Problems with onQueryEvent observable failing upon routing in Nativescript with Angular - firebase

Question

I am using Nativescript with Angular and have code written that succesfully calls an onQueryEvent from the nativescript-firebase-plugin for data set upon first building the application. However after following a route to a second component containing the exact same onQueryEvent the data succeeds to retreive a complete list but skips the onQueryEvent.
In all honesty I don't know best practices for queries in any situation let alone this one, so I hope it is just a matter of manipulating how I call the onQueryEvent.
I believe the problem to be in the firebase.query inside the getMyTransactionList() function of the firebase.service.ts file.
the overview.component.html page has a transaction | async RadListView that successfully filters upon running tns run android. Then clicking any link directing to the deal-summary.component.html page where the function is re-iterated refuses to query by the static storage variable set in the firebase.service
Here is my code:
firebase.service.ts
export class FirebaseService {
private _allItems: Array<any> = [];
items: BehaviorSubject<Array<any>> = new BehaviorSubject([]);
public storage: any = '-KomUSGcX-j6qQmY4Wrh'; // set statically to test different routes
constructor(
private ngZone: NgZone,
){}
// fetch data
getMyDealList(): Observable<any> {
return new Observable((observer: any) => {
let path = `deals/${BackendService.token}`;
let onValueEvent = (snapshot: any) => {
this.ngZone.run(() => {
let results = this.handleSnapshot(snapshot.value);
observer.next(results);
});
};
firebase.addValueEventListener(onValueEvent, `/${path}`);
}).share();
}
getMyTransactionList(): Observable<any> {
return new Observable((observer: any) => {
let path = `transactions/${BackendService.token}`;
// this is a merge of jen loopers giftler code combined with nativescrip-firebase-plugins standard onQueryEvent. It works on the first load but routing to a second instance of the same function retrieves all the data without queryEvent
let onQueryEvent = (snapshot: any) => {
this.ngZone.run(() => {
let results = this.handleSnapshot(snapshot.value);
observer.next(results);
});
};
firebase.query(
onQueryEvent,
`/transactions/${BackendService.token}`,
{
singleEvent: true,
orderBy: {
type: firebase.QueryOrderByType.CHILD,
value: 'dealId' // mandatory when type is 'child'
},
range:
{
type: firebase.QueryRangeType.EQUAL_TO,
value: `${this.storage}` // this calls a static variable for testing consistency
}
,
}
);
firebase.addValueEventListener(onQueryEvent, `/${path}`);
console.log("transaction Listener added");
}).share();
}
handleSnapshot(data: any) {
//empty array, then refill and filter
this._allItems = [];
if (data) {
for (let id in data) {
let result = (<any>Object).assign({id: id}, data[id]);
this._allItems.push(result);
}
this.publishUpdates();
}
return this._allItems;
}
publishUpdates() {
// here, we sort must emit a *new* value (immutability!)
this._allItems.sort(function(a, b){
if(a.date < b.date) return -1;
if(a.date > b.date) return 1;
return 0;
})
this.items.next([...this._allItems]);
}
}
app.component.ts
<page-router-outlet></page-router-outlet>
overview.component.ts
export class OverviewComponent implements OnInit {
public deals: Observable<any>;
public transactions: Observable<any>;
constructor(private router: Router,
private firebaseS: FirebaseService,
){ }
ngOnInit() {
this.deals = <any>this.firebaseS.getMyDealList();
this.transactions = <any>this.firebaseS.getMyTransactionList();
}
viewDealSumm(id){
this.router.navigate(['dashboard/deal-summary', id]);
}
}
overview.component.html
<RadListView [items]="deals | async ">
<ng-template tkListItemTemplate let-item="item">
<StackLayout (tap)="viewDealSumm(item.id)">
<Label [text]="item.dealName"></Label>
</StackLayout>
</ng-template>
</ListViewGridLayout>
</RadListView>
<RadListView [items]="transactions | async " >
<ng-template tkListItemTemplate let-item="item">
<GridLayout>
<Label [text]="item.transName"></Label>
</GridLayout>
</ng-template>
</RadListView>
deal-summary.component.ts
export class DealSummaryComponent implements OnInit {
public transactions: Observable<any>;
constructor(
private firebaseS: FirebaseService,
){ }
ngOnInit() {
this.transactions = <any>this.firebaseS.getMyTransactionList();
}
deal-summary.component.html
<RadListView [items]="transactions | async " >
<ng-template tkListItemTemplate let-item="item">
<GridLayout >
<Label col="1" [text]="item.transName"></Label>
</GridLayout>
</ng-template>
</RadListView>