MutablePreferences

Artifact: androidx.datastore:datastore-preferences-core

Added in 1.0.0

Kotlin |Java

Cmn
```
class MutablePreferences : Preferences
```

kotlin.Any
↳	androidx.datastore.preferences.core.Preferences
	↳	androidx.datastore.preferences.core.MutablePreferences

Mutable version of Preferences. Allows for creating Preferences with different key-value pairs.

Summary

Public functions
`open Map<Preferences.Key<*>, Any>`	`asMap()` Retrieve a map of all key preference pairs.	Cmn
`Unit`	`clear()`	Cmn
`open operator Boolean`	`<T : Any?> contains(key: Preferences.Key<T>)` Returns true if this Preferences contains the specified key.	Cmn
`open operator Boolean`	`equals(other: Any?)`	Cmn
`open operator T?`	`<T : Any?> get(key: Preferences.Key<T>)` Get a preference with a key.	Cmn
`open Int`	`hashCode()`	Cmn
`operator Unit`	`minusAssign(key: Preferences.Key<*>)` Removes the preference with the given key from this MutablePreferences.	Cmn
`operator Unit`	`plusAssign(pair: Preferences.Pair<*>)` Appends or replaces all `pair` to this MutablePreferences.	Cmn
`operator Unit`	`plusAssign(prefs: Preferences)` Appends or replaces all pairs from `prefs` to this MutablePreferences.	Cmn
`Unit`	`putAll(vararg pairs: Preferences.Pair<*>)` Appends or replaces all `pairs` to this MutablePreferences.	Cmn
`T`	`<T : Any?> remove(key: Preferences.Key<T>)` Remove a preferences from this MutablePreferences.	Cmn
`operator Unit`	`<T : Any?> set(key: Preferences.Key<T>, value: T)` Set a key value pair in MutablePreferences.	Cmn
`open String`	`toString()` For better debugging.	Cmn

Inherited functions

From androidx.datastore.preferences.core.Preferences

`MutablePreferences`	`toMutablePreferences()` Gets a mutable copy of Preferences which contains all the preferences in this Preferences.	Cmn
`Preferences`	`toPreferences()` Gets a read-only copy of Preferences which contains all the preferences in this Preferences.	Cmn

Public functions

asMap

Cmn

open fun asMap(): Map<Preferences.Key<*>, Any>

Retrieve a map of all key preference pairs. The returned map is unmodifiable, and attempts to mutate it will throw runtime exceptions.

Returns
`Map<Preferences.Key<*>, Any>`	a map containing all the preferences in this Preferences

clear

Cmn

Added in 1.0.0

fun clear(): Unit

contains

Cmn

open operator fun <T : Any?> contains(key: Preferences.Key<T>): Boolean

Returns true if this Preferences contains the specified key.

Parameters
`key: Preferences.Key<T>`	the key to check for

equals

Cmn

open operator fun equals(other: Any?): Boolean

get

Cmn

open operator fun <T : Any?> get(key: Preferences.Key<T>): T?

Get a preference with a key. If the key is not set, returns null.

If T is Set, this returns an unmodifiable set which will throw a runtime exception when mutated. Do not try to mutate the returned set.

Use MutablePreferences.set to change the value of a preference (inside a DataStore

.edit block).

Parameters
`<T : Any?>`	the type of the preference
`key: Preferences.Key<T>`	the key for the preference

Throws
`kotlin.ClassCastException`	if there is something stored with the same name as `key` but it cannot be cast to T

hashCode

Cmn

open fun hashCode(): Int

minusAssign

Cmn

Added in 1.0.0

operator fun minusAssign(key: Preferences.Key<*>): Unit

Removes the preference with the given key from this MutablePreferences. If this Preferences does not contain the key, this is a no-op.

Example usage: mutablePrefs -= COUNTER_KEY

Parameters
`key: Preferences.Key<*>`	the key to remove from this MutablePreferences

plusAssign

Cmn

Added in 1.0.0

operator fun plusAssign(pair: Preferences.Pair<*>): Unit

Appends or replaces all pair to this MutablePreferences.

Example usage: mutablePrefs += COUNTER_KEY to 100

Parameters
`pair: Preferences.Pair<*>`	the Preference.Pair to add to this MutablePreferences

plusAssign

Cmn

Added in 1.0.0

operator fun plusAssign(prefs: Preferences): Unit

Appends or replaces all pairs from prefs to this MutablePreferences. Keys in prefs will overwrite keys in this Preferences.

Example usage: mutablePrefs += preferencesOf(COUNTER_KEY to 100, NAME to "abcdef")

Parameters
`prefs: Preferences`	Preferences to append to this MutablePreferences

putAll

Cmn

Added in 1.0.0

fun putAll(vararg pairs: Preferences.Pair<*>): Unit

Appends or replaces all pairs to this MutablePreferences.

Parameters
`vararg pairs: Preferences.Pair<*>`	the pairs to append to this MutablePreferences

remove

Cmn

Added in 1.0.0

fun <T : Any?> remove(key: Preferences.Key<T>): T

Remove a preferences from this MutablePreferences.

Parameters
`key: Preferences.Key<T>`	the key to remove this MutablePreferences

Returns
`T`	the original value of this preference key.

set

Cmn

Added in 1.0.0

operator fun <T : Any?> set(key: Preferences.Key<T>, value: T): Unit

Set a key value pair in MutablePreferences.

Example usage: val COUNTER_KEY = intPreferencesKey("counter")

// Once edit completes successfully, preferenceStore will contain the incremented counter. preferenceStore.edit { prefs: MutablePreferences -> prefs\[COUNTER_KEY\] = prefs\[COUNTER_KEY\] :? 0 + 1 }

Parameters
`key: Preferences.Key<T>`	the preference to set
`value: T`	the value to set the preference to

toString

Cmn

open fun toString(): String

For better debugging.