Reference Array in Different Class Swift - ios

So I have this function, which gets and prints all the HealthKit step data from the past 24 hours, and saves it to an array:
func stepsInPastDay(completion: (Double, NSError?) -> () )
{
var dayStepData = [Double]()
for x in 1...24 {
// The type of data we are requesting
let type = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
var hoursAgo = -1 * x
var hoursSince = (-1 * x) + 1
// Our search predicate which will fetch data from now until a day ago
let predicate = HKQuery.predicateForSamplesWithStartDate(NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitHour, value: hoursAgo, toDate: NSDate(), options: nil), endDate: NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitHour, value: hoursSince, toDate: NSDate(), options: nil), options: .None)
// The actual HealthKit Query which will fetch all of the steps and sub them up for us.
let query = HKSampleQuery(sampleType: type, predicate: predicate, limit: 0, sortDescriptors: nil) { query, results, error in
var steps: Double = 0
if results?.count > 0
{
for result in results as! [HKQuantitySample]
{
steps += result.quantity.doubleValueForUnit(HKUnit.countUnit())
}
}
completion(steps, error)
dayStepData.append(steps)
if dayStepData.count > 23 {
for item in dayStepData {
println(item)
}
}
}
self.healthKitStore.executeQuery(query)
println(dayStepData.count)
}
println(dayStepData.count)
}
However, when I tried to access the array (dayStepData) in my AppDelegate file, with "HKManager.stepsInPastDay.dayStepData" (HKManager is the class), Xcode returns an error. Is there a way to get the array from my function?

This is OOP (Object-oriented-programmming) 101 stuff. You are saving your value to a local variable. Of course it isn't visible in your app delegate.
Put the function in a singleton class of some sort make the function return the array as the function result.
If you're putting app logic in your app delegate you're doing it wrong. Keep your app delegate small and lightweight. It should ONLY handle startup and other app delegate tasks. Put your app-specific logic in other modules.

Related

How to only query HealthKit for Total "In Bed" time for a given day?

There isn't a whole of sample code on the internet for querying for sleep data. The below code will return all sleep samples from a given day which if you look at the Apple Health App include "Asleep" samples from the Apple Watch which are sleep intervals, but there is also an "In Bed" sample from the iPhone which contains the total range from getting in bed to getting out of bed. How can I query HealthKit for only this In Bed sample?
func sleepTime() {
let healthStore = HKHealthStore()
// startDate and endDate are NSDate objects
// first, we define the object type we want
if let sleepType = HKObjectType.categoryType(forIdentifier: HKCategoryTypeIdentifier.sleepAnalysis) {
// You may want to use a predicate to filter the data... startDate and endDate are NSDate objects corresponding to the time range that you want to retrieve
//let predicate = HKQuery.predicateForSamplesWithStartDate(startDate,endDate: endDate ,options: .None)
// Get the recent data first
let sortDescriptor = NSSortDescriptor(key: HKSampleSortIdentifierEndDate, ascending: false)
// the block completion to execute
let query = HKSampleQuery(sampleType: sleepType, predicate: nil, limit: 100000, sortDescriptors: [sortDescriptor]) { (query, tmpResult, error) -> Void in
if error != nil {
// Handle the error in your app gracefully
return
}
if let result = tmpResult {
for item in result {
if let sample = item as? HKCategorySample {
let startDate = sample.startDate
let endDate = sample.endDate
print()
let sleepTimeForOneDay = sample.endDate.timeIntervalSince(sample.startDate)
}
}
}
}
}
HKCategorySample contains the value of type Int which is the enumeration value for the sample.
It has three values:
0 -> inBed
1 -> asleep
2 -> awake
So, the proposed change if you only want inBed data is:
if let result = tmpResult {
for item in result {
if let sample = item as? HKCategorySample {
if sample.value == 0 {
let startDate = sample.startDate
let endDate = sample.endDate
print()
let sleepTimeForOneDay = sample.endDate.timeIntervalSince(sample.startDate)
}
}
}
}
Better way is to go with switch case.
if let result = tmpResult {
for item in result {
if let sample = item as? HKCategorySample {
switch sample.value {
case 0:
// inBed, write logic here
print("inBed")
case 1:
// asleep, write logic here
print("asleep")
default:
// awake, write logic here
print("awake")
}
}
}
}

How to return result of HKStatisticsQuery to a variable in Swift 2?

