# ViewModelStoreProvider Artifact: [androidx.lifecycle:lifecycle-viewmodel-savedstate](https://developer.android.com/jetpack/androidx/releases/lifecycle) [View Source](https://cs.android.com/search?q=file:androidx/lifecycle/viewmodel/ViewModelStoreProvider.kt+class:androidx.lifecycle.viewmodel.ViewModelStoreProvider) Added in [2.11.0](https://developer.android.com/jetpack/androidx/releases/lifecycle#2.11.0) *** ** * ** *** ``` public final class ViewModelStoreProvider ```
*** ** * ** *** Manages a set of child `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` instances scoped to a parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore`. This class allows the creation of child `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` instances that survive configuration changes (retained via the parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore`) but can be independently cleared when no longer needed. **Important:** This class prevents a child `https://developer.android.com/reference/androidx/lifecycle/ViewModel` from being cleared while they are still in use (e.g., during exit animations). Consumers must call `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)` to mark a child `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` as active and then call `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-auto-closeable/close.html` to release the token when finished. Calling `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearKey(kotlin.Any)` or `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearAllKeys()` will only perform the actual cleanup once all of a store's tokens have been released. **Null parentStore:** If `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#parentStore()` is **EXPLICITLY** `null`, this creates a root provider that runs independently. It manages its own state and will not be automatically cleared by configuration changes; you must manually call `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearAllKeys()` to clean it up. ## Summary | ### Nested types | |---| | `public static class https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ProviderMarkerKey` A special marker key that can be used with `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)` to manage the lifecycle of the shared state associated with a particular `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#parentKey()`. | | `public fun interface https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ReferenceToken extends https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-auto-closeable/index.html` Represents an active hold on a specific `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore`. | | ### Public constructors | |---| | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#ViewModelStoreProvider(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)( https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner parentOwner, https://developer.android.com/reference/java/lang/Object.html parentKey, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory )` Constructs a `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider` bound to a parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner`. | | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#ViewModelStoreProvider(androidx.lifecycle.ViewModelStore,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)( https://developer.android.com/reference/androidx/lifecycle/ViewModelStore parentStore, https://developer.android.com/reference/java/lang/Object.html parentKey, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory )` | | ### Public methods | |---|---| | `final @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ReferenceToken` | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)(https://developer.android.com/reference/java/lang/Object.html key)` Increments the reference count for the `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)`, ensuring it is not cleared until the returned `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ReferenceToken` is released. | | `final void` | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearAllKeys()()` Triggers a cleanup pass on all managed stores. | | `final void` | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearKey(kotlin.Any)(https://developer.android.com/reference/java/lang/Object.html key)` Marks the `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearKey(kotlin.Any)` as removable. | | `final @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreate(kotlin.Any)(https://developer.android.com/reference/java/lang/Object.html key)` Retrieves or creates a `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreate(kotlin.Any)`. | | `final @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` | `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)( https://developer.android.com/reference/java/lang/Object.html key, https://developer.android.com/reference/androidx/savedstate/SavedStateRegistryOwner savedStateRegistryOwner, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras, @https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory )` Retrieves or creates a `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. | ## Public constructors ### ViewModelStoreProvider ``` public ViewModelStoreProvider(     ViewModelStoreOwner parentOwner,     Object parentKey,     @NonNull SavedState defaultArgs,     @NonNull CreationExtras defaultCreationExtras,     @NonNull ViewModelProvider.Factory defaultFactory ) ``` Constructs a `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider` bound to a parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner`. | Parameters | |---|---| | `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner parentOwner` | The parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` whose `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` is used to retain child `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` instances across configuration changes, or `null` for an independent root provider. | | `https://developer.android.com/reference/java/lang/Object.html parentKey` | A unique identifier used to scope this provider and its underlying state within the `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. Providers sharing the same key will share the same internal state. A `null` key is valid and acts as its own distinct shared scope. Defaults to `null`. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs` | The default `https://developer.android.com/reference/androidx/savedstate/SavedState` arguments to use for child stores. These arguments are merged with any default arguments in `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. If the same key exists in both, the value from `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)` takes precedence. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras` | The default creation extras to use for child stores. Defaults to resolving from the `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory` | The default factory to use for child stores. Defaults to resolving from the `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#(androidx.lifecycle.ViewModelStoreOwner,kotlin.Any,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. | ### ViewModelStoreProvider ``` public ViewModelStoreProvider(     ViewModelStore parentStore,     Object parentKey,     @NonNull SavedState defaultArgs,     @NonNull CreationExtras defaultCreationExtras,     @NonNull ViewModelProvider.Factory defaultFactory ) ``` | Parameters | |---|---| | `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore parentStore` | The parent `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` used to retain child `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` instances across configuration changes, or `null` for an independent root provider. | | `https://developer.android.com/reference/java/lang/Object.html parentKey` | A unique identifier used to scope this provider and its underlying state within the `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#parentStore()`. Providers sharing the same key will share the same internal state. A `null` key is valid and acts as its own distinct shared scope. Defaults to `null`. