if(fromClick) { this.subscription.off(); this.firstRun = true;}
this.postFeed = new Array();
this.subscription = this.database.database.ref('/posts/'+this.locationId)
   .orderByChild('created')
   .limitToLast(10);

this.subscription.on('child_added', (snapshot) => {
   this.postFeed.push(snapshot.val());
});