Preference

Kotlin |Java

public class Preference
extends Object implements Comparable<Preference>

java.lang.Object
↳	androidx.preference.Preference

Known direct subclasses

DialogPreference, PreferenceGroup, SeekBarPreference, TwoStatePreference

DialogPreference	A base class for `Preference`s that are dialog-based.
PreferenceGroup	A container for multiple `Preference`s.
SeekBarPreference	Preference based on android.preference.SeekBarPreference but uses support preference as a base .
TwoStatePreference	Common base class for preferences that have two selectable states, save a boolean value, and may have dependent preferences that are enabled/disabled based on the current state.

Known indirect subclasses

CheckBoxPreference, DropDownPreference, EditTextPreference, ListPreference, MultiSelectListPreference, PreferenceCategory, PreferenceScreen, SwitchPreference, SwitchPreferenceCompat

CheckBoxPreference	A `Preference` that provides checkbox widget functionality.
DropDownPreference	A `ListPreference` that presents the options in a drop down menu rather than a dialog.
EditTextPreference	A `DialogPreference` that shows a `EditText` in the dialog.
ListPreference	A `Preference` that displays a list of entries as a dialog.
MultiSelectListPreference	A `Preference` that displays a list of entries as a dialog.
PreferenceCategory	A container that is used to group similar `Preference`s.
PreferenceScreen	A top-level container that represents a settings screen.
SwitchPreference	A `Preference` that provides a two-state toggleable option.
SwitchPreferenceCompat	A `Preference` that provides a two-state toggleable option.

The basic building block that represents an individual setting displayed to a user in the preference hierarchy. This class provides the data that will be displayed to the user and has a reference to the SharedPreferences or PreferenceDataStore instance that persists the preference's values.

When specifying a preference hierarchy in XML, each element can point to a subclass of Preference, similar to the view hierarchy and layouts.

This class contains a key that that represents the key that is used to persist the value to the device. It is up to the subclass to decide how to store the value.

Developer Guides

For information about building a settings screen using the AndroidX Preference library, see Settings.

Summary

Nested classes
`class`	`Preference.BaseSavedState` A base class for managing the instance state of a `Preference`.
`interface`	`Preference.OnPreferenceChangeListener` Interface definition for a callback to be invoked when the value of this `Preference` has been changed by the user and is about to be set and/or persisted.
`interface`	`Preference.OnPreferenceClickListener` Interface definition for a callback to be invoked when a `Preference` is clicked.
`interface`	`Preference.SummaryProvider<T extends Preference>` Interface definition for a callback to be invoked when the summary of this `Preference` is requested (typically when this preference is added to the hierarchy or its value is updated).

Constants
`int`	`DEFAULT_ORDER` Specify for `setOrder(int)` if a specific order is not required.

Public constructors
`Preference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)` Perform inflation from XML and apply a class-specific base style.
`Preference(Context context, AttributeSet attrs, int defStyleAttr)` Perform inflation from XML and apply a class-specific base style.
`Preference(Context context, AttributeSet attrs)` Constructor that is called when inflating a preference from XML.
`Preference(Context context)` Constructor to create a preference.

