# AssetPackManager An actor that manages asset packs. ``` actor AssetPackManager ``` ## Overview The first time that your code refers to the shared manager, Background Assets considers that your app is opting into automatic system management of your asset packs. > Important: When using the asset-pack manager, make sure that you also adopt the corresponding managed extension protocol, ``doc://com.apple.backgroundassets/documentation/BackgroundAssets/ManagedDownloaderExtension`` (for self-hosted asset packs) or `StoreDownloaderExtension` from StoreKit (for Apple-hosted asset packs). Not doing so is a programmer error. ## Topics ### Getting the shared manager [`static let shared: AssetPackManager`](/documentation/BackgroundAssets/AssetPackManager/shared) The shared manager. ### Tracking downloads [`let statusUpdates: some Sendable & AsyncSequence`](/documentation/BackgroundAssets/AssetPackManager/statusUpdates) An asynchronous sequence of download-status updates for all asset packs. [`func statusUpdates(forAssetPackWithID: String) -> some Sendable & AsyncSequence`](/documentation/BackgroundAssets/AssetPackManager/statusUpdates(forAssetPackWithID:)) Returns an asynchronous sequence of download-status updates for the asset pack with the specified ID. [`enum DownloadStatusUpdate`](/documentation/BackgroundAssets/AssetPackManager/DownloadStatusUpdate) Statuses of an asset-pack download. ### Accessing asset packs [`var manifest: AssetPackManifest`](/documentation/BackgroundAssets/AssetPackManager/manifest) The manifest of asset packs that are available to download. [`struct AssetPackManifest`](/documentation/BackgroundAssets/AssetPackManifest) A manifest of asset packs that are available to download. [`var allAssetPacks: Set`](/documentation/BackgroundAssets/AssetPackManager/allAssetPacks) The asset packs that are available to download. [`func assetPack(withID: String) async throws -> AssetPack`](/documentation/BackgroundAssets/AssetPackManager/assetPack(withID:)) Returns the asset pack with the given ID. ### Accessing asset contents [`func contents(at: FilePath, searchingInAssetPackWithID: String?, options: Data.ReadingOptions) throws -> Data`](/documentation/BackgroundAssets/AssetPackManager/contents(at:searchingInAssetPackWithID:options:)) Returns the contents of an asset file at the specified relative path. [`func contents(at: FilePath, asLocalizedFor: Locale.Language, options: Data.ReadingOptions) throws -> Data`](/documentation/BackgroundAssets/AssetPackManager/contents(at:asLocalizedFor:options:)) Returns the contents of a localized asset file at the specified relative path. [`func descriptor(for: FilePath, searchingInAssetPackWithID: String?) throws -> FileDescriptor`](/documentation/BackgroundAssets/AssetPackManager/descriptor(for:searchingInAssetPackWithID:)) Opens and returns a file descriptor for an asset file at the specified relative path. [`func descriptor(for: FilePath, asLocalizedFor: Locale.Language) throws -> FileDescriptor`](/documentation/BackgroundAssets/AssetPackManager/descriptor(for:asLocalizedFor:)) Opens and returns a file descriptor for a localized asset file at the specified relative path. [`func url(for: FilePath) throws -> URL`](/documentation/BackgroundAssets/AssetPackManager/url(for:)) Returns a URL for the specified relative path. [`func url(for: FilePath, asLocalizedFor: Locale.Language) throws -> URL`](/documentation/BackgroundAssets/AssetPackManager/url(for:asLocalizedFor:)) Returns a URL for the specified relative path. ### Managing asset packs [`func checkForUpdates() async throws -> (updatingIDs: Set, removedIDs: Set)`](/documentation/BackgroundAssets/AssetPackManager/checkForUpdates()) Gets the latest asset-pack information from the server, updates outdated asset packs, and removes obsolete asset packs. [`func ensureLocalAvailability(of: AssetPack, requireLatestVersion: Bool) async throws`](/documentation/BackgroundAssets/AssetPackManager/ensureLocalAvailability(of:requireLatestVersion:)) Ensures that an asset pack is available locally, performing a download if necessary. [`func ensureLocalAvailability(of: Set, requireLatestVersions: Bool) async throws`](/documentation/BackgroundAssets/AssetPackManager/ensureLocalAvailability(of:requireLatestVersions:)) Ensures the specified asset packs are available locally, performing a batch download if necessary. [`func assetPackIsAvailableLocally(withID: String) -> Bool`](/documentation/BackgroundAssets/AssetPackManager/assetPackIsAvailableLocally(withID:)) Checks whether an asset pack is available locally. [`func status(relativeTo: AssetPack) async throws -> AssetPack.Status`](/documentation/BackgroundAssets/AssetPackManager/status(relativeTo:)) Checks the current status relative to a particular asset pack. [`func localStatus(ofAssetPackWithID: String) async -> AssetPack.Status`](/documentation/BackgroundAssets/AssetPackManager/localStatus(ofAssetPackWithID:)) Checks an asset pack’s local status. [`struct Status`](/documentation/BackgroundAssets/AssetPack/Status) The status of an asset pack. [`func remove(assetPackWithID: String) async throws`](/documentation/BackgroundAssets/AssetPackManager/remove(assetPackWithID:)) Removes the specified asset pack from the device. [`func status(ofAssetPackWithID: String) async throws -> AssetPack.Status`](/documentation/BackgroundAssets/AssetPackManager/status(ofAssetPackWithID:)) Checks an asset pack’s status. [`func ensureLocalAvailability(of: AssetPack) async throws`](/documentation/BackgroundAssets/AssetPackManager/ensureLocalAvailability(of:)) Ensures that the specified asset pack is available locally, performing a download if necessary. ### Inspecting language support [`var locallyAvailableLanguages: [Locale.Language]`](/documentation/BackgroundAssets/AssetPackManager/locallyAvailableLanguages) The languages used by asset packs that are localized and are available locally. [`var resolvedLanguage: Locale.Language?`](/documentation/BackgroundAssets/AssetPackManager/resolvedLanguage) The language that best matches current preferences and for which the system automatically makes localized asset packs available locally. [`func reconcilePreferredLanguages() async throws`](/documentation/BackgroundAssets/AssetPackManager/reconcilePreferredLanguages()) Reconciles the set of locally available asset packs with the current preferred languages. ### Handling errors [`struct LocalAvailabilityError`](/documentation/BackgroundAssets/AssetPackManager/LocalAvailabilityError) An error that provides information about local asset pack availability, distinguishing between successes and failures. ### Instance Methods [`func localSize(ofAssetPackWithID: String, calculationMethod: SizeCalculationMethod) async throws -> Int64`](/documentation/BackgroundAssets/AssetPackManager/localSize(ofAssetPackWithID:calculationMethod:)) Calculates a locally available asset pack’s installation size. [`func localVersion(ofAssetPackWithID: String) throws -> Int`](/documentation/BackgroundAssets/AssetPackManager/localVersion(ofAssetPackWithID:)) Returns a locally available asset pack’s version number. ## Relationships ### Conforms To [`Sendable`](/documentation/Swift/Sendable) [`Actor`](/documentation/Swift/Actor) [`SendableMetatype`](/documentation/Swift/SendableMetatype) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)