ios - 如何检索一组 HealthKit 记录及其元数据

Question

我正在学习一些关于使用 swift 的 HealthKit 的教程，我正在学习的教程之一是如何从 HealthKit 中检索一些数据，例如体重、高度、年龄。本教程展示了如何为它们检索最近的记录，以下代码展示了:

func readMostRecentSample(sampleType:HKSampleType , completion: ((HKSample!, NSError!) -> Void)!)
{

// 1. Build the Predicate
let past = NSDate.distantPast() as! NSDate
let now   = NSDate()
let mostRecentPredicate = HKQuery.predicateForSamplesWithStartDate(past, endDate:now, options: .None)

// 2. Build the sort descriptor to return the samples in descending order
let sortDescriptor = NSSortDescriptor(key:HKSampleSortIdentifierStartDate, ascending: false)
// 3. we want to limit the number of samples returned by the query to just 1 (the most recent)
let limit = 1

// 4. Build samples query
let sampleQuery = HKSampleQuery(sampleType: sampleType, predicate: mostRecentPredicate, limit: limit, sortDescriptors: [sortDescriptor])
  { (sampleQuery, results, error ) -> Void in

    if let queryError = error {
      completion(nil,error)
      return;
    }

    // Get the first sample
    let mostRecentSample = results.first as? HKQuantitySample

    // Execute the completion closure
    if completion != nil {
      completion(mostRecentSample,nil)
    }
}
// 5. Execute the Query
self.healthKitStore.executeQuery(sampleQuery)
}

然后在其他类中开发者传参获取需要的最新记录，下面代码展示了获取高度记录的方法:

func updateHeight()
{
// 1. Construct an HKSampleType for Height
let sampleType = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierHeight)

// 2. Call the method to read the most recent Height sample
self.healthManager?.readMostRecentSample(sampleType, completion: { (mostRecentHeight, error) -> Void in

  if( error != nil )
  {
    println("Error reading height from HealthKit Store: \(error.localizedDescription)")
    return;
  }

  var heightLocalizedString = self.kUnknownString;
  self.height = mostRecentHeight as? HKQuantitySample;
  // 3. Format the height to display it on the screen
  if let meters = self.height?.quantity.doubleValueForUnit(HKUnit.meterUnit()) {
    let heightFormatter = NSLengthFormatter()
    heightFormatter.forPersonHeightUse = true;
    heightLocalizedString = heightFormatter.stringFromMeters(meters);
  }


  // 4. Update UI. HealthKit use an internal queue. We make sure that we interact with the UI in the main thread
  dispatch_async(dispatch_get_main_queue(), { () -> Void in
    self.heightLabel.text = heightLocalizedString
    self.updateBMI()
  });
})

}

我创建了一个与第一个类似的方法，但几乎没有改动，因此我可以获得一个包含 10 个葡萄糖记录的数组:

func readAllGlucose(sampleType:HKSampleType , completion: (([HKSample!], NSError!) -> Void)!)
{

    let now   = NSDate()
    let df = NSDateFormatter()
    df.dateFormat = "yyyy-MM-dd"
    let pastt = df.dateFromString("2015-05-18")

    //let mostRecentPredicate = HKQuery.predicateForSamplesWithStartDate(past, endDate:now, options: .None)
    let allreadings = HKQuery.predicateForSamplesWithStartDate(pastt, endDate: now, options: .None)

    // 2. Build the sort descriptor to return the samples in descending order
    let sortDescriptor = NSSortDescriptor(key:HKSampleSortIdentifierStartDate, ascending: false)
    // 3. we want to limit the number of samples returned by the query to just 1 (the most recent)
    let limit = 10

    // 4. Build samples query

    let sampleQuery = HKSampleQuery(sampleType: sampleType, predicate: allreadings, limit: limit, sortDescriptors: [sortDescriptor])
        { (sampleQuery, results, error ) -> Void in

            if let queryError = error {
                completion([nil],error)
                return;
            }

            // Get the first sample
            let allSamples = results as? [HKQuantitySample]

            // Execute the completion closure
            if completion != nil {
                completion(allSamples!,nil)
            }
    }
    // 5. Execute the Query
    self.healthKitStore.executeQuery(sampleQuery)
}

然后我创建了另一个类似于 updateHeight() 方法的方法，但当然做了必要的更改:

func updateLastGlucoRecords()
{
    // 1. Construct an HKSampleType for weight
    let sampleType = HKSampleType.quantityTypeForIdentifier(HKQuantityTypeIdentifierBloodGlucose)

    // 2. Call the method to read the most recent weight sample
    self.healthManager?.readAllGlucose(sampleType, completion: {([allReadings], error) -> Void in

        if (error != nil) {
            println("Error reading glucose readings from HealthKit Store: \(error.localizedDescription)")
            return;
        }

        var glucoseLocalizedString = self.kUnknownString;
        self.glucose = allReadings as? [HKQuantitySample]
        for reading in readings {

            if let record = reading.quantity {
                glucoseLocalizedString = record
            }
            dispatch_async(dispatch_get_main_queue(), { () -> Void in
                self.glucoReadings.append("\(glucoseLocalizedString)")
            })

        }


    })
    self.healthManager?.readMostRecentSample(sampleType, completion: { (mostRecentWeight, error) -> Void in

        if( error != nil )
        {
            println("Error reading weight from HealthKit Store: \(error.localizedDescription)")
            return;
        }

        var weightLocalizedString = self.kUnknownString;
        // 3. Format the weight to display it on the screen
        self.weight = mostRecentWeight as? HKQuantitySample;
        if let kilograms = self.weight?.quantity.doubleValueForUnit(HKUnit.gramUnitWithMetricPrefix(.Kilo)) {
            let weightFormatter = NSMassFormatter()
            weightFormatter.forPersonMassUse = true;
            weightLocalizedString = weightFormatter.stringFromKilograms(kilograms)
        }

        // 4. Update UI in the main thread
        dispatch_async(dispatch_get_main_queue(), { () -> Void in
            self.weightLabel.text = weightLocalizedString
            self.updateBMI()

        });
    });
}

但不幸的是，我在行中遇到了两个错误:

self.healthManager?.readAllGlucose(sampleType, completion: {([allReadings], error) -> Void in

第一个错误:

[HKSample!]' is not a subtype of '<>

第二个错误:

Use of undeclared type 'allReadings'

我还有一个问题，如何从每个对象中获取元数据，我想获取插入数据的日期和时间

如果有人有任何想法可以解决这个问题，我将不胜感激

提前致谢

Answer 1

我遇到了同样的问题。请在下面查看我的代码。1.) allReadings 错误是由于您没有传递 HKSample 数组的原因，所以要创建它，您必须这样写:let allReadings:[HKSample!] 然后传递 allReadings。

func readAllSample(sampleType:HKSampleType , completion: (([HKSample!], NSError!) -> Void)!)
{
    let now   = NSDate()
    let past = now.dateByAddingTimeInterval(-10*24*60*60) as NSDate!
    let mostRecentPredicate = HKQuery.predicateForSamplesWithStartDate(past, endDate:now, options: .None)
    let sortDescriptor = NSSortDescriptor(key:HKSampleSortIdentifierStartDate, ascending: false)
    let limit = 10
    let sampleQuery = HKSampleQuery(sampleType: sampleType, predicate: mostRecentPredicate, limit: limit, sortDescriptors: [sortDescriptor])
        { (sampleQuery, results, error ) -> Void in

            if(error == nil)
            {
                print(results)
            }

    }
    self.healthKitStore.executeQuery(sampleQuery)
}