Public methods
`boolean`	`callChangeListener(Object newValue)` Call this method after the user changes the preference, but before the internal state is set.
`int`	`compareTo(Preference another)` Compares preference objects based on order (if set), otherwise alphabetically on the titles.
`Context`	`getContext()` Returns the `Context` of this preference.
`String`	`getDependency()` Returns the key of the dependency on this preference.
`Bundle`	`getExtras()` Return the extras Bundle object associated with this preference, creating a new Bundle if there currently isn't one.
`String`	`getFragment()` Return the fragment class name associated with this preference.
`Drawable`	`getIcon()` Returns the icon of this preference.
`Intent`	`getIntent()` Return the `Intent` associated with this preference.
`String`	`getKey()` Gets the key for this preference, which is also the key used for storing values into `SharedPreferences` or `PreferenceDataStore`.
`final int`	`getLayoutResource()` Gets the layout resource that will be shown as the `View` for this preference.
`Preference.OnPreferenceChangeListener`	`getOnPreferenceChangeListener()` Returns the callback to be invoked when this preference is changed by the user (but before the internal state has been updated).
`Preference.OnPreferenceClickListener`	`getOnPreferenceClickListener()` Returns the callback to be invoked when this preference is clicked.
`int`	`getOrder()` Gets the order of this preference with respect to other preference objects on the same level.
`PreferenceGroup`	`getParent()` Returns the `PreferenceGroup` which is this preference assigned to or `null` if this preference is not assigned to any group or is a root preference.
`Set<String>`	`getPersistedStringSet(Set<String> defaultReturnValue)` Attempts to get a persisted set of Strings if this preference is persistent.
`PreferenceDataStore`	`getPreferenceDataStore()` Returns `PreferenceDataStore` used by this preference.
`PreferenceManager`	`getPreferenceManager()` Gets the `PreferenceManager` that manages this preference object's tree.
`SharedPreferences`	`getSharedPreferences()` Returns the `SharedPreferences` where this preference can read its value(s).
`boolean`	`getShouldDisableView()` Checks whether this preference should disable its view when it's action is disabled.
`CharSequence`	`getSummary()` Returns the summary of this preference.
`final SummaryProvider`	`getSummaryProvider()` Returns the `Preference.SummaryProvider` used to configure the summary of this preference.
`CharSequence`	`getTitle()` Returns the title of this preference.
`final int`	`getWidgetLayoutResource()` Gets the layout resource for the controllable widget portion of this preference.
`boolean`	`hasKey()` Checks whether this preference has a valid key.
`boolean`	`isCopyingEnabled()` Returns whether the summary of this preference can be copied to the clipboard by long pressing on the preference.
`boolean`	`isEnabled()` Checks whether this preference should be enabled in the list.
`boolean`	`isIconSpaceReserved()` Returns whether the space of this preference icon view is reserved.
`boolean`	`isPersistent()` Checks whether this preference is persistent.
`boolean`	`isSelectable()` Checks whether this preference should be selectable in the list.
`final boolean`	`isShown()` Checks whether this preference is shown to the user in the hierarchy.
`boolean`	`isSingleLineTitle()` Gets whether the title of this preference is constrained to a single line.
`final boolean`	`isVisible()` Checks whether this preference should be visible to the user.
`void`	`notifyDependencyChange(boolean disableDependents)` Notifies any listening dependents of a change that affects the dependency.
`void`	`onAttached()` Called when the preference hierarchy has been attached to the list of preferences.
`void`	`onBindViewHolder(PreferenceViewHolder holder)` Binds the created View to the data for this preference.
`void`	`onDependencyChanged(Preference dependency, boolean disableDependent)` Called when the dependency changes.
`void`	`onDetached()` Called when the preference hierarchy has been detached from the list of preferences.
`void`	`onInitializeAccessibilityNodeInfo(AccessibilityNodeInfoCompat info)` This method is deprecated. Preferences aren't views. They should not need any accessibility changes, unless the view hierarchy is customized. In this situation, please add Accessibility information in `onBindViewHolder(PreferenceViewHolder)`.
`void`	`onParentChanged(Preference parent, boolean disableChild)` Called when the implicit parent dependency changes.
`Bundle`	`peekExtras()` Return the extras Bundle object associated with this preference, returning `null` if there is not currently one.
`boolean`	`persistStringSet(Set<String> values)` Attempts to persist a set of Strings if this preference is persistent.
`void`	`restoreHierarchyState(Bundle container)` Restore this preference hierarchy's previously saved state from the given container.
`void`	`saveHierarchyState(Bundle container)` Store this preference hierarchy's frozen state into the given container.
`void`	`setCopyingEnabled(boolean enabled)` Sets whether the summary of this preference can be copied to the clipboard by long pressing on the preference.
`void`	`setDefaultValue(Object defaultValue)` Sets the default value for this preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage.
`void`	`setDependency(String dependencyKey)` Sets the key of a preference that this preference will depend on.
`void`	`setEnabled(boolean enabled)` Sets whether this preference is enabled.
`void`	`setFragment(String fragment)` Sets the class name of a fragment to be shown when this preference is clicked.
`void`	`setIcon(Drawable icon)` Sets the icon for this preference with a Drawable.
`void`	`setIcon(int iconResId)` Sets the icon for this preference with a resource ID.
`void`	`setIconSpaceReserved(boolean iconSpaceReserved)` Sets whether to reserve the space of this preference icon view when no icon is provided.
`void`	`setIntent(Intent intent)` Sets an `Intent` to be used for `Context.startActivity(Intent)` when this preference is clicked.
`void`	`setKey(String key)` Sets the key for this preference, which is used as a key to the `SharedPreferences` or `PreferenceDataStore`.
`void`	`setLayoutResource(int layoutResId)` Sets the layout resource that is inflated as the `View` to be shown for this preference.
`void`	`setOnPreferenceChangeListener(Preference.OnPreferenceChangeListener onPreferenceChangeListener)` Sets the callback to be invoked when this preference is changed by the user (but before the internal state has been updated).
`void`	`setOnPreferenceClickListener(Preference.OnPreferenceClickListener onPreferenceClickListener)` Sets the callback to be invoked when this preference is clicked.
`void`	`setOrder(int order)` Sets the order of this preference with respect to other preference objects on the same level.
`void`	`setPersistent(boolean persistent)` Sets whether this preference is persistent.
`void`	`setPreferenceDataStore(PreferenceDataStore dataStore)` Sets a `PreferenceDataStore` to be used by this preference instead of using `SharedPreferences`.
`void`	`setSelectable(boolean selectable)` Sets whether this preference is selectable.
`void`	`setShouldDisableView(boolean shouldDisableView)` Sets whether this preference should disable its view when it gets disabled.
`void`	`setSingleLineTitle(boolean singleLineTitle)` Sets whether to constrain the title of this preference to a single line instead of letting it wrap onto multiple lines.
`void`	`setSummary(CharSequence summary)` Sets the summary for this preference with a CharSequence.
`void`	`setSummary(int summaryResId)` Sets the summary for this preference with a resource ID.
`final void`	`setSummaryProvider(SummaryProvider summaryProvider)` Set a `Preference.SummaryProvider` that will be invoked whenever the summary of this preference is requested.
`void`	`setTitle(CharSequence title)` Sets the title for this preference with a CharSequence.
`void`	`setTitle(int titleResId)` Sets the title for this preference with a resource ID.
`void`	`setViewId(int viewId)` Set the ID that will be assigned to the overall View representing this preference, once bound.
`final void`	`setVisible(boolean visible)` Sets whether this preference should be visible to the user.
`void`	`setWidgetLayoutResource(int widgetLayoutResId)` Sets the layout for the controllable widget portion of this preference.
`boolean`	`shouldDisableDependents()` Checks whether this preference's dependents should currently be disabled.
`String`	`toString()`

