Class

HKObject

A piece of data that can be stored inside the HealthKit store.

Declaration

class HKObject : NSObject

Overview

The HKObject class is an abstract class. You should never instantiate a HKObject object directly. Instead, always work with one of its concrete subclasses: HKCategorySample, HKQuantitySample, HKCorrelation, or HKWorkout.

HealthKit objects are all immutable. With a few exceptions (such as the object’s source revision), the object’s properties are set when the object is first created and they cannot change.

Topics

Getting Properties

var uuid: UUID

The universally unique identifier (UUID) for this HealthKit object.

var metadata: [String : Any]?

The metadata for this HealthKit object.

var device: HKDevice?

The device that generated the data for this object.

var source: HKSource

A HealthKit source, representing the app or device that created this object.

Deprecated
var sourceRevision: HKSourceRevision

The app or device that created this object.

Predicate Key Paths

let HKPredicateKeyPathUUID: String

The key path for accessing the object’s UUID inside a predicate format string.

let HKPredicateKeyPathMetadata: String

The key path for accessing the object’s metadata dictionary inside a predicate format string.

Relationships

Inherits From

See Also

Abstract Superclasses

class HKQuantitySample

A sample that represents a quantity, including the value and the units.

class HKSample

A HealthKit sample represents a piece of data associated with a start and end time.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

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