NavBackStackEntry

class NavBackStackEntry : LifecycleOwner, ViewModelStoreOwner, HasDefaultViewModelProviderFactory, SavedStateRegistryOwner

Representation of an entry in the back stack of a androidx.navigation.NavController. The Lifecycle, ViewModelStore, and SavedStateRegistry provided via this object are valid for the lifetime of this destination on the back stack: when this destination is popped off the back stack, the lifecycle will be destroyed, state will no longer be saved, and ViewModels will be cleared.

Summary

Public functions
open operator Boolean
equals(other: Any?)
open Int
open String

Public properties
SavedState?

The arguments used for this entry.
open CreationExtras
open ViewModelProvider.Factory
NavDestination

The destination associated with this entry
String

The unique ID that serves as the identity of this entry
open Lifecycle

{@inheritDoc}
SavedStateHandle

The SavedStateHandle for this entry.
open SavedStateRegistry
open ViewModelStore

Extension functions
inline T

Returns route as an object of type T
T
<T : Any?> NavBackStackEntry.toRoute(route: KClass<*>)

Returns route as an object of type T
Unit
@Composable
NavBackStackEntry.LocalOwnersProvider(
    saveableStateHolder: SaveableStateHolder,
    content: @Composable () -> Unit
)

Provides this as LocalViewModelStoreOwner, LocalLifecycleOwner and LocalSavedStateRegistryOwner to the content and saves the content's saveable states with the given saveableStateHolder.

Public functions

equals

open operator fun equals(other: Any?): Boolean

hashCode

open fun hashCode(): Int

toString

open fun toString(): String

Public properties

arguments

Added in 2.2.0
val arguments: SavedState?

The arguments used for this entry. Note that the arguments of a NavBackStackEntry are immutable and defined when you navigate() to the destination - changes you make to this SavedState will not be reflected in future calls to this property.

Returns
SavedState?

The arguments used when this entry was created

defaultViewModelCreationExtras

open val defaultViewModelCreationExtras: CreationExtras

defaultViewModelProviderFactory

Added in 2.2.0
open val defaultViewModelProviderFactory: ViewModelProvider.Factory

destination

Added in 2.2.0
val destination: NavDestination

The destination associated with this entry

Returns
NavDestination

The destination that is currently visible to users

id

val id: String

The unique ID that serves as the identity of this entry

Returns
String

the unique ID of this entry

lifecycle

Added in 2.2.0
open val lifecycle: Lifecycle

{@inheritDoc}

If the androidx.navigation.NavHost has not called androidx.navigation.NavHostController.setLifecycleOwner, the Lifecycle will be capped at Lifecycle.State.CREATED.

savedStateHandle

Added in 2.3.0
val savedStateHandle: SavedStateHandle

The SavedStateHandle for this entry.

savedStateRegistry

Added in 2.2.0
open val savedStateRegistry: SavedStateRegistry

viewModelStore

Added in 2.2.0
open val viewModelStore: ViewModelStore

Extension functions

toRoute

inline fun <T : Any?> NavBackStackEntry.toRoute(): T

Returns route as an object of type T

Extrapolates arguments from NavBackStackEntry.arguments and recreates object T

Parameters
<T : Any?>

the entry's NavDestination.route as a KClass
Returns
T

A new instance of this entry's NavDestination.route as an object of type T

toRoute

fun <T : Any?> NavBackStackEntry.toRoute(route: KClass<*>): T

Returns route as an object of type T

Extrapolates arguments from NavBackStackEntry.arguments and recreates object T

Parameters
route: KClass<*>

the entry's NavDestination.route as a KClass
Returns
T

A new instance of this entry's NavDestination.route as an object of type T

LocalOwnersProvider

@Composable
fun NavBackStackEntry.LocalOwnersProvider(
    saveableStateHolder: SaveableStateHolder,
    content: @Composable () -> Unit
): Unit

Provides this as LocalViewModelStoreOwner, LocalLifecycleOwner and LocalSavedStateRegistryOwner to the content and saves the content's saveable states with the given saveableStateHolder.

Parameters
saveableStateHolder: SaveableStateHolder

The SaveableStateHolder that holds the saved states. The same holder should be used for all NavBackStackEntrys in the encapsulating Composable and the holder should be hoisted.
content: @Composable () -> Unit

The content Composable