getMeasurement method

@override Future<Measurement> getMeasurement()

Subclasses should implement this method to collect a Measurement.

Can return null if no data is available. Can return an Error measurement if an error occurs.

Implementation

@override
Future<Measurement> getMeasurement() async {
  // get the last mark - if null, go back as specified in history
  DateTime start = samplingConfiguration.lastTime ??
      DateTime.now().subtract(samplingConfiguration.past);
  DateTime end = DateTime.now();

  debug(
      'Collecting app usage - start: ${start.toUtc()}, end: ${end.toUtc()}');
  List<app_usage.AppUsageInfo> infos =
      await app_usage.AppUsage().getAppUsage(start, end);

  Map<String, AppUsageInfo> usage = {};
  for (var info in infos) {
    usage[info.packageName] = AppUsageInfo.fromAppUsageInfo(info);
  }

  return Measurement(
      sensorStartTime: start.microsecondsSinceEpoch,
      sensorEndTime: end.microsecondsSinceEpoch,
      data: AppUsage(start.toUtc(), end.toUtc(), usage));
}