How to display steps count from HealthKit Swift 3 - ios

Question

Hi i want to display on my app dayly step count from healthKit
This is my code:
imports
import UIKit
import HealthKit
Class instance
var healthStore = HKHealthStore()
viewDidLoad method
override func viewDidLoad() {
super.viewDidLoad()
if HKHealthStore.isHealthDataAvailable(){
let writeDataTypes = dataTypesToWrite()
let readDataTypes = dataTypesToWrite()
healthStore.requestAuthorization(toShare: writeDataTypes as? Set<HKSampleType>, read: readDataTypes as? Set<HKObjectType>, completion: { (success, error) in
if(!success){
print("error")
return
}
self.updateSteps()
})
}
}
Write:
func dataTypesToWrite() -> NSSet{
let stepsCount = HKObjectType.quantityType(forIdentifier: HKQuantityTypeIdentifier.stepCount)
let returnSet = NSSet(objects: stepsCount!)
return returnSet
}
Read:
func dataTypesToRead() -> NSSet{
let stepsCount = HKQuantityType.quantityType(forIdentifier: HKQuantityTypeIdentifier.stepCount)
let returnSet = NSSet(objects: stepsCount!)
return returnSet
}
Now I want to create func updateSteps()

Answer 1

I have an answer to my question
func updateSteps(completion: #escaping (Double) -> Void) {
let stepsQuantityType = HKQuantityType.quantityType(forIdentifier: .stepCount)!
let now = Date()
let startOfDay = Calendar.current.startOfDay(for: now)
let predicate = HKQuery.predicateForSamples(withStart: startOfDay, end: now, options: .strictStartDate)
let query = HKStatisticsQuery(quantityType: stepsQuantityType, quantitySamplePredicate: predicate, options: .cumulativeSum) { (_, result, error) in
var resultCount = 0.0
guard let result = result else {
print("\(String(describing: error?.localizedDescription)) ")
completion(resultCount)
return
}
if let sum = result.sumQuantity() {
resultCount = sum.doubleValue(for: HKUnit.count())
}
DispatchQueue.main.async {
completion(resultCount)
}
}
healthStore.execute(query)
}