SavedStateRegistryOwner

Artifact: androidx.savedstate:savedstate

View Source

Added in 1.0.0

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Kotlin |Java

public interface SavedStateRegistryOwner extends LifecycleOwner

Known direct subclasses

ComponentActivity, ComponentDialog, Fragment, NavBackStackEntry

ComponentActivity	Base class for activities that enables composition of higher level components.
ComponentDialog	Base class for dialogs that enables composition of higher level components.
Fragment	Static library support version of the framework's android.app.Fragment.
NavBackStackEntry	Representation of an entry in the back stack of a androidx.navigation.NavController.

Known indirect subclasses

AbstractListDetailFragment, AbstractProgressFragment, AlertDialog, AmbientModeSupport, AppCompatActivity, AppCompatDialogFragment, AppCompatDialog, BaseCarAppActivity, BaseLeanbackPreferenceFragmentCompat, BaseSupportFragment, BrandedSupportFragment, BrowseSupportFragment, CarAppActivity, DefaultProgressFragment, DetailsSupportFragment, DialogFragment, DynamicNavHostFragment, EditTextPreferenceDialogFragmentCompat, ErrorSupportFragment, FragmentActivity, GuidedStepSupportFragment, HeadersSupportFragment, LauncherActivity, LeanbackEditTextPreferenceDialogFragmentCompat, LeanbackListPreferenceDialogFragmentCompat, LeanbackPreferenceDialogFragmentCompat, LeanbackPreferenceFragmentCompat, LeanbackSettingsFragmentCompat, ListFragment, ListPreferenceDialogFragmentCompat, MediaRouteChooserDialogFragment, MediaRouteChooserDialog, MediaRouteControllerDialogFragment, MediaRouteControllerDialog, MediaRouteDiscoveryFragment, MultiSelectListPreferenceDialogFragmentCompat, NavHostFragment, OnboardingSupportFragment, PdfViewerFragment, PlaybackSupportFragment, PreferenceDialogFragmentCompat, PreferenceFragmentCompat, PreferenceHeaderFragmentCompat, RowsSupportFragment, SearchSupportFragment, VerticalGridSupportFragment, VideoSupportFragment

AbstractListDetailFragment	A fragment supports adaptive two-pane layout.
AbstractProgressFragment	The base class for Fragments that handle dynamic feature installation.
AlertDialog	A subclass of Dialog that can display one, two or three buttons.
AmbientModeSupport	This class is deprecated. Use AmbientLifecycleObserver instead.
AppCompatActivity	Base class for activities that wish to use some of the newer platform features on older Android devices.
AppCompatDialogFragment	A special version of DialogFragment which uses an AppCompatDialog in place of a platform-styled dialog.
AppCompatDialog	Base class for AppCompat themed android.app.Dialogs.
BaseCarAppActivity	Core logic for CarAppLibrary Activity interaction with a host.
BaseLeanbackPreferenceFragmentCompat	This fragment provides a preference fragment with leanback-style behavior, suitable for embedding into broader UI elements.
BaseSupportFragment	Base class for leanback Fragments.
BrandedSupportFragment	Fragment class for managing search and branding using a view that implements TitleViewAdapter.Provider.
BrowseSupportFragment	A fragment for creating Leanback browse screens.
CarAppActivity	The class representing a car app activity in the main display.
DefaultProgressFragment	The default androidx.fragment.app.Fragment to display during installation progress.
DetailsSupportFragment	A fragment for creating Leanback details screens.
DialogFragment	A fragment that displays a dialog window, floating in the foreground of its activity's window.
DynamicNavHostFragment	The NavHostFragment for dynamic features.
EditTextPreferenceDialogFragmentCompat
ErrorSupportFragment	A fragment for displaying an error indication.
FragmentActivity	Base class for activities that want to use the support-based Fragments.
GuidedStepSupportFragment	A GuidedStepSupportFragment is used to guide the user through a decision or series of decisions.
HeadersSupportFragment	An fragment containing a list of row headers.
LauncherActivity	This class handles providing the right launcher activity when running native applications and Car App Library applications.
LeanbackEditTextPreferenceDialogFragmentCompat	Implemented a dialog to input text.
LeanbackListPreferenceDialogFragmentCompat	Implemented a dialog to show ListPreference or MultiSelectListPreference.
LeanbackPreferenceDialogFragmentCompat	A fragment that shows DialogPreference, for example or androidx.preference.MultiSelectListPreference.
LeanbackPreferenceFragmentCompat	This fragment provides a fully decorated leanback-style preference fragment, including a list background and header.
LeanbackSettingsFragmentCompat	This fragment provides a container for displaying a LeanbackPreferenceFragmentCompat
ListFragment	Static library support version of the framework's android.app.ListFragment.
ListPreferenceDialogFragmentCompat
MediaRouteChooserDialogFragment	Media route chooser dialog fragment.
MediaRouteChooserDialog	This class implements the route chooser dialog for MediaRouter.
MediaRouteControllerDialogFragment	Media route controller dialog fragment.
MediaRouteControllerDialog	This class implements the route controller dialog for MediaRouter.
MediaRouteDiscoveryFragment	Media route discovery fragment.
MultiSelectListPreferenceDialogFragmentCompat
NavHostFragment	NavHostFragment provides an area within your layout for self-contained navigation to occur.
OnboardingSupportFragment	An OnboardingSupportFragment provides a common and simple way to build onboarding screen for applications.
PdfViewerFragment	A Fragment that renders a PDF document.
PlaybackSupportFragment	A fragment for displaying playback controls and related content.
PreferenceDialogFragmentCompat	Abstract base class which presents a dialog associated with a DialogPreference.
PreferenceFragmentCompat	A PreferenceFragmentCompat is the entry point to using the Preference library.
PreferenceHeaderFragmentCompat	PreferenceHeaderFragmentCompat implements a two-pane fragment for preferences.
RowsSupportFragment	An ordered set of rows of leanback widgets.
SearchSupportFragment	A fragment to handle searches.
VerticalGridSupportFragment	A fragment for creating leanback vertical grids.
VideoSupportFragment	Subclass of PlaybackSupportFragment that is responsible for providing a SurfaceView and rendering video.

