Read Blood group, Age, Gender etc from HealthKit in Swift - ios

Question

I am trying to read Personal Details (Blood group, Age, Gender) of Healthkit but unable to request for that.
As per Apple Doc here:
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.
But i can't make add HKCharacteristicType in authorisation request.
I have run Apple Sample Project which requests for:
HKQuantityTypeIdentifier.stepCount.rawValue,
HKQuantityTypeIdentifier.distanceWalkingRunning.rawValue,
HKQuantityTypeIdentifier.sixMinuteWalkTestDistance.rawValue
But when I add
HKCharacteristicTypeIdentifier.bloodType.rawValue
HKCharacteristicTypeIdentifier.dateOfBirth.rawValue
The permission screen does not asks for DOB and Blood Type. See Image:
Configuration: Simulator iOS 15.4 and Xcode 13.3
Anyone knows that if we can access Personal Data of HealthKit or not. Please help me out.

Answer 1

This is happening because bloodType and dateOfBirth are of type HKCharacteristicType
when you call this, the compactMap operation will not include your types
private static var allHealthDataTypes: [HKSampleType] {
let typeIdentifiers: [String] = [
HKQuantityTypeIdentifier.stepCount.rawValue,
HKQuantityTypeIdentifier.distanceWalkingRunning.rawValue,
HKQuantityTypeIdentifier.sixMinuteWalkTestDistance.rawValue,
HKCharacteristicTypeIdentifier.bloodType.rawValue,
HKCharacteristicTypeIdentifier.dateOfBirth.rawValue
]
return typeIdentifiers.compactMap { getSampleType(for: $0) }
}
check getSampleType:
func getSampleType(for identifier: String) -> HKSampleType? {
if let quantityType = HKQuantityType.quantityType(forIdentifier: HKQuantityTypeIdentifier(rawValue: identifier)) {
return quantityType
}
if let categoryType = HKCategoryType.categoryType(forIdentifier: HKCategoryTypeIdentifier(rawValue: identifier)) {
return categoryType
}
return nil
}
your types won't fall into any of these if let, so this function will return nil. You must change the code so you are able to use HKCharacteristicTypeIdentifier as well.
EDIT: An easy way to do this is changing the readDataTypes in HealthData class to:
static var readDataTypes: [HKObjectType] {
return allHealthDataTypes + [
HKObjectType.characteristicType(forIdentifier: .dateOfBirth)!,
HKObjectType.characteristicType(forIdentifier: .bloodType)!
]
}

Answer 2

You can only request read authorization for the HKCharacteristicTypes, not share authorization. Update your code to add these 2 data types only to the readDataTypes variable. Right now you are requesting both read & share for the characteristic types, which is why they are not appearing on the authorization sheet.