如何从Apple的Healthkit获取心率数据？

Question

我正在尝试从Healthkit读取心率数据。我无法读取这些数据。我已经浏览了这个链接。

Answer 1

我使用HKSampleQuery从HelathKit读取心率。我从一天开始读到"现在"。我还使用了这个链接
这是我的函数，我通过按一个按钮调用它:

- (void)readHeartRateWithCompletion:(void (^)(NSArray *results, NSError *error))completion {
    //get the heart rates
    NSDate *now = [NSDate date];
    NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
    NSDateComponents *components = [calendar components:NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:now];
    components.hour = 0;
    components.minute = 0;
    components.second = 0;
    NSDate *beginOfDay = [calendar dateFromComponents:components];
    NSPredicate *predicate = [HKQuery predicateForSamplesWithStartDate:beginOfDay endDate:now options:HKQueryOptionStrictStartDate];
    HKSampleType *sampleType = [HKSampleType quantityTypeForIdentifier:HKQuantityTypeIdentifierHeartRate];
    NSSortDescriptor *lastDateDescriptor = [[NSSortDescriptor alloc]
                                            initWithKey:HKSampleSortIdentifierStartDate ascending:YES selector:@selector(localizedStandardCompare:)];
    NSArray *sortDescriptors = @[lastDateDescriptor];
    HKSampleQuery *query = [[HKSampleQuery alloc] initWithSampleType:sampleType predicate:predicate limit:HKObjectQueryNoLimit sortDescriptors:sortDescriptors resultsHandler:^(HKSampleQuery *query, NSArray *results, NSError *error){
        if (!results) {
            NSLog(@"An error occured fetching the user's heartrate. The error was: %@.", error);
            abort();
        }
        dispatch_async(dispatch_get_main_queue(), ^{
            NSMutableArray *arrayHeartRate = [[NSMutableArray alloc]init];
            for (HKQuantitySample *sample in results) {
                double hbpm = [sample.quantity doubleValueForUnit:[HKUnit heartBeatsPerMinuteUnit]];
                [arrayHeartRate addObject:[NSNumber numberWithDouble:hbpm]];
            }
            if (completion != nil) {
                completion(arrayHeartRate, error);
            }
        });
    }];
    [self.healthStore executeQuery:query];
}

下面是获取每分钟心率值的函数:

@implementation HKUnit (HKManager)
+(HKUnit *)heartBeatsPerMinuteUnit{
    return [[HKUnit countUnit]unitDividedByUnit:[HKUnit minuteUnit]];
}
@end

这是我如何调用函数在我的按钮动作，它读取心率，并把它们放入一个UITextView:

- (IBAction)readHeartRateButtonPressed:(id)sender {
    [[GSHealthKitManager sharedManager]readHeartRateWithCompletion:
    ^(NSArray *results, NSError *error) {
        NSString *items = [results componentsJoinedByString:@"n"];
        _heartRateText.text = items;
    }];
} 

希望能有所帮助。