Accessing resting heart rate - ios

Question

Good Day,
I'm a novice at Swift 4 and am having a trouble getting resting heart rate data.
Here is what I have:
// Declarations
var heartRateType = HKAnchoredObjectQuery.self
private func createStreamingQuery() -> HKQuery {
let calendar = NSCalendar.current;
let now = NSDate();
let sevenDaysAgo = calendar.date(byAdding: .day, value: -7, to: now as Date);
let startDate = calendar.startOfDay(for: sevenDaysAgo!);
let predicate = HKQuery.predicateForSamples(withStart: startDate as Date, end: now as Date, options: [])
let query = HKAnchoredObjectQuery(type: heartRateType, predicate: predicate, anchor: nil, limit: Int(HKObjectQueryNoLimit)) {
(query, samples, deletedObjects, anchor, error) -> Void in
self.formatSamples(samples: samples)
}
query.updateHandler = { (query, samples, deletedObjects, anchor, error) -> Void in
self.formatSamples(samples: samples)
}
return query
}
#IBAction func readHeartRate(_ sender: Any) {
self.healthKitStore.execute(self.createStreamingQuery())
}
private func formatSamples(samples: [HKSample]?) {
guard let heartRateSamples = samples as? [HKQuantitySample] else { return }
guard let sample = heartRateSamples.first else{return}
let value = sample.quantity.doubleValue(for: heartRateType)
print("HeartRate: \(value)")
}
I'm getting the following errors with these lines and can't check to see if this will even work.
// Error: Generic parameter 'T' could not be inferred
// Code with error:
let query = HKAnchoredObjectQuery(type: heartRateType, predicate: predicate, anchor: nil, limit: Int(HKObjectQueryNoLimit)) {
(query, samples, deletedObjects, anchor, error) -> Void in
self.formatSamples(samples: samples)
}
The other error: Cannot convert value of type 'HKAnchoredObjectQuery.Type' to expected argument type 'HKUnit'
// Code with error:
let value = sample.quantity.doubleValue(for: heartRateType)
Any assistance you can provide is greatly appreciated.
Thank you so much!
Kevin

Answer 1

Since I posted this, I've researched and learn more about this. I ended up rewriting the function to the following:
//MARK: - Get Users Resting Heart Rate
func getUsersRestingHeartRate(completion: #escaping (HKQuantitySample) -> Void) {
// print("getUsersRestingHeartRate(Completion)")
guard let restingHeartRateSampleType = HKSampleType.quantityType(forIdentifier: .restingHeartRate) else {
print("Resting Heart Rate Sample Type is no longer available in HealthKit")
return
}
//1. Use HKQuery to load the most recent samples.
let mostRecentPredicate = HKQuery.predicateForSamples(withStart: Date.distantPast,
end: Date(),
options: .strictEndDate)
let sortDescriptor = NSSortDescriptor(key: HKSampleSortIdentifierStartDate, ascending: false)
let sampleQuery = HKSampleQuery(sampleType: restingHeartRateSampleType,
predicate: mostRecentPredicate,
limit: HKObjectQueryNoLimit,
sortDescriptors:
[sortDescriptor]) { (query, samples, error) in
DispatchQueue.main.async {
guard let samples = samples,
let mostRecentSample = samples.first as? HKQuantitySample else {
print("getUserRestingHeartRate sample is missing")
return
}
completion(mostRecentSample)
}
}
HKHealthStore().execute(sampleQuery)
}