A small wrapper for sample and statistics queries against HealthKit that is inspired by health library from CACHET.
Add the following entries to your
<key>NSHealthShareUsageDescription</key> <string>Add a reason why you need this.</string> <key>NSHealthUpdateUsageDescription</key> <string>Add a reason why you need this.</string>
- Open your project in Xcode and add "HealthKit" as a capability.
After the setup
Now you can instantiate a HealthStore object:
final store = HealthStore();
Before you query for data make sure, that you ask the user for their permission by calling:
final stepType = HKQuantityType.StepCount.identifier(); final permissionsGranted = await store.requestTypes([stepType]);
Now you can query for the samples. If you query for QuantityTypes you need to provide a tuple of the Type and the unit you want to query for. There is an extension function on the HKQuantityType, so you can do:
final now = DateTime.now(); final samples = await store.getHealthSamplesForQuantityType( start: now.subtract(Duration(days: 2)), end: now, types: [ // manually constructing the tuple HKQuantityTypeUnitTuple(HKQuantityType.StepCount, 'count'), // using the extension HKQuantityType.HeartRate.withUnit('count/min'), ]);
If you are querying for CategoryTypes, you don't pass a unit, therefore the value property of the result contains the enum value of the subtype.[
See SleepAnalysis for example](https://developer.apple.com/documentation/healthkit/hkcategoryvaluesleepanalysis)
Getting statistics data is also very easy. You need to additionally pass an interval, which is used to accumulate the statistics, and achorDate, which is used to determine where to start an interval. At the moment, the
StatisticsInterval is only capable of handling day, hour, and minute intervals.
final now = DateTime.now(); final start = DateTime(now.year, now.month, now.day, 0, 0); final samples = await store.getHealthStatisticsForType( start: start, end: now, interval: StatisticsInterval(hour: 1), anchor: start, types: [ HKQuantityType.StepCount.withUnit('count'), ]);
The resulting statistics object has 4 value fields (sum, avg, min, max). If the HKQuantityType is cumulative, only the sum field will hold a value. If the type is discrete, avg, min, and max will hold a value.
- For valid units see here
Supported Data Types