Class

HKCharacteristicType

A type that represents data that does not typically change over time.

Declaration

class HKCharacteristicType : HKObjectType

Overview

The HKCharacteristicType class is a concrete subclass of the HKObjectType class. To create a characteristic type instance, use the object type’s characteristicType(forIdentifier:) convenience method.

Unlike the other object types, characteristic types cannot be used to create and save new HealthKit objects. Instead, users must enter and edit their characteristic data using the Health app. Similarly, you cannot create queries for characteristic types. Instead, use the HealthKit store to access the data (see Reading Characteristic Data).

HealthKit provides five characteristic types: biological sex, blood type, birthdate, Fitzpatrick skin type, and wheelchair use. These types are used only when asking for permission to read data from the HealthKit store.

Relationships

Inherits From

Conforms To

See Also

Type Objects

class HKQuantityType

A type that identifies samples that store numerical values.

class HKCategoryType

A type that identifies samples that contain a value from a small set of possible values.

class HKCorrelationType

A type that identifies samples that group multiple subsamples.

class HKActivitySummaryType

A type that identifies activity summary objects.

class HKAudiogramSampleType

A type that identifies samples that contain audiogram data.

Beta
class HKSeriesType

A type that indicates the data stored in a series sample.

class HKObjectType

The abstract superclass for all classes that identify a specific type of data when working with the HealthKit store.

class HKSampleType

An abstract superclass for all classes that identify a specific type of sample when working with the HealthKit store.

class HKClinicalType

A type that identifies samples that contain clinical record data.

class HKWorkoutType

A type that identifies samples that store information about a workout.

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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