Protected methods
`<T extends Preference> T`	`findPreferenceInHierarchy(String key)` Finds a preference in the entire hierarchy (above or below this preference) with the given key.
`boolean`	`getPersistedBoolean(boolean defaultReturnValue)` Attempts to get a persisted `Boolean` if this preference is persistent.
`float`	`getPersistedFloat(float defaultReturnValue)` Attempts to get a persisted `Float` if this preference is persistent.
`int`	`getPersistedInt(int defaultReturnValue)` Attempts to get a persisted `Integer` if this preference is persistent.
`long`	`getPersistedLong(long defaultReturnValue)` Attempts to get a persisted `Long` if this preference is persistent.
`String`	`getPersistedString(String defaultReturnValue)` Attempts to get a persisted set of Strings if this preference is persistent.
`void`	`notifyChanged()` Should be called when the data of this `Preference` has changed.
`void`	`notifyHierarchyChanged()` Should be called when a preference has been added/removed from this group, or the ordering should be re-evaluated.
`void`	`onAttachedToHierarchy(PreferenceManager preferenceManager)` Called when this preference has been attached to a preference hierarchy.
`void`	`onClick()` Processes a click on the preference.
`Object`	`onGetDefaultValue(TypedArray a, int index)` Called when a preference is being inflated and the default value attribute needs to be read.
`void`	`onPrepareForRemoval()` Called when this preference is being removed from the hierarchy.
`void`	`onRestoreInstanceState(Parcelable state)` Hook allowing a preference to re-apply a representation of its internal state that had previously been generated by `onSaveInstanceState()`.
`Parcelable`	`onSaveInstanceState()` Hook allowing a preference to generate a representation of its internal state that can later be used to create a new instance with that same state.
`void`	`onSetInitialValue(Object defaultValue)` Implement this to set the initial value of the preference.
`void`	`onSetInitialValue(boolean restorePersistedValue, Object defaultValue)` This method is deprecated. Use `onSetInitialValue(Object)` instead.
`boolean`	`persistBoolean(boolean value)` Attempts to persist a `Boolean` if this preference is persistent.
`boolean`	`persistFloat(float value)` Attempts to persist a `Float` if this preference is persistent.
`boolean`	`persistInt(int value)` Attempts to persist an `Integer` if this preference is persistent.
`boolean`	`persistLong(long value)` Attempts to persist a `Long` if this preference is persistent.
`boolean`	`persistString(String value)` Attempts to persist a `String` if this preference is persistent.
`boolean`	`shouldPersist()` Checks whether, at the given time this method is called, this preference should store/restore its value(s) into the `SharedPreferences` or into `PreferenceDataStore` if assigned.

Inherited methods

From class


        
          java.lang.Object

`Object`	`clone()`
`boolean`	`equals(Object arg0)`
`void`	`finalize()`
`final Class<?>`	`getClass()`
`int`	`hashCode()`
`final void`	`notify()`
`final void`	`notifyAll()`
`String`	`toString()`
`final void`	`wait(long arg0, int arg1)`
`final void`	`wait(long arg0)`
`final void`	`wait()`

From interface


        
          java.lang.Comparable

abstract int compareTo(Preference arg0)

Constants

DEFAULT_ORDER

public static final int DEFAULT_ORDER

Specify for setOrder(int) if a specific order is not required.

Constant Value: 2147483647 (0x7fffffff)

Public constructors

Preference

public Preference (Context context, 
                AttributeSet attrs, 
                int defStyleAttr, 
                int defStyleRes)

Perform inflation from XML and apply a class-specific base style. This constructor allows subclasses to use their own base style when they are inflating. For example, a CheckBoxPreference constructor calls this version of the super class constructor and supplies android.R.attr.checkBoxPreferenceStyle for defStyleAttr. This allows the theme's checkbox preference style to modify all of the base preference attributes as well as the CheckBoxPreference class's attributes.

Parameters
`context`	`Context`: The `Context` this is associated with, through which it can access the current theme, resources, `SharedPreferences`, etc.
`attrs`	`AttributeSet`: The attributes of the XML tag that is inflating the preference
`defStyleAttr`	`int`: An attribute in the current theme that contains a reference to a style resource that supplies default values for the view. Can be 0 to not look for defaults.
`defStyleRes`	`int`: A resource identifier of a style resource that supplies default values for the view, used only if defStyleAttr is 0 or can not be found in the theme. Can be 0 to not look for defaults.

See also:

Preference(Context, android.util.AttributeSet)

Preference

public Preference (Context context, 
                AttributeSet attrs, 
                int defStyleAttr)

Parameters
`context`	`Context`: The Context this is associated with, through which it can access the current theme, resources, `SharedPreferences`, etc.
`attrs`	`AttributeSet`: The attributes of the XML tag that is inflating the preference
`defStyleAttr`	`int`: An attribute in the current theme that contains a reference to a style resource that supplies default values for the view. Can be 0 to not look for defaults.

See also:

Preference(Context, AttributeSet)

Preference

public Preference (Context context, 
                AttributeSet attrs)

Constructor that is called when inflating a preference from XML. This is called when a preference is being constructed from an XML file, supplying attributes that were specified in the XML file. This version uses a default style of 0, so the only attribute values applied are those in the Context's Theme and the given AttributeSet.

