# CLSDataStore A container for all the ClassKit data in your app. ``` class CLSDataStore ``` ## Overview Use the ClassKit data store to build and access contexts ([`CLSContext`](/documentation/ClassKit/CLSContext) instances) that you use to advertise your app’s assignable content. Contexts in turn provide access to activities ([`CLSActivity`](/documentation/ClassKit/CLSActivity) instances) and activity items ([`CLSScoreItem`](/documentation/ClassKit/CLSScoreItem), [`CLSBinaryItem`](/documentation/ClassKit/CLSBinaryItem), and [`CLSQuantityItem`](/documentation/ClassKit/CLSQuantityItem) instances) that you use to record progress through assignments. You don’t instantiate a data store yourself. Instead, use the single [`shared`](/documentation/ClassKit/CLSDataStore/shared) data store instance throughout your app. The data store provides access to the app’s one and only main context through the [`mainAppContext`](/documentation/ClassKit/CLSDataStore/mainAppContext) property. This property acts as the root context in your context hierarchy that you can use as a starting point when searching for descendant contexts. To build contexts, you adopt the [`CLSDataStoreDelegate`](/documentation/ClassKit/CLSDataStoreDelegate) protocol in one of your classes, typically one that exists for the lifetime of your app, and assign an instance of that class as the shared data store’s [`delegate`](/documentation/ClassKit/CLSDataStore/delegate) property. Then, when the data store needs a context that it’s never seen before, it asks your delegate to build it. After you make changes to any context, activity, or activity item, call the data store’s [`save(completion:)`](/documentation/ClassKit/CLSDataStore/save(completion:)) method to commit the changes, and propagate them through the network. ## Topics ### Accessing the shared data store [`shared`](/documentation/ClassKit/CLSDataStore/shared) The shared data store object. ### Managing the delegate [`delegate`](/documentation/ClassKit/CLSDataStore/delegate) The data store delegate instance. [`CLSDataStoreDelegate`](/documentation/ClassKit/CLSDataStoreDelegate) An interface the data store uses to request new contexts. ### Accessing specific contexts and activities [`mainAppContext`](/documentation/ClassKit/CLSDataStore/mainAppContext) The app’s top-level context. [`activeContext`](/documentation/ClassKit/CLSDataStore/activeContext) The currently active context. [`runningActivity`](/documentation/ClassKit/CLSDataStore/runningActivity) The currently running activity within the currently active context. [`- fetchActivityForURL:completion:`](/documentation/ClassKit/CLSDataStore/fetchActivity(for:completion:)) Fetches an activity for a given document so you can record progress on the associated task. [`- completeAllAssignedActivitiesMatching:`](/documentation/ClassKit/CLSDataStore/completeAllAssignedActivities(matching:)) Marks all of the assigned and active activities for the given context path as complete. ### Finding contexts that match criteria [`- contextsMatchingIdentifierPath:completion:`](/documentation/ClassKit/CLSDataStore/contexts(matchingIdentifierPath:completion:)) Fetches all the contexts along a given identifier path. [`- contextsMatchingPredicate:completion:`](/documentation/ClassKit/CLSDataStore/contexts(matching:completion:)) Fetches all the contexts matching a predicate. [`CLSPredicateKeyPath`](/documentation/ClassKit/CLSPredicateKeyPath) The set of possible key paths you use to search for contexts. ### Removing contexts [`- removeContext:`](/documentation/ClassKit/CLSDataStore/remove(_:)) Marks a context for removal. ### Saving changes [`- saveWithCompletion:`](/documentation/ClassKit/CLSDataStore/save(completion:)) Saves any changes you’ve made in the data store. ## Relationships ### Conforms To [`Hashable`](/documentation/Swift/Hashable) [`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible) [`Equatable`](/documentation/Swift/Equatable) [`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol) [`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible) [`CVarArg`](/documentation/Swift/CVarArg) ### Inherits From [`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class) --- 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)