Added in API level 26
Deprecated in API level 29

PreferenceDataStore

Kotlin |Java

interface PreferenceDataStore

android.preference.PreferenceDataStore

A data store interface to be implemented and provided to the Preferences framework. This can be used to replace the default android.content.SharedPreferences, if needed.

In most cases you want to use android.content.SharedPreferences as it is automatically backed up and migrated to new devices. However, providing custom data store to preferences can be useful if your app stores its preferences in a local db, cloud or they are device specific like "Developer settings". It might be also useful when you want to use the preferences UI but the data are not supposed to be stored at all because they are valid per session only.

Once a put method is called it is full responsibility of the data store implementation to safely store the given values. Time expensive operations need to be done in the background to prevent from blocking the UI. You also need to have a plan on how to serialize the data in case the activity holding this object gets destroyed.

By default, all "put" methods throw UnsupportedOperationException.

Summary

Public methods
open Boolean	`getBoolean(key: String!, defValue: Boolean)` Retrieve a boolean value from the data store.
open Float	`getFloat(key: String!, defValue: Float)` Retrieve a float value from the data store.
open Int	`getInt(key: String!, defValue: Int)` Retrieve an int value from the data store.
open Long	`getLong(key: String!, defValue: Long)` Retrieve a long value from the data store.
open String?	`getString(key: String!, defValue: String?)` Retrieve a String value from the data store.
open MutableSet<String!>?	`getStringSet(key: String!, defValues: MutableSet<String!>?)` Retrieve a set of String values from the data store.
open Unit	`putBoolean(key: String!, value: Boolean)` Set a boolean value to the data store.
open Unit	`putFloat(key: String!, value: Float)` Set a float value to the data store.
open Unit	`putInt(key: String!, value: Int)` Set an int value to the data store.
open Unit	`putLong(key: String!, value: Long)` Set a long value to the data store.
open Unit	`putString(key: String!, value: String?)` Set a String value to the data store.
open Unit	`putStringSet(key: String!, values: MutableSet<String!>?)` Set a set of String value to the data store.

Public methods

getBoolean

Added in API level 26

open fun getBoolean(
    key: String!, 
    defValue: Boolean
): Boolean

Deprecated: Deprecated in Java.

Retrieve a boolean value from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValue`	Boolean: Value to return if this preference does not exist.

See Also

#getBoolean(String, boolean)

getFloat

Added in API level 26

open fun getFloat(
    key: String!, 
    defValue: Float
): Float

Deprecated: Deprecated in Java.

Retrieve a float value from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValue`	Float: Value to return if this preference does not exist.

See Also

#putFloat(String, float)

getInt

Added in API level 26

open fun getInt(
    key: String!, 
    defValue: Int
): Int

Deprecated: Deprecated in Java.

Retrieve an int value from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValue`	Int: Value to return if this preference does not exist.

See Also

#putInt(String, int)

getLong

Added in API level 26

open fun getLong(
    key: String!, 
    defValue: Long
): Long

Deprecated: Deprecated in Java.

Retrieve a long value from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValue`	Long: Value to return if this preference does not exist.

See Also

#putLong(String, long)

getString

Added in API level 26

open fun getString(
    key: String!, 
    defValue: String?
): String?

Deprecated: Deprecated in Java.

Retrieve a String value from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValue`	String?: Value to return if this preference does not exist. This value may be `null`.

Return
`String?`	This value may be `null`.

See Also

#putString(String, String)

getStringSet

Added in API level 26

open fun getStringSet(
    key: String!, 
    defValues: MutableSet<String!>?
): MutableSet<String!>?

Deprecated: Deprecated in Java.

Retrieve a set of String values from the data store.

Parameters
`key`	String!: The name of the preference to retrieve.
`defValues`	MutableSet<String!>?: Values to return if this preference does not exist. This value may be `null`.

Return
`MutableSet<String!>?`	This value may be `null`.

See Also

#putStringSet(String, Set)

putBoolean

Added in API level 26

open fun putBoolean(
    key: String!, 
    value: Boolean
): Unit

Deprecated: Deprecated in Java.

Set a boolean value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`value`	Boolean: The new value for the preference.

See Also

#getBoolean(String, boolean)

putFloat

Added in API level 26

open fun putFloat(
    key: String!, 
    value: Float
): Unit

Deprecated: Deprecated in Java.

Set a float value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`value`	Float: The new value for the preference.

See Also

#getFloat(String, float)

putInt

Added in API level 26

open fun putInt(
    key: String!, 
    value: Int
): Unit

Deprecated: Deprecated in Java.

Set an int value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`value`	Int: The new value for the preference.

See Also

#getInt(String, int)

putLong

Added in API level 26

open fun putLong(
    key: String!, 
    value: Long
): Unit

Deprecated: Deprecated in Java.

Set a long value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`value`	Long: The new value for the preference.

See Also

#getLong(String, long)

putString

Added in API level 26

open fun putString(
    key: String!, 
    value: String?
): Unit

Deprecated: Deprecated in Java.

Set a String value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`value`	String?: The new value for the preference. This value may be `null`.

See Also

#getString(String, String)

putStringSet

Added in API level 26

open fun putStringSet(
    key: String!, 
    values: MutableSet<String!>?
): Unit

Deprecated: Deprecated in Java.

Set a set of String value to the data store.

Once the value is set the data store is responsible for holding it.

Parameters
`key`	String!: The name of the preference to modify.
`values`	MutableSet<String!>?: The set of new values for the preference. This value may be `null`.

See Also

#getStringSet(String, Set)