Parameters
`context`	`Context`: The Context this is associated with, through which it can access the current theme, resources, `SharedPreferences`, etc.
`attrs`	`AttributeSet`: The attributes of the XML tag that is inflating the preference

See also:

Preference(Context, AttributeSet, int)

Preference

public Preference (Context context)

Constructor to create a preference.

Parameters
`context`	`Context`: The Context this is associated with, through which it can access the current theme, resources, `SharedPreferences`, etc.

Public methods

callChangeListener

public boolean callChangeListener (Object newValue)

Call this method after the user changes the preference, but before the internal state is set. This allows the client to ignore the user value.

Parameters
`newValue`	`Object`: The new value of this preference

Returns
`boolean`	`true` if the user value should be set as the preference value (and persisted)

compareTo

public int compareTo (Preference another)

Compares preference objects based on order (if set), otherwise alphabetically on the titles.

Parameters
`another`	`Preference`: The preference to compare to this one

Returns
`int`	0 if the same; less than 0 if this preference sorts ahead of `another`; greater than 0 if this preference sorts after `another`.

getContext

public Context getContext ()

Returns the Context of this preference. Each preference in a preference hierarchy can be from different Context (for example, if multiple activities provide preferences into a single PreferenceFragmentCompat). This Context will be used to save the preference values.

Returns
`Context`	The Context of this preference

getDependency

public String getDependency ()

Returns the key of the dependency on this preference.

Returns
`String`	The key of the dependency

See also:

setDependency(String)

getExtras

public Bundle getExtras ()

Return the extras Bundle object associated with this preference, creating a new Bundle if there currently isn't one. You can use this to get and set individual extra key/value pairs.

Returns
`Bundle`

getFragment

public String getFragment ()

Return the fragment class name associated with this preference.

Returns
`String`	The fragment class name last set via `setFragment(String)` or XML

getIcon

public Drawable getIcon ()

Returns the icon of this preference.

Returns
`Drawable`	The icon

See also:

setIcon(Drawable)

getIntent

public Intent getIntent ()

Return the Intent associated with this preference.

Returns
`Intent`	The `Intent` last set via `setIntent(Intent)` or XML

getKey

public String getKey ()

Gets the key for this preference, which is also the key used for storing values into SharedPreferences or PreferenceDataStore.

Returns
`String`	The key

getLayoutResource

public final int getLayoutResource ()

Gets the layout resource that will be shown as the View for this preference.

Returns
`int`	The layout resource ID

getOnPreferenceChangeListener

public Preference.OnPreferenceChangeListener getOnPreferenceChangeListener ()

Returns the callback to be invoked when this preference is changed by the user (but before the internal state has been updated).

Returns
`Preference.OnPreferenceChangeListener`	The callback to be invoked

getOnPreferenceClickListener

public Preference.OnPreferenceClickListener getOnPreferenceClickListener ()

Returns the callback to be invoked when this preference is clicked.

Returns
`Preference.OnPreferenceClickListener`	The callback to be invoked

getOrder

public int getOrder ()

Gets the order of this preference with respect to other preference objects on the same level.

Returns
`int`	The order of this preference

See also:

setOrder(int)

getParent

public PreferenceGroup getParent ()

Returns the PreferenceGroup which is this preference assigned to or null if this preference is not assigned to any group or is a root preference.

Returns
`PreferenceGroup`	The parent PreferenceGroup or `null` if not attached to any

getPersistedStringSet

public Set<String> getPersistedStringSet (Set<String> defaultReturnValue)

Attempts to get a persisted set of Strings if this preference is persistent.

Parameters
`defaultReturnValue`	`Set`: The default value to return if either this preference is not persistent or this preference is not present.

Returns
`Set<String>`	The value from the storage or the default return value

See also:

persistStringSet(Set)

getPreferenceDataStore

public PreferenceDataStore getPreferenceDataStore ()

Returns PreferenceDataStore used by this preference. Returns null if SharedPreferences is used instead.

By default preferences always use SharedPreferences. To make this preference to use the PreferenceDataStore you need to assign your implementation to the preference itself via setPreferenceDataStore(PreferenceDataStore) or to its PreferenceManager via PreferenceManager.setPreferenceDataStore(PreferenceDataStore).

Returns
`PreferenceDataStore`	The `PreferenceDataStore` used by this preference or `null` if none

getPreferenceManager

public PreferenceManager getPreferenceManager ()

Gets the PreferenceManager that manages this preference object's tree.

Returns
`PreferenceManager`	The `PreferenceManager`

getSharedPreferences

public SharedPreferences getSharedPreferences ()

Returns the SharedPreferences where this preference can read its value(s). Usually, it's easier to use one of the helper read methods: getPersistedBoolean(boolean), getPersistedFloat(float), getPersistedInt(int), getPersistedLong(long), getPersistedString(String).

Returns
`SharedPreferences`	The `SharedPreferences` where this preference reads its value(s). If this preference is not attached to a preference hierarchy or if a `PreferenceDataStore` has been set, this method returns `null`.

See also:

setPreferenceDataStore(PreferenceDataStore)

getShouldDisableView

public boolean getShouldDisableView ()

Checks whether this preference should disable its view when it's action is disabled.

Returns
`boolean`	`true` if it should disable the view

See also:

setShouldDisableView(boolean)

getSummary

public CharSequence getSummary ()

Returns the summary of this preference. If a Preference.SummaryProvider has been set for this preference, it will be used to provide the summary returned by this method.