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A scope that owns SavedStateRegistry

This owner should be passed in to create a SavedStateRegistryController object through which this owner can access and perform operations via the controller's SavedStateRegistry

SavedStateRegistryController.performAttach must be called once (and only once) on the main thread during the owner's Lifecycle.State.INITIALIZED state. It should be called before you call SavedStateRegistryController.performRestore

SavedStateRegistryController.performRestore can be called with a nullable if nothing needs to be restored, or with the SavedState to be restored. performRestore can be called in one of two places:

1. Directly before the Lifecycle moves to Lifecycle.State.CREATED

2. Before Lifecycle.State.STARTED is reached, as part of the LifecycleObserver that is added during owner initialization

SavedStateRegistryController.performSave should be called after owner has been stopped but before it reaches Lifecycle.State.DESTROYED state. Hence it should only be called once the owner has received the Lifecycle.Event.ON_STOP event. The SavedState passed to performSave will be the SavedState restored by performRestore.

Summary

Public methods
abstract @NonNull SavedStateRegistry	getSavedStateRegistry() The SavedStateRegistry owned by this SavedStateRegistryOwner

Extension functions
default final @NonNull ReadWriteProperty<Object, @NonNull T>	<T extends Object> SavedStateRegistryOwnerDelegateKt.saved(     @NonNull SavedStateRegistryOwner receiver,     String key,     @NonNull SavedStateConfiguration configuration,     @NonNull Function0<@NonNull T> init ) Returns a property delegate provider that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.
default final @NonNull ReadWriteProperty<Object, @NonNull T>	<T extends Object> SavedStateRegistryOwnerDelegateKt.saved(     @NonNull SavedStateRegistryOwner receiver,     @NonNull <Error class: unknown class><@NonNull T> serializer,     String key,     @NonNull SavedStateConfiguration configuration,     @NonNull Function0<@NonNull T> init ) Returns a property delegate provider that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.

Inherited methods
From androidx.lifecycle.LifecycleOwner abstract @NonNull Lifecycle getLifecycle() Returns the Lifecycle of the provider.

Public methods

getSavedStateRegistry

Added in 1.0.0

abstract @NonNull SavedStateRegistry getSavedStateRegistry()

The SavedStateRegistry owned by this SavedStateRegistryOwner

Extension functions

SavedStateRegistryOwnerDelegateKt.saved

Artifact: androidx.savedstate:savedstate

View Source

default final @NonNull ReadWriteProperty<Object, @NonNull T> <T extends Object> SavedStateRegistryOwnerDelegateKt.saved(
    @NonNull SavedStateRegistryOwner receiver,
    String key,
    @NonNull SavedStateConfiguration configuration,
    @NonNull Function0<@NonNull T> init
)

Returns a property delegate provider that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.

import androidx.activity.ComponentActivity

@Serializable data class User(val id: Int, val name: String)
class MyActivity : ComponentActivity() {
    val user by saved(key = "myKey") { User(id = 123, name = "John Doe") }
}

Parameters
String key	An optional String key to use for storing the value in the SavedStateRegistry. A default key will be generated if it's omitted or when 'null' is passed.
@NonNull SavedStateConfiguration configuration	The SavedStateConfiguration to use. Defaults to SavedStateConfiguration.DEFAULT.
@NonNull Function0<@NonNull T> init	The function to provide the initial value of the property.

Returns
@NonNull ReadWriteProperty<Object, @NonNull T>	A property delegate provider that manages the saving and restoring of the value.

See also
encodeToSavedState
decodeFromSavedState
serializer

SavedStateRegistryOwnerDelegateKt.saved

Artifact: androidx.savedstate:savedstate

View Source

default final @NonNull ReadWriteProperty<Object, @NonNull T> <T extends Object> SavedStateRegistryOwnerDelegateKt.saved(
    @NonNull SavedStateRegistryOwner receiver,
    @NonNull <Error class: unknown class><@NonNull T> serializer,
    String key,
    @NonNull SavedStateConfiguration configuration,
    @NonNull Function0<@NonNull T> init
)

Returns a property delegate provider that manages the saving and restoring of a value of type T within the SavedStateRegistry of this SavedStateRegistryOwner.

import androidx.activity.ComponentActivity

@Serializable data class User(val id: Int, val name: String)
class MyActivity : ComponentActivity() {
    val user by
        saved(key = "myKey", serializer = serializer()) { User(id = 123, name = "John Doe") }
}

Parameters
@NonNull <Error class: unknown class><@NonNull T> serializer	The KSerializer to use for serializing and deserializing the value.
String key	An optional String key to use for storing the value in the SavedStateRegistry. A default key will be generated if it's omitted or when 'null' is passed.
@NonNull SavedStateConfiguration configuration	The SavedStateConfiguration to use. Defaults to SavedStateConfiguration.DEFAULT.
@NonNull Function0<@NonNull T> init	The function to provide the initial value of the property.

Returns
@NonNull ReadWriteProperty<Object, @NonNull T>	A property delegate provider that manages the saving and restoring of the value.

See also
encodeToSavedState
decodeFromSavedState