UPDATED at bottom on 01/30/16 # 7:40PM EST
So I'm trying to run a StatisticsQuery to get the total DistanceRunningWalking of the day stored in HealthKit and then store the results of that query in a variable, to be worked with later. The query seems to be working fine, as I've tested printing the results of the query (totalDistance) to a Label from within the function. The problem I'm running into is when trying to save the result to a variable instead.
Here is the code in my HealthKitManager.swift file:
import HealthKit
class HealthKitManager {
class var sharedInstance: HealthKitManager {
struct Singleton {
static let instance = HealthKitManager()
}
return Singleton.instance
}
let healthStore: HKHealthStore? = {
if HKHealthStore.isHealthDataAvailable() {
return HKHealthStore()
} else {
return nil
}
}()
let distanceCount = HKQuantityType.quantityTypeForIdentifier(HKQuantityTypeIdentifierDistanceWalkingRunning)
let distanceUnit = HKUnit(fromString: "mi")
}
Code at top of ViewController: (this is the variable I'd like to save to)
let healthKitManager = HealthKitManager.sharedInstance
//Set up variable to contain result of query
var distanceTotalLength:Double?
Code in viewDidLoad:
//Run the function
requestHealthKitAuthorization()
//Set value of variable to query result
distanceTotalLength = queryDistanceSum()
Code in body of ViewController:
func requestHealthKitAuthorization() {
let dataTypesToRead = NSSet(objects: healthKitManager.distanceCount!)
healthKitManager.healthStore?.requestAuthorizationToShareTypes(nil, readTypes: dataTypesToRead as NSSet as? Set<HKObjectType>, completion: { [unowned self] (success, error) in
if success {
self.queryDistanceSum()
} else {
print(error!.description)
}
})
}
func queryDistanceSum() {
let sumOption = HKStatisticsOptions.CumulativeSum
let startDate = NSDate().dateByRemovingTime()
let endDate = NSDate()
let predicate = HKQuery.predicateForSamplesWithStartDate(startDate, endDate: endDate, options: [])
let statisticsSumQuery = HKStatisticsQuery(quantityType: healthKitManager.distanceCount!, quantitySamplePredicate: predicate, options: sumOption) {
[unowned self] (query, result, error) in
if let sumQuantity = result?.sumQuantity() {
dispatch_async(dispatch_get_main_queue(), {
let totalDistance = sumQuantity.doubleValueForUnit(self.healthKitManager.distanceUnit)
self.distanceTotalLength = totalDistance
})
}
}
healthKitManager.healthStore?.executeQuery(statisticsSumQuery)
}
On the last line return (distanceTotalLength)! I'm getting an error when launching the application which reads fatal error: unexpectedly found nil while unwrapping an Optional value. I've realized that this is most likely a problem dealing with scope (although I may be doing something else wrong, so please point anything out) but I'm failing to see/find the solution to the issue on my own.
Any help with this would be greatly appreciated, so thanks in advance!
UPDATE: 01/30/16 # ~7:40PM EST
Okay, so I've been working on trying to fix this myself and I've made a discovery: The code is definitely working. By assigning an initial value of 0 to distanceTotalLength at the top of the ViewController, I was able to run the application without getting the fatal error. However, when I then tried passing the value of distanceTotalLength to another view via a prepareForSegue function, I realized that it is being assigned after all. When I go to that view, it isn't using the initial value of 0, but the result of the query instead.
The way I tested this out was by setting up the variable: var distanceTotalLength:Double = 0 at the very top of my viewController, before viewDidLoad Then inside viewDidLoad I assigned the value to a label using distanceLabel.text = String(distanceTotalLength) and as I said, the label ends up reading 0. But when I transition to another view, passing the value of distanceTotalLength and printing the value out there, it works. On this second screen, it prints the result of the query, not 0.
So I'm assuming that the problem is that the query runs and then assigns the value AFTER the view has already loaded in with all of it's predefined values. Unfortunately, this is where I get stuck again. Anyone out there know how to help me out now that I've gotten this far?
You are right. The completionHandler closure that gets called after your HKStatisticsQuery has finished executing happens at an undermined later time. Think of the query execution as sending a letter in the mail to someone, then waiting for their response; it's not going to be immediate, but in the meantime you can go off and do other things.
To handle this in your code, add a completion closure of your own to the queryDistanceSum method. Then after setting the self.distanceTotalLength = totalDistance, call that closure. When implementing the code for the closure, add anything that needs to be done after the distance has been set, like update your UI.
func queryDistanceSum(completion: () -> Void) { // <----- add the closure here
let sumOption = HKStatisticsOptions.CumulativeSum
let startDate = NSDate().dateByRemovingTime()
let endDate = NSDate()
let predicate = HKQuery.predicateForSamplesWithStartDate(startDate, endDate: endDate, options: [])
let statisticsSumQuery = HKStatisticsQuery(quantityType: healthKitManager.distanceCount!, quantitySamplePredicate: predicate, options: sumOption) {
[unowned self] (query, result, error) in
if let sumQuantity = result?.sumQuantity() {
dispatch_async(dispatch_get_main_queue(), {
let totalDistance = sumQuantity.doubleValueForUnit(self.healthKitManager.distanceUnit)
self.distanceTotalLength = totalDistance
completion() // <----- call the closure here
})
}
}
healthKitManager.healthStore?.executeQuery(statisticsSumQuery)
}
// Then whenever you need to update the distance sum call the function
// with the closure, then handle the result as needed
queryDistanceSum { () -> () in
// distanceTotalLength has now been set.
// Update UI for new distance value or whatever you need to do
}
Whenever you implement a closure you have to assume that the code in the closure will be executed at a later time.

