Fix null ref

projects/common-map/src/fm-map/components/aol/gps-location/gps-location.component.ts

@@ -59,9 +59,11 @@ export class GpsLocation  implements OnInit,OnChanges{
   ngOnChanges(changes: SimpleChanges) {
     if (changes.position && this.instance) {
       var p = changes.position.currentValue as Position;
-      this.instance.setPosition(fromLonLat([p.coords.longitude, p.coords.latitude]));
-      this.locationTolerance = p.coords.accuracy;
-      this.recalcLocationTolerance();
+      if(p) {
+        this.instance.setPosition(fromLonLat([p.coords.longitude, p.coords.latitude]));
+        this.locationTolerance = p.coords.accuracy;
+        this.recalcLocationTolerance();  
+      }
     }
     if(changes.heading && this.instance) {
       this.rotate = "rotate(" +   Math.round(changes.heading.currentValue) + " 500 500)";

projects/common-map/src/fm-map/services/geolocation.service.ts

@@ -1,5 +1,5 @@
 import { Injectable } from '@angular/core';
-import { Observer, Observable } from 'rxjs';
+import { Observer, Observable,BehaviorSubject } from 'rxjs';
 
 /**
  * GeolocationService class.
@@ -9,31 +9,26 @@ import { Observer, Observable } from 'rxjs';
 @Injectable()
 export class GeolocationService {
 
-  /**
-   * Tries HTML5 geolocation.
-   *
-   * Wraps the Geolocation API into an observable.
-   *
-   * @return An observable of Position
-   */
-  getCurrentPosition(): Observable<Position> {
-    return Observable.create((observer: Observer<Position>) => {
-      // Invokes getCurrentPosition method of Geolocation API.
-      navigator.geolocation.watchPosition(
-        (position: Position) => {
-          observer.next(position);
-        },
-        (error: PositionError) => {
-          console.debug('Geolocation service: ' + error.message);
-          //observer.error(error);
-        },
-        {
-          enableHighAccuracy: true,
-          timeout: 5000,
-          maximumAge: 0
-        }
-      );
-    });
+  private positionObserver$:BehaviorSubject<Position>  = new BehaviorSubject<Position>(null);
+
+  constructor() {
+    navigator.geolocation.watchPosition(
+      (position: Position) => {
+        this.positionObserver$.next(position);
+      },
+      (error: PositionError) => {
+        console.debug('Geolocation service: ' + error.message);
+      },
+      {
+        enableHighAccuracy: true,
+        timeout: 5000,
+        maximumAge: 0
+      }
+    );
   }
 
+
+  getCurrentPosition(): Observable<Position> {
+    return this.positionObserver$;
+  }
 }