Returns
`CharSequence`	The summary

See also:

getSummaryProvider

public final SummaryProvider getSummaryProvider ()

Returns the Preference.SummaryProvider used to configure the summary of this preference.

Returns
`SummaryProvider`	The `Preference.SummaryProvider` used to configure the summary of this preference, or `null` if there is no SummaryProvider set

See also:

Preference.SummaryProvider

getTitle

public CharSequence getTitle ()

Returns the title of this preference.

Returns
`CharSequence`	The title

See also:

setTitle(CharSequence)

getWidgetLayoutResource

public final int getWidgetLayoutResource ()

Gets the layout resource for the controllable widget portion of this preference.

Returns
`int`	The layout resource ID

hasKey

public boolean hasKey ()

Checks whether this preference has a valid key.

Returns
`boolean`	`true` if the key exists and is not a blank string, false otherwise

isCopyingEnabled

public boolean isCopyingEnabled ()

Returns whether the summary of this preference can be copied to the clipboard by long pressing on the preference.

Returns
`boolean`	`true` if copying is enabled, false otherwise

isEnabled

public boolean isEnabled ()

Checks whether this preference should be enabled in the list.

Returns
`boolean`	`true` if this preference is enabled, false otherwise

isIconSpaceReserved

public boolean isIconSpaceReserved ()

Returns whether the space of this preference icon view is reserved.

Returns
`boolean`	`true` if the space of this preference icon view is reserved `R.attr.iconSpaceReserved`

See also:

setIconSpaceReserved(boolean)

isPersistent

public boolean isPersistent ()

Checks whether this preference is persistent. If it is, it stores its value(s) into the persistent SharedPreferences storage by default or into PreferenceDataStore if assigned.

Returns
`boolean`	`true` if persistent

isSelectable

public boolean isSelectable ()

Checks whether this preference should be selectable in the list.

Returns
`boolean`	`true` if it is selectable, false otherwise

isShown

public final boolean isShown ()

Checks whether this preference is shown to the user in the hierarchy. For a preference to be shown in the hierarchy, it and all of its ancestors must be visible and attached to the root PreferenceScreen.

Returns
`boolean`	`true` if this preference is shown to the user in the hierarchy

isSingleLineTitle

public boolean isSingleLineTitle ()

Gets whether the title of this preference is constrained to a single line.

Returns
`boolean`	`true` if the title of this preference is constrained to a single line `R.attr.singleLineTitle`

See also:

setSingleLineTitle(boolean)

isVisible

public final boolean isVisible ()

Checks whether this preference should be visible to the user. If this preference is visible, but one or more of its ancestors are not visible, then this preference will not be shown until its ancestors are all visible.

Returns
`boolean`	`true` if this preference should be displayed

See also:

setVisible(boolean)
isShown()

notifyDependencyChange

public void notifyDependencyChange (boolean disableDependents)

Notifies any listening dependents of a change that affects the dependency.

Parameters
`disableDependents`	`boolean`: Whether this preference should disable its dependents.

onAttached

public void onAttached ()

Called when the preference hierarchy has been attached to the list of preferences. This can also be called when this preference has been attached to a group that was already attached to the list of preferences.

onBindViewHolder

public void onBindViewHolder (PreferenceViewHolder holder)

Binds the created View to the data for this preference.

This is a good place to grab references to custom Views in the layout and set properties on them.

Make sure to call through to the superclass's implementation.

Parameters
`holder`	`PreferenceViewHolder`: The ViewHolder that provides references to the views to fill in. These views will be recycled, so you should not hold a reference to them after this method returns.

onDependencyChanged

public void onDependencyChanged (Preference dependency, 
                boolean disableDependent)

Called when the dependency changes.

Parameters
`dependency`	`Preference`: The preference that this preference depends on
`disableDependent`	`boolean`: Set true to disable this preference

onDetached

public void onDetached ()

Called when the preference hierarchy has been detached from the list of preferences. This can also be called when this preference has been removed from a group that was attached to the list of preferences.

onInitializeAccessibilityNodeInfo

public void onInitializeAccessibilityNodeInfo (AccessibilityNodeInfoCompat info)

This method is deprecated.
Preferences aren't views. They should not need any accessibility changes, unless the view hierarchy is customized. In this situation, please add Accessibility information in onBindViewHolder(PreferenceViewHolder).

Initializes an AccessibilityNodeInfo with information about the View for this preference.

Parameters
`info`	`AccessibilityNodeInfoCompat`

onParentChanged

public void onParentChanged (Preference parent, 
                boolean disableChild)

Called when the implicit parent dependency changes.

Parameters
`parent`	`Preference`: The preference that this preference depends on
`disableChild`	`boolean`: Set true to disable this preference

peekExtras

public Bundle peekExtras ()

Return the extras Bundle object associated with this preference, returning null if there is not currently one.

Returns
`Bundle`

persistStringSet

public boolean persistStringSet (Set<String> values)

Attempts to persist a set of Strings if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`values`	`Set`: The values to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

getPersistedStringSet(Set)

restoreHierarchyState

public void restoreHierarchyState (Bundle container)

Restore this preference hierarchy's previously saved state from the given container.

Parameters
`container`	`Bundle`: The Bundle that holds the previously saved state

See also:

saveHierarchyState

public void saveHierarchyState (Bundle container)

Store this preference hierarchy's frozen state into the given container.

Parameters
`container`	`Bundle`: The Bundle in which to save the instance of this preference

See also:

setCopyingEnabled

public void setCopyingEnabled (boolean enabled)

Sets whether the summary of this preference can be copied to the clipboard by long pressing on the preference.