How to Wait for Asynchronous Function Swift

I have a function that gathers step data, but I need a way to make it wait for its query to finish before it loops. I realize there are other questions about this problem, but I can't figure out how to fix it. The function is below:
func stepsAllTime(completion: (Double, NSError?) -> () ) {
var stopStart = true
while stopStart {
x += -1
// The type of data we are requesting
let sampleType = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
var daysAgo = x
var daysSince = x + 1
var daysSinceNow = -1 * daysAgo
checker = allTimeSteps.count
// Our search predicate which will fetch data from now until a day ago
let samplePredicate = HKQuery.predicateForSamplesWithStartDate(NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitDay, value: daysAgo, toDate: NSDate(), options: nil), endDate: NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitDay, value: daysSince, toDate: NSDate(), options: nil), options: .None)
// The actual HealthKit Query which will fetch all of the steps and sub them up for us.
let stepQuery = HKSampleQuery(sampleType: sampleType, predicate: samplePredicate, limit: 0, sortDescriptors: nil) { query, results, error in
var steps: Double = 0
if results?.count > 0 {
for result in results as! [HKQuantitySample] {
steps += result.quantity.doubleValueForUnit(HKUnit.countUnit())
}
}
completion(steps, error)
self.allTimeStepsSum += steps
self.allTimeSteps.append(steps)
println("New Sum:")
println(self.allTimeStepsSum)
println("Days Since Today:")
println(daysSinceNow)
if !(self.allTimeStepsTotal > self.allTimeStepsSum) {
stopStart = false
}
}
if allTimeStepsTotal > allTimeStepsSum {
self.healthKitStore.executeQuery(stepQuery)
}
}
}
How can this be done? Is there some sort of "On Complete" function in Swift?
I'm assuming that my comment was accurate.
You'd probably want to take a look at a recursive pattern, something like this:
import HealthKit
class Person {
var nbSteps: Double = 0
func fetchInfo() -> Void {
let sampleType = HKSampleType()
let samplePredicate: NSPredicate? = nil // Your predicate
let stepQuery = HKSampleQuery(
sampleType: sampleType,
predicate: samplePredicate,
limit: 0,
sortDescriptors: nil) { (sampleQuery, object, error) -> Void in
self.nbSteps += 1 // or the value you're looking to add
dispatch_async(dispatch_get_main_queue(), { () -> Void in // Dispatch in order to keep things clean
self.fetchInfo()
})
}
}
}
You can make the program to wait till the query finishes by implementing callbacks.
You can read more about it in the following blog post
http://www.charles-socrates-chandler.com/blog/2015/2/10/callbacks-in-swift

