Package com.pranavpandey.android.dynamic.preferences

Class DynamicPreferences

java.lang.Object

com.pranavpandey.android.dynamic.preferences.DynamicPreferences

public class DynamicPreferences
extends Object

Helper class to handle shared preferences operations like saving or retrieving the values from default shared preferences.

It must be initialized once before accessing its methods.

Method Summary

Modifier and Type	Method	Description
void	delete(String key)	Remove a key from the default shared preferences.
void	delete(String preferences, String key)	Remove a key from the supplied shared preferences.
void	deleteSharedPreferences()	Delete the default shared preferences.
void	deleteSharedPreferences(String preferences)	Delete a shared preferences.
Context	getContext()	Returns the context used by this instance.
String	getDefaultSharedPreferencesName()	Get the default shared preferences name to perform other operations like backup and restore.
static DynamicPreferences	getInstance()	Retrieves the singleton instance of DynamicPreferences.
SharedPreferences	getSharedPreferences(String preferences)	Returns the SharedPreferences object for the supplied name.
static void	initializeInstance(Context context)	Initialize preferences when application starts.
static boolean	isNullKey(String key)	Checks whether the key is null as listener returns null key when it is removed (or cleared) since API 30.
boolean	load(String key, boolean value)	Retrieve a boolean preference value from the supplied shared preferences.
float	load(String key, float value)	Retrieve a float preference value from the supplied shared preferences.
int	load(String key, int value)	Retrieve an integer preference value from the supplied shared preferences.
long	load(String key, long value)	Retrieve a long preference value from the supplied shared preferences.
String	load(String key, String value)	Retrieve a String preference value from the supplied shared preferences.
boolean	load(String preferences, String key, boolean value)	Retrieve a boolean preference value from the supplied shared preferences.
float	load(String preferences, String key, float value)	Retrieve a float preference value from the supplied shared preferences.
int	load(String preferences, String key, int value)	Retrieve an integer preference value from the supplied shared preferences.
long	load(String preferences, String key, long value)	Retrieve a long preference value from the supplied shared preferences.
String	load(String preferences, String key, String value)	Retrieve a String preference value from the supplied shared preferences.
Set<String>	loadStringSet(String preferences, String key, Set<String> value)	Retrieve a Set<String> preference value from the supplied shared preferences.
Set<String>	loadStringSet(String key, Set<String> value)	Retrieve a Set<String> preference value from the supplied shared preferences.
<T> void	save(String preferences, String key, T value)	Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
<T> void	save(String preferences, String key, T value, boolean removeOnNull)	Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
<T> void	save(String key, T value)	Save a preference value in the default shared preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
<T> void	save(String key, T value, boolean removeOnNull)	Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
void	saveStringSet(String preferences, String key, Set<String> value)	Save a Set<String> in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
void	saveStringSet(String preferences, String key, Set<String> value, boolean removeOnNull)	Save a Set<String> in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
void	saveStringSet(String key, Set<String> value)	Save a Set<String> in the default preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.
void	saveStringSet(String key, Set<String> value, boolean removeOnNull)	Save a Set<String> in the default preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

initializeInstance

public static void initializeInstance(@Nullable
 Context context)

Initialize preferences when application starts.

Must be initialized once.

Parameters:

context - The context to retrieve resources.

getInstance

@NonNull
public static DynamicPreferences getInstance()

Retrieves the singleton instance of DynamicPreferences.

Must be called before accessing the public methods.

Returns:

The singleton instance of DynamicPreferences.

getContext

@NonNull
public Context getContext()

Returns the context used by this instance.

Returns:

The context to retrieve the resources.

getSharedPreferences

@NonNull
public SharedPreferences getSharedPreferences(@Nullable
 String preferences)

Returns the SharedPreferences object for the supplied name.

Use null to get the default shared preferences object.

Parameters:

preferences - The name of the shared preferences.

Returns:

The shared preferences object.

See Also:

• Context.getSharedPreferences(String, int)
• PreferenceManager.getDefaultSharedPreferences(Context)

delete

public void delete(@Nullable
 String preferences,
 @Nullable
 String key)

Remove a key from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to remove.

See Also:

• getSharedPreferences(String)
• SharedPreferences.Editor.remove(String)

delete

public void delete(@Nullable
 String key)

Remove a key from the default shared preferences.

Parameters:

key - The preference key to remove.

See Also:

• delete(String, String)

getDefaultSharedPreferencesName

@NonNull
public String getDefaultSharedPreferencesName()

Get the default shared preferences name to perform other operations like backup and restore.

Returns:

The default shared preferences name.

See Also:

• getSharedPreferences(String)

deleteSharedPreferences

public void deleteSharedPreferences(@Nullable
 String preferences)

Delete a shared preferences.

Parameters:

preferences - The preferences to be deleted.

Set null to delete the default shared preferences.

See Also:

• getSharedPreferences(String)
• SharedPreferences.Editor.clear()

deleteSharedPreferences

public void deleteSharedPreferences()

Delete the default shared preferences.

See Also:

• getSharedPreferences(String)

isNullKey

public static boolean isNullKey(@Nullable
 String key)

Checks whether the key is null as listener returns null key when it is removed (or cleared) since API 30.

