observerQuery static method
Sets subscription for data changes.
Will call onUpdate
callback, if
there were changes regarding to the provided identifier
inside HealthKit
.
Provide the predicate
to set the date interval.
Implementation
static StreamSubscription<dynamic> observerQuery(
List<String> identifiers, Predicate? predicate,
{required Function(String) onUpdate}) {
final arguments = <String, dynamic>{
'identifiers': identifiers,
};
if (predicate != null) {
arguments.addAll(predicate.map);
}
return _observerQueryChannel
.receiveBroadcastStream(arguments)
.listen((event) {
final map = Map<String, dynamic>.from(event);
final identifier = map['identifier'];
onUpdate(identifier);
});
}