Step Count Function skipping lines Swift

I have a function that takes the total number of steps recorded by the device, saves it to a variable, and then gets the step data from each day, adding them to another variable until the two have the same value. I need this in order to for the app to know when to stop when it is saving the all time step data to an array.
However, the second half of this function does not execute, and I have no idea why. Here is the function:
// allTimeStepTotal and allTimeStepSum are doubles that are defined with a value of 0.0
func stepsAllTime(completion: (Double, NSError?) -> () ) {
// The type of data we are requesting
let type = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
// Our search predicate which will fetch data from now until a day ago
let predicate = HKQuery.predicateForSamplesWithStartDate(NSDate.distantPast() as! NSDate, endDate: NSDate(), options: .None)
// The actual HealthKit Query which will fetch all of the steps and sub them up for us.
let query = HKSampleQuery(sampleType: type, predicate: predicate, limit: 0, sortDescriptors: nil) { query, results, error in
var steps: Double = 0
if results?.count > 0 {
for result in results as! [HKQuantitySample] {
steps += result.quantity.doubleValueForUnit(HKUnit.countUnit())
}
}
completion(steps, error)
self.allTimeStepsTotal += steps
println("Total:")
println(self.allTimeStepsTotal)
println("Sum:")
println(self.allTimeStepsSum)
}
self.healthKitStore.executeQuery(query)
println("Moving On")
var x = 1
while self.allTimeStepsTotal > self.allTimeStepsSum {
x += -1
// The type of data we are requesting
let sampleType = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
var daysAgo = -1 * x
var daysSince = (-1 * x) + 1
// Our search predicate which will fetch data from now until a day ago
let samplePredicate = HKQuery.predicateForSamplesWithStartDate(NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitDay, value: daysAgo, toDate: NSDate(), options: nil), endDate: NSCalendar.currentCalendar().dateByAddingUnit(.CalendarUnitDay, value: daysSince, toDate: NSDate(), options: nil), options: .None)
// The actual HealthKit Query which will fetch all of the steps and sub them up for us.
let stepQuery = HKSampleQuery(sampleType: sampleType, predicate: samplePredicate, limit: 0, sortDescriptors: nil) { query, results, error in
var steps: Double = 0
if results?.count > 0 {
for result in results as! [HKQuantitySample] {
steps += result.quantity.doubleValueForUnit(HKUnit.countUnit())
}
}
completion(steps, error)
self.allTimeStepsSum += steps
println("New Sum:")
println(self.allTimeStepsSum)
}
self.healthKitStore.executeQuery(stepQuery)
}
And here is the call:
healthManager.stepsAllTime({Double, NSError in
println("All Done")
})
println("Finished executing stepsAllTime")
Can anyone tell me what I need to fix, or what went wrong?
Assuming that allTimeStepsTotal and allTimeStepsSum are initialized to 0.0, the second half of that function won't execute because the HKSampleQuery you've created executes asynchronously—that is, it calls the resultHandler at some time in the future after the the while loop in the second half of your function is evaluated. The condition self.allTimeStepsTotal > self.allTimeStepsSum will evaluate to false since both values are still 0.0, and the loop will not execute.

How can I return all values as NSArray? from query in completion block

In QueryHK I run a HealthKit query for steps and the corresponding date. I return the values in a completion handler. In ViewController I declare the completion. My problem is that the method only returns the last value from the iteration sample in samples.
Question: I want all of the data returned in the completion, not just the last value.. How can I return all the data from the query in an NSArray ?
QueryHK.swift:
import UIKit
import HealthKit
class QueryHK: NSObject {
var steps = Double()
var date = NSDate()
func performHKQuery (completion: (steps: Double, date: NSDate) -> Void){
let healthKitManager = HealthKitManager.sharedInstance
let stepsSample = HKQuantityType.quantityTypeForIdentifier(HKQuantityTypeIdentifierStepCount)
let stepsUnit = HKUnit.countUnit()
let sampleQuery = HKSampleQuery(
sampleType: stepsSample,
predicate: nil,
limit: 0,
sortDescriptors: nil)
{
(sampleQuery, samples, error) in
for sample in samples as [HKQuantitySample]
{
self.steps = sample.quantity.doubleValueForUnit(stepsUnit)
self.date = sample.startDate
}
// Calling the completion handler with the results here
completion(steps: self.steps, date: self.date)
}
healthKitManager.healthStore.executeQuery(sampleQuery)
}
}
ViewController:
import UIKit
class ViewController: UIViewController {
var dt = NSDate()
var stp = Double()
var query = QueryHK()
override func viewDidLoad() {
super.viewDidLoad()
printStepsAndDate()
}
func printStepsAndDate() {
query.performHKQuery() {
(steps, date) in
self.stp = steps
self.dt = date
println(self.stp)
println(self.dt)
}
}
}
Have your completion handler receive an array of steps/date pairs:
completion: ([(steps: Double, date: NSDate)]) -> Void
(you could pass two arrays, one of steps and one of dates, but I feel like it’s clearer to pass an array of pairs since the two are tied together)
Then build an array of pairs of step counts and dates:
if let samples = samples as? [HKQuantitySample] {
let steps = samples.map { (sample: HKQuantitySample)->(steps: Double, date: NSDate) in
let stepCount = sample.quantity.doubleValueForUnit(stepsUnit)
let date = sample.startDate
return (steps: stepCount, date: date)
}
completion(steps)
}
If you want the query class to retain this information as well, make the member variable an array of the same type and store the result in that as well as pass it to the callback.

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