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs` | The default `https://developer.android.com/reference/androidx/savedstate/SavedState` arguments to use for child stores. These arguments are merged with any default arguments in `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#defaultCreationExtras()`. If the same key exists in both, the value from `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#defaultArgs()` takes precedence. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras` | The default creation extras to use for child stores. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory` | The default factory to use for child stores. | ## Public methods ### acquireToken Added in [2.11.0](https://developer.android.com/jetpack/androidx/releases/lifecycle#2.11.0) ``` public final @NonNull ViewModelStoreProvider.ReferenceToken acquireToken(Object key) ``` Increments the reference count for the `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)`, ensuring it is not cleared until the returned `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ReferenceToken` is released. | Parameters | |---|---| | `https://developer.android.com/reference/java/lang/Object.html key` | The unique identifier for the child scope. A `null` key is valid and is treated as a distinct scope. | | Returns | |---|---| | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider.ReferenceToken` | A token that must be released via `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-auto-closeable/close.html` when the caller no longer requires the store. | ### clearAllKeys Added in [2.11.0](https://developer.android.com/jetpack/androidx/releases/lifecycle#2.11.0) ``` public final void clearAllKeys() ``` Triggers a cleanup pass on all managed stores. Any `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` that has a reference count of zero will have its `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore#clear()` method called and will be removed from the internal map. Stores with active references are marked as removable and will be deferred until their count reaches zero. ### clearKey Added in [2.11.0](https://developer.android.com/jetpack/androidx/releases/lifecycle#2.11.0) ``` public final void clearKey(Object key) ``` Marks the `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#clearKey(kotlin.Any)` as removable. If the store currently has a reference count of zero, it is cleared immediately. Otherwise, the actual cleanup is deferred until all acquired tokens are released. | Parameters | |---|---| | `https://developer.android.com/reference/java/lang/Object.html key` | The unique identifier for the child scope. Passing `null` will target the specific scope associated with the `null` key. | ### getOrCreate Added in [2.11.0](https://developer.android.com/jetpack/androidx/releases/lifecycle#2.11.0) ``` public final @NonNull ViewModelStore getOrCreate(Object key) ``` Retrieves or creates a `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreate(kotlin.Any)`. If a store with this key already exists, it is returned. If not, a new store is created. To protect this store from being prematurely cleared, you must call `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)`. | Parameters | |---|---| | `https://developer.android.com/reference/java/lang/Object.html key` | The unique identifier for the child scope. A `null` key is valid and is treated as a distinct scope. | | Returns | |---|---| | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` | The `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore` tied to the provided key. | ### getOrCreateOwner ``` public final @NonNull ViewModelStoreOwner getOrCreateOwner(     Object key,     SavedStateRegistryOwner savedStateRegistryOwner,     @NonNull SavedState defaultArgs,     @NonNull CreationExtras defaultCreationExtras,     @NonNull ViewModelProvider.Factory defaultFactory ) ``` Retrieves or creates a `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` associated with the given `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. This method creates a new lightweight wrapper around the `https://developer.android.com/reference/androidx/lifecycle/ViewModelStore`. **Important:** This does *not* automatically increment the reference count. If you are holding onto this owner asynchronously or across recompositions, you should call `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#acquireToken(kotlin.Any)` to protect its lifecycle. **Saved State Support:** If a `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)` is provided, the returned `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` will also implement `https://developer.android.com/reference/androidx/savedstate/SavedStateRegistryOwner`, delegating state resolution to the provided owner. This is required if ViewModels within this scope depend on `https://developer.android.com/reference/androidx/lifecycle/SavedStateHandle`. When saved state is enabled and `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)` is not explicitly overridden, it automatically upgrades to a `https://developer.android.com/reference/androidx/lifecycle/SavedStateViewModelFactory`. | Parameters | |---|---| | `https://developer.android.com/reference/java/lang/Object.html key` | The unique identifier for the child scope. A `null` key is valid and is treated as a distinct scope. | | `https://developer.android.com/reference/androidx/savedstate/SavedStateRegistryOwner savedStateRegistryOwner` | An optional parent registry owner to delegate saved state operations to. If `null`, the returned owner will not support `https://developer.android.com/reference/androidx/lifecycle/SavedStateHandle`. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/savedstate/SavedState defaultArgs` | The default `https://developer.android.com/reference/androidx/savedstate/SavedState` arguments to use for child stores. These arguments are merged with any default arguments in `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)`. If the same key exists in both, the value from `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)` takes precedence. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras defaultCreationExtras` | An optional override for the default `https://developer.android.com/reference/androidx/lifecycle/viewmodel/CreationExtras`. | | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory defaultFactory` | An optional override for the default `https://developer.android.com/reference/androidx/lifecycle/ViewModelProvider.Factory`. | | Returns | |---|---| | `@https://developer.android.com/reference/androidx/annotation/NonNull https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner` | A scoped `https://developer.android.com/reference/androidx/lifecycle/ViewModelStoreOwner`, which optionally supports saved state. | | Throws | |---|---| | `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-illegal-argument-exception/index.html` | If `https://developer.android.com/reference/androidx/lifecycle/viewmodel/ViewModelStoreProvider#getOrCreateOwner(kotlin.Any,androidx.savedstate.SavedStateRegistryOwner,androidx.savedstate.SavedState,androidx.lifecycle.viewmodel.CreationExtras,androidx.lifecycle.ViewModelProvider.Factory)` is provided but its lifecycle is past the INITIALIZED or CREATED state. |