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PreferenceDataStore

public abstract class PreferenceDataStore
extends Object

java.lang.Object
   ↳ androidx.preference.PreferenceDataStore

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

In most cases you want to use 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.

Summary

Public constructors

PreferenceDataStore()

Public methods

boolean getBoolean(String key, boolean defValue)

Retrieves a Boolean value from the data store.

float getFloat(String key, float defValue)

Retrieves a Float value from the data store.

int getInt(String key, int defValue)

Retrieves an Integer value from the data store.

long getLong(String key, long defValue)

Retrieves a Long value from the data store.

String getString(String key, String defValue)

Retrieves a String value from the data store.

Set<String> getStringSet(String key, Set<String> defValues)

Retrieves a set of Strings from the data store.

void putBoolean(String key, boolean value)

Sets a Boolean value to the data store.

void putFloat(String key, float value)

Sets a Float value to the data store.

void putInt(String key, int value)

Sets an Integer value to the data store.

void putLong(String key, long value)

Sets a Long value to the data store.

void putString(String key, String value)

Sets a String value to the data store.

void putStringSet(String key, Set<String> values)

Sets a set of Strings to the data store.

Inherited methods

Public constructors

PreferenceDataStore

public PreferenceDataStore ()

Public methods

getBoolean

public boolean getBoolean (String key, 
                boolean defValue)

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

getFloat

public float getFloat (String key, 
                float defValue)

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

getInt

public int getInt (String key, 
                int defValue)

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

getLong

public long getLong (String key, 
                long defValue)

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

getString

public String getString (String key, 
                String defValue)

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

getStringSet

public Set<String> getStringSet (String key, 
                Set<String> defValues)

Retrieves a set of Strings from the data store.

Parameters
key String: The name of the preference to retrieve
defValues Set: Values to return if this preference does not exist in the storage
Returns
Set<String> The values from the data store or the default return values

putBoolean

public void putBoolean (String key, 
                boolean value)

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

putFloat

public void putFloat (String key, 
                float value)

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

putInt

public void putInt (String key, 
                int value)

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

putLong

public void putLong (String key, 
                long value)

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

putString

public void putString (String key, 
                String value)

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

putStringSet

public void putStringSet (String key, 
                Set<String> values)

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 Set: The set of new values for the preference