Preferences
abstract class Preferences
kotlin.Any | |
↳ | androidx.datastore.preferences.core.Preferences |
Preferences and MutablePreferences are a lot like a generic Map and MutableMap keyed by the Preferences.Key class. These are intended for use with DataStore. Construct a DataStore instance using PreferenceDataStoreFactory.create.
Summary
Nested classes | |
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Key for values stored in Preferences. |
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Key Value pairs for Preferences. |
Public methods | |
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abstract Map<Preferences.Key<*>, Any> |
asMap() Retrieve a map of all key preference pairs. |
abstract operator Boolean |
contains(key: Preferences.Key<T>) Returns true if this Preferences contains the specified key. |
abstract operator T? |
get(key: Preferences.Key<T>) Get a preference with a key. |
MutablePreferences |
Gets a mutable copy of Preferences which contains all the preferences in this Preferences. |
Preferences |
Gets a read-only copy of Preferences which contains all the preferences in this Preferences. |
Public methods
asMap
abstract 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.
Return | |
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a map containing all the preferences in this Preferences |
contains
abstract operator fun <T> contains(key: Preferences.Key<T>): Boolean
Returns true if this Preferences contains the specified key.
Parameters | |
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key: Preferences.Key<T> | the key to check for |
get
abstract operator fun <T> 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 | |
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T |
the type of the preference |
key: Preferences.Key<T> | the key for the preference |
Exceptions | |
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ClassCastException |
if there is something stored with the same name as key but it cannot be cast to T |
toMutablePreferences
fun toMutablePreferences(): MutablePreferences
Gets a mutable copy of Preferences which contains all the preferences in this Preferences. This can be used to update your preferences without building a new Preferences object from scratch in DataStore.updateData.
This is similar to Map.toMutableMap.
Return | |
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a MutablePreferences with all the preferences from this Preferences |
toPreferences
fun toPreferences(): Preferences
Gets a read-only copy of Preferences which contains all the preferences in this Preferences.
This is similar to Map.toMap.
Return | |
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a copy of this Preferences |