.value = map(browserState)
}
return state
}