SnapshotStateMap

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

An implementation of MutableMap that can be observed and snapshot. This is the result type created by androidx.compose.runtime.mutableStateMapOf.

This class closely implements the same semantics as HashMap.

Properties

firstStateRecord

override var firstStateRecord: StateRecord =
        persistentHashMapOf<K, V>().let { map ->
            val snapshot = currentSnapshot()
            StateMapStateRecord(snapshot.snapshotId, map).also {
                if (snapshot !is GlobalSnapshot) {
                    it.next =
                        StateMapStateRecord(Snapshot.PreexistingSnapshotId.toSnapshotId(), map)
                }
            }
        }

size

override val size: Int

entries

override val entries: MutableSet<MutableMap.MutableEntry<K, V>> = SnapshotMapEntrySet(this)

keys

override val keys: MutableSet<K> = SnapshotMapKeySet(this)

values

override val values: MutableCollection<V> = SnapshotMapValueSet(this)

Functions

prependStateRecord

override fun prependStateRecord(value: StateRecord)

toMap

public fun toMap(): Map<K, V>

Returns an immutable map containing all key-value pairs from the original map.

The content of the map returned will not change even if the content of the map is changed in the same snapshot. It also will be the same instance until the content is changed. It is not, however, guaranteed to be the same instance for the same content as adding and removing the same item from the this map might produce a different instance with the same content.

This operation is O(1) and does not involve a physically copying the map. It instead returns the underlying immutable map used internally to store the content of the map.

It is recommended to use toMap when using returning the value of this map from androidx.compose.runtime.snapshotFlow.

containsKey

override fun containsKey(key: K): Boolean

containsValue

override fun containsValue(value: V): Boolean

get

override fun get(key: K): V?

isEmpty

override fun isEmpty(): Boolean

toString

override fun toString(): String

clear

override fun clear(): Unit

put

override fun put(key: K, value: V): V?

putAll

override fun putAll(from: Map<out K, V>): Unit

remove

override fun remove(key: K): V?