However impressive a created display is it is unlikely to hold the user's attention forever and they are likely to switch to another application or browser tab. Luckily, HTML5 has a feature that will allow notifications on the desktop.

The main.dart function quakeUpdate checks if there is a significant update to notify the user about. To determine which item in the list to notify the user about, the lastWhere method is used. This List method finds the last item in the list that matches the criteria defined by the supplied function. In this case, we look at each feature's magnitude value (stored in gf[2]) and return true or false if the value meets the threshold:

quakeUpdate([Timer t = null]) async {
  await featPlotter.updateData();
  featPlotter.updateHotspots();
  quakeMap.drawMapGrid();

  List notiFeature =
      featPlotter.geoFeatures.lastWhere((List gf) => gf[2] > 1.9);

  String permResult = await Notification.requestPermission();
  if (permResult...