Preference

const val DEFAULT_ORDER = 2147483647: Int

Specify for setOrder if a specific order is not required.

Preference(context: Context)

Constructor to create a preference.

Preference(context: Context, attrs: AttributeSet?)

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.

Preference(context: Context, attrs: AttributeSet?, defStyleAttr: Int)

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.

Preference(
    context: Context,
    attrs: AttributeSet?,
    defStyleAttr: Int,
    defStyleRes: Int
)

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.

fun callChangeListener(newValue: Any!): Boolean

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.

fun compareTo(another: Preference): Int

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

fun getContext(): Context

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.

fun getDependency(): String?

Returns the key of the dependency on this preference.

fun getExtras(): Bundle

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.

fun getFragment(): String?

Return the fragment class name associated with this preference.

fun getIcon(): Drawable?

Returns the icon of this preference.

fun getIntent(): Intent?

Return the Intent associated with this preference.

fun getKey(): String!

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

fun getLayoutResource(): Int

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

fun getOnPreferenceChangeListener(): Preference.OnPreferenceChangeListener?

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

fun getOnPreferenceClickListener(): Preference.OnPreferenceClickListener?

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

fun getOrder(): Int

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

fun getParent(): PreferenceGroup?

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.

fun getPersistedStringSet(defaultReturnValue: (Mutable)Set<String!>!): (Mutable)Set<String!>!

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

fun getPreferenceDataStore(): PreferenceDataStore?

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 or to its PreferenceManager via setPreferenceDataStore.

fun getPreferenceManager(): PreferenceManager!

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

fun getSharedPreferences(): SharedPreferences?

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

fun getShouldDisableView(): Boolean

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

fun getSummary(): CharSequence?

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

fun getSummaryProvider(): Preference.SummaryProvider?

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

fun getTitle(): CharSequence?

Returns the title of this preference.

fun getWidgetLayoutResource(): Int

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

fun hasKey(): Boolean

Checks whether this preference has a valid key.

fun isCopyingEnabled(): Boolean

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

fun isEnabled(): Boolean

Checks whether this preference should be enabled in the list.

fun isIconSpaceReserved(): Boolean

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

fun isPersistent(): Boolean

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.

fun isSelectable(): Boolean

Checks whether this preference should be selectable in the list.

fun isShown(): Boolean

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.

fun isSingleLineTitle(): Boolean

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

fun isVisible(): Boolean

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.

fun notifyDependencyChange(disableDependents: Boolean): Unit

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

fun onAttached(): Unit

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.

fun onBindViewHolder(holder: PreferenceViewHolder): Unit

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.

fun onDependencyChanged(dependency: Preference, disableDependent: Boolean): Unit

Called when the dependency changes.

fun onDetached(): Unit

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.

@CallSuper
fun onInitializeAccessibilityNodeInfo(info: AccessibilityNodeInfoCompat!): Unit

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

fun onParentChanged(parent: Preference, disableChild: Boolean): Unit

Called when the implicit parent dependency changes.

fun peekExtras(): Bundle?

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

fun persistStringSet(values: (Mutable)Set<String!>!): Boolean

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.

fun restoreHierarchyState(container: Bundle): Unit

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

fun saveHierarchyState(container: Bundle): Unit

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

fun setCopyingEnabled(enabled: Boolean): Unit

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

fun setDefaultValue(defaultValue: Any!): Unit

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.

fun setDependency(dependencyKey: String?): Unit

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.

fun setEnabled(enabled: Boolean): Unit

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

fun setFragment(fragment: String?): Unit

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

fun setIcon(icon: Drawable?): Unit

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

fun setIcon(iconResId: Int): Unit

Sets the icon for this preference with a resource ID.

fun setIconSpaceReserved(iconSpaceReserved: Boolean): Unit

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.

fun setIntent(intent: Intent?): Unit

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

fun setKey(key: String!): Unit

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

fun setLayoutResource(layoutResId: Int): Unit

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 widget_frame to be the parent of the specific widget for this preference. It should similarly contain title and summary.

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

fun setOnPreferenceChangeListener(
    onPreferenceChangeListener: Preference.OnPreferenceChangeListener?
): Unit

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

fun setOnPreferenceClickListener(
    onPreferenceClickListener: Preference.OnPreferenceClickListener?
): Unit

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

fun setOrder(order: Int): Unit

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 setOrderingAsAdded can be used to order preference objects based on the order they appear in the XML.

fun setPersistent(persistent: Boolean): Unit

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.

fun setPreferenceDataStore(dataStore: PreferenceDataStore?): Unit

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.

fun setSelectable(selectable: Boolean): Unit

Sets whether this preference is selectable.

fun setShouldDisableView(shouldDisableView: Boolean): Unit

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

For example, set this and setEnabled 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.

fun setSingleLineTitle(singleLineTitle: Boolean): Unit

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

fun setSummary(summary: CharSequence?): Unit

Sets the summary for this preference with a CharSequence.

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

fun setSummary(summaryResId: Int): Unit

Sets the summary for this preference with a resource ID.

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

fun setSummaryProvider(summaryProvider: Preference.SummaryProvider?): Unit

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

fun setTitle(title: CharSequence?): Unit

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

fun setTitle(titleResId: Int): Unit

Sets the title for this preference with a resource ID.

fun setViewId(viewId: Int): Unit

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

fun setVisible(visible: Boolean): Unit

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

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.

fun setWidgetLayoutResource(widgetLayoutResId: Int): Unit

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.

fun shouldDisableDependents(): Boolean

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

protected fun <T : Preference?> findPreferenceInHierarchy(key: String): T?

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.

protected fun getPersistedBoolean(defaultReturnValue: Boolean): Boolean

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

protected fun getPersistedFloat(defaultReturnValue: Float): Float

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

protected fun getPersistedInt(defaultReturnValue: Int): Int

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

protected fun getPersistedLong(defaultReturnValue: Long): Long

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

protected fun getPersistedString(defaultReturnValue: String!): String!

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

protected fun notifyChanged(): Unit

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

protected fun notifyHierarchyChanged(): Unit

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

protected fun onAttachedToHierarchy(preferenceManager: PreferenceManager): Unit

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

protected fun onClick(): Unit

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

protected fun onGetDefaultValue(a: TypedArray, index: Int): Any?

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 getString.

protected fun onPrepareForRemoval(): Unit

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.

protected fun onRestoreInstanceState(state: Parcelable?): Unit

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.

protected fun onSaveInstanceState(): Parcelable?

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.

protected fun onSetInitialValue(defaultValue: Any?): Unit

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.

protected fun onSetInitialValue(restorePersistedValue: Boolean, defaultValue: Any!): Unit

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.

protected fun persistBoolean(value: Boolean): Boolean

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.

protected fun persistFloat(value: Float): Boolean

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.

protected fun persistInt(value: Int): Boolean

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.

protected fun persistLong(value: Long): Boolean

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.

protected fun persistString(value: String!): Boolean

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.

protected fun shouldPersist(): Boolean

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.