compose/androidx.compose.runtime.snapshots

Package androidx.compose.runtime.snapshots

Types

MutableSnapshot

common

open class MutableSnapshot : Snapshot

A snapshot of the values return by mutable states and other state objects.

Snapshot

common

sealed class Snapshot

A snapshot of the values return by mutable states and other state objects.

SnapshotApplyConflictException

common

class SnapshotApplyConflictException(snapshot: Snapshot) : Exception

An exception that is thrown when SnapshotApplyResult.check is called on a result of a MutableSnapshot.apply that fails to apply.

SnapshotApplyObserver

common

typealias SnapshotApplyObserver = (changed: Set<Any>, snapshot: Snapshot) -> Unit

Callback type for observing when a non-nested mutable snapshot is applied by calling MutableSnapshot.apply, modifying the visible global state of state objects. Changes to a state object outside of a snapshot are also sent to the snapshot apply observer whenever Snapshot.sendApplyNotifications is called.

The committed parameter is a collection of state objects modified in the snapshot. The snapshot parameter is the snapshot that was applied.

SnapshotApplyResult

common

sealed class SnapshotApplyResult

The result of a applying a mutable snapshot.

SnapshotReadObserver

common

typealias SnapshotReadObserver = (state: Any) -> Unit

Callback type for observing reads of state objects in a snapshot.

SnapshotStateList

common

@Stable()

class SnapshotStateList<T> : MutableList<T> , StateObject

An implementation of MutableList that can be observed and snapshot.

SnapshotStateMap

common

@Stable()

class SnapshotStateMap<K, V> : MutableMap<K, V> , StateObject

An implementation of MutableMap that can be observed and snapshot.

SnapshotStateObserver

common

class SnapshotStateObserver(onChangedExecutor: (callback: () -> Unit) -> Unit)

SnapshotWriteObserver

common

typealias SnapshotWriteObserver = (state: Any) -> Unit

Callback type for observing writes to state objects in a snapshot.

StateObject

common

interface StateObject

Interface implemented by all snapshot aware state objects.

StateRecord

common

abstract class StateRecord

Snapshot local value of a state object.

Functions

readable

common

fun <T : StateRecord> T.readable(state: StateObject): T

Return the current readable state record for the current snapshot.

fun <T : StateRecord> T.readable(state: StateObject, snapshot: Snapshot): T

Return the current readable state record for the snapshot.

snapshotFlow

common

fun <T> snapshotFlow(block: () -> T): Flow<T>

Create a Flow from observable Snapshot state.

takeMutableSnapshot

common

fun takeMutableSnapshot(readObserver: SnapshotReadObserver? = null, writeObserver: SnapshotWriteObserver? = null): MutableSnapshot

Take a snapshot of the current value of all state objects that also allows the state to be changed and later atomically applied when MutableSnapshot.apply is called.

takeSnapshot

common

fun takeSnapshot(readObserver: SnapshotReadObserver? = null): Snapshot

Take a snapshot of the current value of all state objects.

withCurrent

common

inline fun <T : StateRecord, R> T.withCurrent(block: (T) -> R): R

Provides a block with the current record, without notifying any read observers.

withMutableSnapshot

common

inline fun <R> withMutableSnapshot(block: () -> R): R

Take a MutableSnapshot and run block within it.

writable

common

inline fun <T : StateRecord, R> T.writable(state: StateObject, block: T.() -> R): R

Call block with a writable state record for the given record.

inline fun <T : StateRecord, R> T.writable(state: StateObject, snapshot: Snapshot, block: T.() -> R): R

Call block with a writable state record for snapshot of the given record.