我正在尝试获取过去一个月的所有心率样本,并从中提取时间和值。
到目前为止,我有以下方法:
func getThisMonthsHeartRates() {
print("func called")
let heartRateUnit:HKUnit = HKUnit(from: "count/min")
let heartRateType:HKQuantityType = HKQuantityType.quantityType(forIdentifier: .heartRate)!
//predicate
let startDate = Date()
let endDate = Date() - 1.month
let predicate = HKQuery.predicateForSamples(withStart: startDate, end: endDate, options: [])
//descriptor
let sortDescriptors = [
NSSortDescriptor(key: HKSampleSortIdentifierEndDate, ascending: false)
]
let heartRateQuery = HKSampleQuery(sampleType: heartRateType,
predicate: predicate,
limit: Int(HKObjectQueryNoLimit),
sortDescriptors: sortDescriptors)
{ (query:HKSampleQuery, results:[HKSample]?, error:Error?) -> Void in
guard error == nil else { print("error"); return }
print("results")
print(results!)
for result in results! {
guard let currData:HKQuantitySample = result as? HKQuantitySample else { return }
print("Heart Rate: \(currData.quantity.doubleValue(for: heartRateUnit))")
print("quantityType: \(currData.quantityType)")
print("Start Date: \(currData.startDate)")
print("End Date: \(currData.endDate)")
print("Metadata: \(String(describing: currData.metadata))")
print("UUID: \(currData.uuid)")
print("Source: \(currData.sourceRevision)")
print("Device: \(String(describing: currData.device))")
print("---------------------------------\n")
}
} //eo-query
healthStore.execute(heartRateQuery)
}//eom
然而,结果总是会返回一个空数组,即使我的设备上有样本!真的很好奇这是怎么回事以及如何解决它。我完全不知所措。
谢谢
更新
在执行查询之前和执行期间记录查询后,控制台会这样说:
<HKSampleQuery:0x1c4117610 inactive>
和
<HKSampleQuery:0x1c4117610 deactivated>
我不知道这意味着什么,也无法在网上找到任何关于它的信息。