Parameters
`enabled`	`boolean`: Set true to enable copying the summary of this preference

setDefaultValue

public void setDefaultValue (Object defaultValue)

Sets the default value for this preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage.

Parameters
`defaultValue`	`Object`: The default value

setDependency

public void setDependency (String dependencyKey)

Sets the key of a preference that this preference will depend on. If that preference is not set or is off, this preference will be disabled.

Parameters
`dependencyKey`	`String`: The key of the preference that this depends on

setEnabled

public void setEnabled (boolean enabled)

Sets whether this preference is enabled. If disabled, it will not handle clicks.

Parameters
`enabled`	`boolean`: Set true to enable it

setFragment

public void setFragment (String fragment)

Sets the class name of a fragment to be shown when this preference is clicked.

Parameters
`fragment`	`String`: The class name of the fragment associated with this preference

setIcon

public void setIcon (Drawable icon)

Sets the icon for this preference with a Drawable. This icon will be placed into the ID R.id.icon within the View created by onBindViewHolder(PreferenceViewHolder).

Parameters
`icon`	`Drawable`: The optional icon for this preference

setIcon

public void setIcon (int iconResId)

Sets the icon for this preference with a resource ID.

Parameters
`iconResId`	`int`: The icon as a resource ID

See also:

setIcon(Drawable)

setIconSpaceReserved

public void setIconSpaceReserved (boolean iconSpaceReserved)

Sets whether to reserve the space of this preference icon view when no icon is provided. If set to true, the preference will be offset as if it would have the icon and thus aligned with other preferences having icons.

Parameters
`iconSpaceReserved`	`boolean`: Set `true` if the space for the icon view should be reserved `R.attr.iconSpaceReserved`

setIntent

public void setIntent (Intent intent)

Sets an Intent to be used for Context.startActivity(Intent) when this preference is clicked.

Parameters
`intent`	`Intent`: The intent associated with this preference

setKey

public void setKey (String key)

Sets the key for this preference, which is used as a key to the SharedPreferences or PreferenceDataStore. This should be unique for the package.

Parameters
`key`	`String`: The key for the preference

setLayoutResource

public void setLayoutResource (int layoutResId)

Sets the layout resource that is inflated as the View to be shown for this preference. In most cases, the default layout is sufficient for custom preference objects and only the widget layout needs to be changed.

This layout should contain a ViewGroup with ID R.id.widget_frame to be the parent of the specific widget for this preference. It should similarly contain R.id.title and R.id.summary.

It is an error to change the layout after adding the preference to a PreferenceGroup.

Parameters
`layoutResId`	`int`: The layout resource ID to be inflated and returned as a `View`

See also:

setWidgetLayoutResource(int)

setOnPreferenceChangeListener

public void setOnPreferenceChangeListener (Preference.OnPreferenceChangeListener onPreferenceChangeListener)

Sets the callback to be invoked when this preference is changed by the user (but before the internal state has been updated).

Parameters
`onPreferenceChangeListener`	`Preference.OnPreferenceChangeListener`: The callback to be invoked

setOnPreferenceClickListener

public void setOnPreferenceClickListener (Preference.OnPreferenceClickListener onPreferenceClickListener)

Sets the callback to be invoked when this preference is clicked.

Parameters
`onPreferenceClickListener`	`Preference.OnPreferenceClickListener`: The callback to be invoked

setOrder

public void setOrder (int order)

Sets the order of this preference with respect to other preference objects on the same level. If this is not specified, the default behavior is to sort alphabetically. The PreferenceGroup.setOrderingAsAdded(boolean) can be used to order preference objects based on the order they appear in the XML.

Parameters
`order`	`int`: The order for this preference. A lower value will be shown first. Use `DEFAULT_ORDER` to sort alphabetically or allow ordering from XML.

See also:

setPersistent

public void setPersistent (boolean persistent)

Sets whether this preference is persistent. When persistent, it stores its value(s) into the persistent SharedPreferences storage by default or into PreferenceDataStore if assigned.

Parameters
`persistent`	`boolean`: Set `true` if it should store its value(s) into the storage

setPreferenceDataStore

public void setPreferenceDataStore (PreferenceDataStore dataStore)

Sets a PreferenceDataStore to be used by this preference instead of using SharedPreferences.

The data store will remain assigned even if the preference is moved around the preference hierarchy. It will also override a data store propagated from the PreferenceManager that owns this preference.

Parameters
`dataStore`	`PreferenceDataStore`: The `PreferenceDataStore` to be used by this preference

See also:

PreferenceManager.setPreferenceDataStore(PreferenceDataStore)

setSelectable

public void setSelectable (boolean selectable)

Sets whether this preference is selectable.

Parameters
`selectable`	`boolean`: Set true to make it selectable

setShouldDisableView

public void setShouldDisableView (boolean shouldDisableView)

Sets whether this preference should disable its view when it gets disabled.

For example, set this and setEnabled(boolean) to false for preferences that are only displaying information and 1) should not be clickable 2) should not have the view set to the disabled state.

Parameters
`shouldDisableView`	`boolean`: Set true if this preference should disable its view when the preference is disabled.

setSingleLineTitle

public void setSingleLineTitle (boolean singleLineTitle)

Sets whether to constrain the title of this preference to a single line instead of letting it wrap onto multiple lines.