Parameters:

key - The key to be checked.

Returns:

true if the key is null.

save

public <T> void save(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 T value,
 boolean removeOnNull)

Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Type Parameters:

T - The type of shared preference.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be saved or modified.

value - The value for the preference.

removeOnNull - true to remove key if the value is null.

See Also:

• getSharedPreferences(String)
• delete(String)
• SharedPreferences.Editor.putBoolean(String, boolean)
• SharedPreferences.Editor.putInt(String, int)
• SharedPreferences.Editor.putFloat(String, float)
• SharedPreferences.Editor.putLong(String, long)
• SharedPreferences.Editor.putString(String, String)

save

public <T> void save(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 T value)

Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Type Parameters:

T - The type of shared preference.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be saved or modified.

value - The value for the preference.

See Also:

• save(String, String, Object, boolean)

save

public <T> void save(@Nullable
 String key,
 @Nullable
 T value,
 boolean removeOnNull)

Save a preference value in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Type Parameters:

T - The type of shared preference.

Parameters:

key - The preference key to be saved or modified.

value - The value for the preference.

removeOnNull - true to remove key if the value is null.

See Also:

• save(String, String, Object, boolean)

save

public <T> void save(@Nullable
 String key,
 @Nullable
 T value)

Save a preference value in the default shared preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Type Parameters:

T - The type of the shared preference.

Parameters:

key - The preference key to be saved or modified.

value - The value for the preference.

See Also:

• save(String, String, Object)

saveStringSet

public void saveStringSet(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 Set<String> value,
 boolean removeOnNull)

Save a Set<String> in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be saved or modified.

value - The value for the preference.

removeOnNull - true to remove key if the value is null.

See Also:

• getSharedPreferences(String)
• delete(String)
• SharedPreferences.Editor.putStringSet(String, Set)

saveStringSet

public void saveStringSet(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 Set<String> value)

Save a Set<String> in the supplied preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be saved or modified.

value - The value for the preference.

See Also:

• saveStringSet(String, String, Set, boolean)

saveStringSet

public void saveStringSet(@Nullable
 String key,
 @Nullable
 Set<String> value,
 boolean removeOnNull)

Save a Set<String> in the default preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Parameters:

key - The preference key to be saved or modified.

value - The value for the preference.

removeOnNull - true to remove key if the value is null.

See Also:

• saveStringSet(String, String, Set, boolean)

saveStringSet

public void saveStringSet(@Nullable
 String key,
 @Nullable
 Set<String> value)

Save a Set<String> in the default preferences editor and call SharedPreferences.Editor.apply() to apply changes back from this editor.

Parameters:

key - The preference key to be saved or modified.

value - The value for the preference.

See Also:

• saveStringSet(String, String, Set)

load

public boolean load(@Nullable
 String preferences,
 @Nullable
 String key,
 boolean value)

Retrieve a boolean preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a boolean.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getBoolean(String, boolean)

load

public boolean load(@Nullable
 String key,
 boolean value)

Retrieve a boolean preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a boolean.

See Also:

• load(String, String, boolean)

load

public int load(@Nullable
 String preferences,
 @Nullable
 String key,
 int value)

Retrieve an integer preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not an integer.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getInt(String, int)

load

public int load(@Nullable
 String key,
 int value)

Retrieve an integer preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not an integer.

See Also:

• load(String, String, int)

load

public float load(@Nullable
 String preferences,
 @Nullable
 String key,
 float value)

Retrieve a float preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a float.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getFloat(String, float)

load

public float load(@Nullable
 String key,
 float value)

Retrieve a float preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a float.

See Also:

• load(String, String, float)

load

public long load(@Nullable
 String preferences,
 @Nullable
 String key,
 long value)

Retrieve a long preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a long.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getLong(String, long)

load

public long load(@Nullable
 String key,
 long value)

Retrieve a long preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a long.

See Also:

• load(String, String, long)

load

@Nullable
public String load(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 String value)

Retrieve a String preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a String.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getString(String, String)

load

@Nullable
public String load(@Nullable
 String key,
 @Nullable
 String value)

Retrieve a String preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a String.

See Also:

• load(String, String, String)

loadStringSet

@Nullable
public Set<String> loadStringSet(@Nullable
 String preferences,
 @Nullable
 String key,
 @Nullable
 Set<String> value)

Retrieve a Set<String> preference value from the supplied shared preferences.

Parameters:

preferences - The shared preferences to be used.

Set null to use the default shared preferences.

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a Set<String>.

See Also:

• getSharedPreferences(String)
• SharedPreferences.getStringSet(String, Set)

loadStringSet

@Nullable
public Set<String> loadStringSet(@Nullable
 String key,
 @Nullable
 Set<String> value)

Retrieve a Set<String> preference value from the supplied shared preferences.

Parameters:

key - The preference key to be retrieved.

value - The default value for the preference.

Returns:

Returns the preference value if it exists, or the default value.

Throws ClassCastException if there is a preference with this name that is not a Set<String>.

See Also:

• loadStringSet(String, String, Set)