PreferenceDataStore

Artifact: androidx.preference:preference

Added in 1.0.0

Kotlin |Java

abstract class PreferenceDataStore

A data store interface to be implemented and provided to the Preference 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 database, 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 is not supposed to be stored at all because they are only valid per session.

Once a put method is called it is the 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.

See also
`setPreferenceDataStore`
`setPreferenceDataStore`

Summary

Public constructors
`PreferenceDataStore()`

Public functions
`Boolean`	`getBoolean(key: String!, defValue: Boolean)` Retrieves a `Boolean` value from the data store.
`Float`	`getFloat(key: String!, defValue: Float)` Retrieves a `Float` value from the data store.
`Int`	`getInt(key: String!, defValue: Int)` Retrieves an `Integer` value from the data store.
`Long`	`getLong(key: String!, defValue: Long)` Retrieves a `Long` value from the data store.
`String?`	`getString(key: String!, defValue: String?)` Retrieves a `String` value from the data store.
`(Mutable)Set<String!>?`	`getStringSet(key: String!, defValues: (Mutable)Set<String!>?)` Retrieves a set of Strings from the data store.
`Unit`	`putBoolean(key: String!, value: Boolean)` Sets a `Boolean` value to the data store.
`Unit`	`putFloat(key: String!, value: Float)` Sets a `Float` value to the data store.
`Unit`	`putInt(key: String!, value: Int)` Sets an `Integer` value to the data store.
`Unit`	`putLong(key: String!, value: Long)` Sets a `Long` value to the data store.
`Unit`	`putString(key: String!, value: String?)` Sets a `String` value to the data store.
`Unit`	`putStringSet(key: String!, values: (Mutable)Set<String!>?)` Sets a set of `String`s to the data store.

Public constructors

PreferenceDataStore

Added in 1.0.0

PreferenceDataStore()

Public functions

getBoolean

Added in 1.0.0

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

Retrieves 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 in the storage

Returns
`Boolean`	the value from the data store or the default return value

See also
`getBoolean`

getFloat

Added in 1.0.0

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

Retrieves 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 in the storage

Returns
`Float`	The value from the data store or the default return value

See also
`putFloat`

getInt

Added in 1.0.0

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

Retrieves an Integer 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 in the storage

Returns
`Int`	The value from the data store or the default return value

See also
`putInt`

getLong

Added in 1.0.0

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

Retrieves 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 in the storage

Returns
`Long`	The value from the data store or the default return value

See also
`putLong`

getString

Added in 1.0.0

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

Retrieves 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 in the storage

Returns
`String?`	The value from the data store or the default return value

See also
`putString`

getStringSet

Added in 1.0.0

fun getStringSet(key: String!, defValues: (Mutable)Set<String!>?): (Mutable)Set<String!>?

Retrieves a set of Strings from the data store.

Parameters
`key: String!`	The name of the preference to retrieve
`defValues: (Mutable)Set<String!>?`	Values to return if this preference does not exist in the storage

Returns
`(Mutable)Set<String!>?`	The values from the data store or the default return values

See also
`putStringSet`

putBoolean

Added in 1.0.0

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

Sets 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`

putFloat

Added in 1.0.0

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

Sets 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`

putInt

Added in 1.0.0

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

Sets an Integer 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`

putLong

Added in 1.0.0

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

Sets 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`

putString

Added in 1.0.0

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

Sets 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

See also
`getString`

putStringSet

Added in 1.0.0

fun putStringSet(key: String!, values: (Mutable)Set<String!>?): Unit

Sets a set of Strings 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: (Mutable)Set<String!>?`	The set of new values for the preference

See also
`getStringSet`