Parameters
`singleLineTitle`	`boolean`: Set `true` if the title should be constrained to one line `R.attr.singleLineTitle`

setSummary

public void setSummary (CharSequence summary)

Sets the summary for this preference with a CharSequence.

You can also use a Preference.SummaryProvider to dynamically configure the summary of this preference.

Parameters
`summary`	`CharSequence`: The summary for the preference

Throws
`IllegalStateException`	If a `Preference.SummaryProvider` has already been set.

See also:

setSummaryProvider(SummaryProvider)

setSummary

public void setSummary (int summaryResId)

Sets the summary for this preference with a resource ID.

You can also use a Preference.SummaryProvider to dynamically configure the summary of this preference.

Parameters
`summaryResId`	`int`: The summary as a resource

See also:

setSummaryProvider

public final void setSummaryProvider (SummaryProvider summaryProvider)

Set a Preference.SummaryProvider that will be invoked whenever the summary of this preference is requested. Set null to remove the existing SummaryProvider.

Parameters
`summaryProvider`	`SummaryProvider`: The `Preference.SummaryProvider` that will be invoked whenever the summary of this preference is requested

See also:

Preference.SummaryProvider

setTitle

public void setTitle (CharSequence title)

Sets the title for this preference with a CharSequence. This title will be placed into the ID R.id.title within the View bound by onBindViewHolder(PreferenceViewHolder).

Parameters
`title`	`CharSequence`: The title for this preference

setTitle

public void setTitle (int titleResId)

Sets the title for this preference with a resource ID.

Parameters
`titleResId`	`int`: The title as a resource ID

See also:

setTitle(CharSequence)

setViewId

public void setViewId (int viewId)

Set the ID that will be assigned to the overall View representing this preference, once bound.

Parameters
`viewId`	`int`

See also:

View.setId(int)

setVisible

public final void setVisible (boolean visible)

Sets whether this preference should be visible to the user. If false, it is excluded from the adapter, but can still be retrieved using PreferenceFragmentCompat.findPreference(CharSequence).

To show this preference to the user, its ancestors must also all be visible. If you make a PreferenceGroup invisible, none of its children will be shown to the user until the group is visible.

Parameters
`visible`	`boolean`: Set false if this preference should be hidden from the user `R.attr.isPreferenceVisible`

See also:

isShown()

setWidgetLayoutResource

public void setWidgetLayoutResource (int widgetLayoutResId)

Sets the layout for the controllable widget portion of this preference. This is inflated into the main layout. For example, a CheckBoxPreference would specify a custom layout (consisting of just the CheckBox) here, instead of creating its own main layout.

It is an error to change the layout after adding the preference to a PreferenceGroup.

Parameters
`widgetLayoutResId`	`int`: The layout resource ID to be inflated into the main layout

See also:

setLayoutResource(int)

shouldDisableDependents

public boolean shouldDisableDependents ()

Checks whether this preference's dependents should currently be disabled.

Returns
`boolean`	`true` if the dependents should be disabled, otherwise false

toString

public String toString ()

Returns
`String`

Protected methods

findPreferenceInHierarchy

protected T findPreferenceInHierarchy (String key)

Finds a preference in the entire hierarchy (above or below this preference) with the given key. Returns null if no preference could be found with the given key.

This only works after this preference has been attached to a hierarchy.

Parameters
`key`	`String`: The key of the preference to retrieve

Returns
`T`	The preference with the key, or `null`

See also:

PreferenceGroup.findPreference(CharSequence)

getPersistedBoolean

protected boolean getPersistedBoolean (boolean defaultReturnValue)

Attempts to get a persisted Boolean if this preference is persistent.

Parameters
`defaultReturnValue`	`boolean`: The default value to return if either this preference is not persistent or this preference is not in the SharedPreferences.

Returns
`boolean`	The value from the storage or the default return value

See also:

getPersistedFloat

protected float getPersistedFloat (float defaultReturnValue)

Attempts to get a persisted Float if this preference is persistent.

Parameters
`defaultReturnValue`	`float`: The default value to return if either this preference is not persistent or this preference is not saved.

Returns
`float`	The value from the storage or the default return value

See also:

getPersistedInt

protected int getPersistedInt (int defaultReturnValue)

Attempts to get a persisted Integer if this preference is persistent.

Parameters
`defaultReturnValue`	`int`: The default value to return if either this preference is not persistent or this preference is not in the SharedPreferences.

Returns
`int`	The value from the storage or the default return value

See also:

getPersistedLong

protected long getPersistedLong (long defaultReturnValue)

Attempts to get a persisted Long if this preference is persistent.

Parameters
`defaultReturnValue`	`long`: The default value to return if either this preference is not persistent or this preference is not in the SharedPreferences.

Returns
`long`	The value from the storage or the default return value

See also:

getPersistedString

protected String getPersistedString (String defaultReturnValue)

Attempts to get a persisted set of Strings if this preference is persistent.

Parameters
`defaultReturnValue`	`String`: The default value to return if either the preference is not persistent or the preference is not in the shared preferences.

Returns
`String`	The value from the storage or the default return value

See also:

persistString(String)

notifyChanged

protected void notifyChanged ()

Should be called when the data of this Preference has changed.

notifyHierarchyChanged

protected void notifyHierarchyChanged ()

Should be called when a preference has been added/removed from this group, or the ordering should be re-evaluated.

onAttachedToHierarchy

protected void onAttachedToHierarchy (PreferenceManager preferenceManager)

Called when this preference has been attached to a preference hierarchy. Make sure to call the super implementation.

