How to obtain Health data from the last 7 days - ios

Question

I'm trying to obtain the steps from the last 7 days, but I could not find how to do it. What i would like to receive is an array of 7 elements in which every element is a Day with it respectives total steps. I currently have this code, which obtains today's steps:
//Gets the steps
func getTodaysSteps(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
guard let result = result, let sum = result.sumQuantity() else {
print("Failed to fetch steps = \(error?.localizedDescription ?? "N/A")")
completion(0.0)
return
}
DispatchQueue.main.async {
completion(sum.doubleValue(for: HKUnit.count()))
}
}
healthKitStore.execute(query)
}
And I call the function like this:
getTodaysSteps { (steps) in
self.stepsNumber = Int(steps)
}

Answer 1

Try using HKStatisticsCollectionQuery, which will do the date math for you and bucket the results automatically. Here's an example that should provide the step counts for the last 7 days:
let stepsQuantityType = HKQuantityType.quantityType(forIdentifier: .stepCount)!
let now = Date()
let exactlySevenDaysAgo = Calendar.current.date(byAdding: DateComponents(day: -7), to: now)!
let startOfSevenDaysAgo = Calendar.current.startOfDay(for: exactlySevenDaysAgo)
let predicate = HKQuery.predicateForSamples(withStart: startOfSevenDaysAgo, end: now, options: .strictStartDate)
let query = HKStatisticsCollectionQuery.init(quantityType: stepsQuantityType,
quantitySamplePredicate: predicate,
options: .cumulativeSum,
anchorDate: startOfSevenDaysAgo,
intervalComponents: DateComponents(day: 1))
query.initialResultsHandler = { query, results, error in
guard let statsCollection = results else {
// Perform proper error handling here...
}
statsCollection.enumerateStatistics(from: startOfSevenDaysAgo, to: now) { statistics, stop in
if let quantity = statistics.sumQuantity() {
let stepValue = quantity.doubleValueForUnit(HKUnit.countUnit())
// ...
}
}
}

Answer 2

There's even more simpler solution here.
func getTotalSteps(forPast days: Int, completion: #escaping (Double) -> Void) {
// Getting quantityType as stepCount
guard let stepsQuantityType = HKObjectType.quantityType(forIdentifier: .stepCount) else {
print("*** Unable to create a step count type ***")
return
}
let now = Date()
let startDate = Calendar.current.date(byAdding: DateComponents(day: -days), to: now)
let predicate = HKQuery.predicateForSamples(withStart: startDate, end: now, options: .strictStartDate)
let query = HKStatisticsQuery(quantityType: stepsQuantityType, quantitySamplePredicate: predicate, options: .cumulativeSum) { _, result, _ in
guard let result = result, let sum = result.sumQuantity() else {
completion(0.0)
return
}
completion(sum.doubleValue(for: HKUnit.count()))
}
execute(query)
}
Now to call just use the following code:
HKHealthStore().getTotalSteps(forPast: 30) { totalSteps in
print(totalSteps)
}

Answer 3

The only change you have to implement is to change the Date object you supply as the startWith parameter to your HKStatisticsQuery. You can create a Date object representing the start of the day 7 days ago by first going back exactly 7 days in time using Calendar.date(byAdding:,to:), then calling startOfDay(for:) on that object.
let now = Date()
let exactlySevenDaysAgo = Calendar.current.date(byAdding: DateComponents(day: -7), to: now)!
let startOfSevenDaysAgo = Calendar.current.startOfDay(for: exactlySevenDaysAgo)
let predicate = HKQuery.predicateForSamples(withStart: startOfSevenDaysAgo, end: now, options: .strictStartDate)