clean up BackgroundGeolocation configuration and start/stop (#412)

LocationService.js
- Clean up variable name for internal configuration, and when it's set.
- remove unused variable from .stop() method

LocationTracking.js
- Moved LocationService start() and stop() calls to ensure the location service gets enabled or disabled appropriately if a user changes location permissions

app/services/LocationService.js

@@ -7,7 +7,7 @@ import PushNotification from 'react-native-push-notification';
 import { isPlatformAndroid } from '../Util';
 import languages from '../locales/languages';
 
-let hasBeenStarted = false;
+let isBackgroundGeolocationConfigured = false;
 
 export class LocationData {
   constructor() {
@@ -133,11 +133,10 @@ export default class LocationServices {
 
     // handles edge cases around Android where start might get called again even though
     // the service is already created.  Make sure the listeners are still bound and exit
-    if (hasBeenStarted) {
+    if (isBackgroundGeolocationConfigured) {
       BackgroundGeolocation.start();
       return;
     }
-    hasBeenStarted = true;
 
     PushNotification.configure({
       // (required) Called when a remote or local notification is opened or received
@@ -291,6 +290,7 @@ export default class LocationServices {
       );
 
       BackgroundGeolocation.start(); //triggers start on start event
+      isBackgroundGeolocationConfigured = true;
 
       if (!status.locationServicesEnabled) {
         // we need to set delay or otherwise alert may not be shown
@@ -345,15 +345,15 @@ export default class LocationServices {
     });
   }
 
-  static stop(nav) {
+  static stop() {
     // unregister all event listeners
     PushNotification.localNotification({
       title: languages.t('label.location_disabled_title'),
       message: languages.t('label.location_disabled_message'),
     });
     BackgroundGeolocation.removeAllListeners();
     BackgroundGeolocation.stop();
-    instanceCount -= 1;
+    isBackgroundGeolocationConfigured = false;
     SetStoreData('PARTICIPATE', 'false').then(() => {
       // nav.navigate('LocationTrackingScreen', {});
     });

app/views/LocationTracking.js

@@ -111,11 +111,13 @@ class LocationTracking extends Component {
       .then(result => {
         switch (result) {
           case RESULTS.GRANTED:
+            LocationServices.start();
             this.checkIfUserAtRisk();
             return;
           case RESULTS.UNAVAILABLE:
           case RESULTS.BLOCKED:
             console.log('NO LOCATION');
+            LocationServices.stop();
             this.setState({ currentState: StateEnum.UNKNOWN });
         }
       })
@@ -293,21 +295,20 @@ class LocationTracking extends Component {
 
   willParticipate = () => {
     SetStoreData('PARTICIPATE', 'true').then(() => {
-      LocationServices.start();
-      // Turn of bluetooth for v1
+      // Turn off bluetooth for v1
       //BroadcastingServices.start();
     });
-
     // Check and see if they actually authorized in the system dialog.
     // If not, stop services and set the state to !isLogging
     // Fixes tripleblindmarket/private-kit#129
     BackgroundGeolocation.checkStatus(({ authorization }) => {
       if (authorization === BackgroundGeolocation.AUTHORIZED) {
+        LocationServices.start();
         this.setState({
           isLogging: true,
         });
       } else if (authorization === BackgroundGeolocation.NOT_AUTHORIZED) {
-        LocationServices.stop(this.props.navigation);
+        LocationServices.stop();
         // Turn of bluetooth for v1
         //BroadcastingServices.stop(this.props.navigation);
         this.setState({