Parameters
`preferenceManager`	`PreferenceManager`: The PreferenceManager of the hierarchy

onClick

protected void onClick ()

Processes a click on the preference. This includes saving the value to the SharedPreferences. However, the overridden method should call callChangeListener(Object) to make sure the client wants to update the preference's state with the new value.

onGetDefaultValue

protected Object onGetDefaultValue (TypedArray a, 
                int index)

Called when a preference is being inflated and the default value attribute needs to be read. Since different preference types have different value types, the subclass should get and return the default value which will be its value type.

For example, if the value type is String, the body of the method would proxy to TypedArray.getString(int).

Parameters
`a`	`TypedArray`: The set of attributes
`index`	`int`: The index of the default value attribute

Returns
`Object`	The default value of this preference type

onPrepareForRemoval

protected void onPrepareForRemoval ()

Called when this preference is being removed from the hierarchy. You should remove any references to this preference that you know about. Make sure to call through to the superclass implementation.

onRestoreInstanceState

protected void onRestoreInstanceState (Parcelable state)

Hook allowing a preference to re-apply a representation of its internal state that had previously been generated by onSaveInstanceState(). This function will never be called with a null state.

Parameters
`state`	`Parcelable`: The saved state that had previously been returned by `onSaveInstanceState()`.

See also:

onSaveInstanceState

protected Parcelable onSaveInstanceState ()

Hook allowing a preference to generate a representation of its internal state that can later be used to create a new instance with that same state. This state should only contain information that is not persistent or can be reconstructed later.

Returns
`Parcelable`	A Parcelable object containing the current dynamic state of this preference, or `null` if there is nothing interesting to save. The default implementation returns `null`.

See also:

onSetInitialValue

protected void onSetInitialValue (Object defaultValue)

Implement this to set the initial value of the preference.

If you are persisting values to SharedPreferences or a PreferenceDataStore you should restore the saved value for the preference.

If you are not persisting values, or there is no value saved for the preference, you should set the value of the preference to defaultValue.

Parameters
`defaultValue`	`Object`: The default value for the preference if set, otherwise `null`.

onSetInitialValue

protected void onSetInitialValue (boolean restorePersistedValue, 
                Object defaultValue)

This method is deprecated.
Use onSetInitialValue(Object) instead.

Implement this to set the initial value of the preference.

If restorePersistedValue is true, you should restore the preference value from the SharedPreferences. If restorePersistedValue is false, you should set the preference value to defaultValue that is given (and possibly store to SharedPreferences if shouldPersist() is true).

In case of using PreferenceDataStore, the restorePersistedValue is always true but the default value (if provided) is set.

This may not always be called. One example is if it should not persist but there is no default value given.

Parameters
`restorePersistedValue`	`boolean`: True to restore the persisted value; false to use the given `defaultValue`.
`defaultValue`	`Object`: The default value for this preference. Only use this if `restorePersistedValue` is false.

persistBoolean

protected boolean persistBoolean (boolean value)

Attempts to persist a Boolean if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`value`	`boolean`: The value to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

persistFloat

protected boolean persistFloat (float value)

Attempts to persist a Float if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`value`	`float`: The value to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

persistInt

protected boolean persistInt (int value)

Attempts to persist an Integer if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`value`	`int`: The value to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

persistLong

protected boolean persistLong (long value)

Attempts to persist a Long if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`value`	`long`: The value to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

persistString

protected boolean persistString (String value)

Attempts to persist a String if this preference is persistent.

The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.

Parameters
`value`	`String`: The value to persist

Returns
`boolean`	`true` if the preference is persistent, `false` otherwise

See also:

getPersistedString(String)

shouldPersist

protected boolean shouldPersist ()

Checks whether, at the given time this method is called, this preference should store/restore its value(s) into the SharedPreferences or into PreferenceDataStore if assigned. This, at minimum, checks whether this preference is persistent and it currently has a key. Before you save/restore from the storage, check this first.

Returns
`boolean`	`true` if it should persist the value

Preference

Developer Guides

Summary

Nested classes

Constants

Public constructors

Public methods

Protected methods

Inherited methods

Constants

DEFAULT_ORDER

Public constructors

Preference

Preference

Preference

Preference

Public methods

callChangeListener

compareTo

getContext

getDependency

getExtras

getFragment

getIcon

getIntent

getKey

getLayoutResource

getOnPreferenceChangeListener

getOnPreferenceClickListener

getOrder

getParent

getPersistedStringSet

getPreferenceDataStore

getPreferenceManager

getSharedPreferences

getShouldDisableView

getSummary

getSummaryProvider

getTitle

getWidgetLayoutResource

hasKey

isCopyingEnabled

isEnabled

isIconSpaceReserved

isPersistent

isSelectable

isShown

isSingleLineTitle

isVisible

notifyDependencyChange

onAttached

onBindViewHolder

onDependencyChanged

onDetached

onInitializeAccessibilityNodeInfo

onParentChanged

peekExtras

persistStringSet

restoreHierarchyState

saveHierarchyState

setCopyingEnabled

setDefaultValue

setDependency

setEnabled

setFragment

setIcon

setIcon

setIconSpaceReserved

setIntent

setKey

setLayoutResource

setOnPreferenceChangeListener

setOnPreferenceClickListener

setOrder

setPersistent

setPreferenceDataStore

setSelectable

setShouldDisableView

setSingleLineTitle

setSummary