HealthKit Swift getting today's steps

Question

I am making a swift iOS app that integrates with a user\'s step count as reported by the Health app. I can easily find the user\'s step count in the last hour, using this as

Answer 1

Using the above answers and from Apple here: https://developer.apple.com/reference/healthkit/hkstatisticsquery I got the following to work in swift 2.3 on Xcode 8.0.

class func getStepCountHealth(startDate: NSDate, endDate: NSDate, completion:(Double?, NSError?)->()) {

            let healthKitStore:HKHealthStore = HKHealthStore()

            //   Define the sample type
            let sampleType = HKQuantityType.quantityTypeForIdentifier(
            HKQuantityTypeIdentifierStepCount)

            //  Set the predicate
            let predicate = HKQuery.predicateForSamplesWithStartDate(startDate,
                                                                 endDate: endDate, options: .None)
            // build the query
            let sampleQuery = HKStatisticsQuery(quantityType: sampleType!,
                                      quantitySamplePredicate: predicate,
                                      options: .CumulativeSum) { query, results, error in

                                        if results != nil {
                                            let quantity = results?.sumQuantity()
                                            let unit = HKUnit.countUnit()
                                            let totalSteps = quantity?.doubleValueForUnit(unit)
                                            completion(totalSteps, error)
//                                            print("totalSteps for \(endDate) are \(totalSteps!)")
                                        } else {
                                            completion(nil, error)
//                                            print("results are nil")
                                            return
                                        } 
                                    }
            // execute the Query
            healthKitStore.executeQuery(sampleQuery)
        }