flutter_background_geolocation 4.16.4

The most sophisticated background location tracking & geofencing module with battery-conscious motion-detection intelligence for iOS and Android.

example/lib/main.dart

import 'package:flutter/material.dart';

import 'package:shared_preferences/shared_preferences.dart';
import 'package:flutter_background_geolocation/flutter_background_geolocation.dart'
    as bg;
import 'package:background_fetch/background_fetch.dart';

import 'package:flutter_background_geolocation_example/app.dart';
import 'advanced/app.dart';
import 'hello_world/app.dart';

import 'config/transistor_auth.dart';
import 'config/env.dart';

/// Receive events from BackgroundGeolocation in Headless state.
@pragma('vm:entry-point')
void backgroundGeolocationHeadlessTask(bg.HeadlessEvent headlessEvent) async {
  print('📬 --> $headlessEvent');

  switch (headlessEvent.name) {
    case bg.Event.BOOT:
      bg.State state = await bg.BackgroundGeolocation.state;
      print("📬 didDeviceReboot: ${state.didDeviceReboot}");
      break;
    case bg.Event.TERMINATE:
      bg.State state = await bg.BackgroundGeolocation.state;
      if (state.stopOnTerminate!) {
        // Don't request getCurrentPosition when stopOnTerminate: true
        return;
      }
      try {
        bg.Location location =
            await bg.BackgroundGeolocation.getCurrentPosition(
                samples: 1,
                persist: true,
                extras: {
                  "event": "terminate",
                  "headless": true
                }
            );
        print("[getCurrentPosition] Headless: $location");
      } catch (error) {
        print("[getCurrentPosition] Headless ERROR: $error");
      }

      break;
    case bg.Event.HEARTBEAT:
      try {
        bg.Location location = await bg.BackgroundGeolocation.getCurrentPosition(
          samples: 2,
          timeout: 10,
          extras: {
            "event": "heartbeat",
            "headless": true
          }
        );

        print('[getCurrentPosition] Headless: $location');
      } catch (error) {
        print('[getCurrentPosition] Headless ERROR: $error');
      }
      break;
    case bg.Event.LOCATION:
      bg.Location location = headlessEvent.event;
      print(location);
      break;
    case bg.Event.MOTIONCHANGE:
      bg.Location location = headlessEvent.event;
      print(location);
      break;
    case bg.Event.GEOFENCE:
      bg.GeofenceEvent geofenceEvent = headlessEvent.event;
      print(geofenceEvent);
      break;
    case bg.Event.GEOFENCESCHANGE:
      bg.GeofencesChangeEvent event = headlessEvent.event;
      print(event);
      break;
    case bg.Event.SCHEDULE:
      bg.State state = headlessEvent.event;
      print(state);
      break;
    case bg.Event.ACTIVITYCHANGE:
      bg.ActivityChangeEvent event = headlessEvent.event;
      print(event);
      break;
    case bg.Event.HTTP:
      bg.HttpEvent response = headlessEvent.event;
      print(response);
      break;
    case bg.Event.POWERSAVECHANGE:
      bool enabled = headlessEvent.event;
      print(enabled);
      break;
    case bg.Event.CONNECTIVITYCHANGE:
      bg.ConnectivityChangeEvent event = headlessEvent.event;
      print(event);
      break;
    case bg.Event.ENABLEDCHANGE:
      bool enabled = headlessEvent.event;
      print(enabled);
      break;
    case bg.Event.AUTHORIZATION:
      bg.AuthorizationEvent event = headlessEvent.event;
      print(event);
      bg.BackgroundGeolocation.setConfig(
          bg.Config(url: "${ENV.TRACKER_HOST}/api/locations"));
      break;
  }
}

/// Receive events from BackgroundFetch in Headless state.
@pragma('vm:entry-point')
void backgroundFetchHeadlessTask(HeadlessTask task) async {
  String taskId = task.taskId;

  // Is this a background_fetch timeout event?  If so, simply #finish and bail-out.
  if (task.timeout) {
    print("[BackgroundFetch] HeadlessTask TIMEOUT: $taskId");
    BackgroundFetch.finish(taskId);
    return;
  }

  print("[BackgroundFetch] HeadlessTask: $taskId");

  try {
    var location = await bg.BackgroundGeolocation.getCurrentPosition(
	    samples: 2,
      extras: {
        "event": "background-fetch",
        "headless": true
      }
    );
    print("[location] $location");
  } catch(error) {
    print("[location] ERROR: $error");
  }

  SharedPreferences prefs = await SharedPreferences.getInstance();
  int count = 0;
  if (prefs.get("fetch-count") != null) {
    count = prefs.getInt("fetch-count")!;
  }
  prefs.setInt("fetch-count", ++count);
  print('[BackgroundFetch] count: $count');

  BackgroundFetch.finish(taskId);
}

void main() {
  WidgetsFlutterBinding.ensureInitialized();

  /// Application selection:  Select the app to boot:
  /// - AdvancedApp
  /// - HelloWorldAp
  /// - HomeApp
  ///
  SharedPreferences.getInstance().then((SharedPreferences prefs) {
    String? appName = prefs.getString("app");

    // Sanitize old-style registration system that only required username.
    // If we find a valid username but null orgname, reverse them.
    String? orgname = prefs.getString("orgname");
    String? username = prefs.getString("username");

    if (orgname == null && username != null) {
      prefs.setString("orgname", username);
      prefs.remove("username");
    }

    switch (appName) {
      case AdvancedApp.NAME:
        runApp(new AdvancedApp());
        break;
      case HelloWorldApp.NAME:
        runApp(new HelloWorldApp());
        break;
      default:
        // Default app.  Renders the application selector home page.
        runApp(new HomeApp());
    }
  });
  TransistorAuth.registerErrorHandler();

  /// Register BackgroundGeolocation headless-task.
  bg.BackgroundGeolocation.registerHeadlessTask(
      backgroundGeolocationHeadlessTask);

  /// Register BackgroundFetch headless-task.
  BackgroundFetch.registerHeadlessTask(backgroundFetchHeadlessTask);
}