JS: ERROR Error: Uncaught (in promise): Run init() first!

i run into this error once i lunch my app, i believe the error is caused by the firebase.service component inside the ngOnInit here is code sample `import { Component, OnInit, AfterViewInit, ViewChild, ElementRef } from "@angular/core";

import { Observable } from 'rxjs/Observable';

import { BackendService, FirebaseService } from "../services";

import { ListView } from 'ui/list-view';

import { TextField } from 'ui/text-field';

import { ScrollView } from 'ui/scroll-view';

@Component({

moduleId: module.id,

selector: "chat-tab",

templateUrl: "chat.tab.component.html",

styleUrls: ["chat.tab.component.css"]

})

export class ChatTabComponent implements OnInit {

public me: String;

@ViewChild("list") lv: ElementRef;

@ViewChild("textfield") tf: ElementRef;

list: ListView;

textfield: TextField;

public constructor(

    private firebaseService: FirebaseService

) { }

public chats$: Observable<any>;

public ngOnInit() {

    this.me = BackendService.token;

    **this.chats$ = <any>this.firebaseService.getChats();**       

}

public ngAfterViewInit() {

    this.list = this.lv.nativeElement;

    this.textfield = this.tf.nativeElement;

}

scroll(count:number){

   console.log("scrolling to ", count)

   this.list.scrollToIndex(count-1);

   this.list.refresh();

}

chat(message: string) {

    this.firebaseService.chat(message).then((data: any) => {

        let count = this.list.items.length;

        this.scroll(count);

    });

    this.textfield.text = '';        

}

filter(sender) {

    if (sender == BackendService.token) {

        return "me"

    }

    else {

        return "them"

    }

}

align(sender) {

    if (sender == BackendService.token) {

        return "right"

    }

    else {

        return "left"

    }
}

showImage(sender) {

    if (sender == BackendService.token) {

        return "collapsed"
    }

    else {

        return "visible"

    }

}

} ` and here is the firebaseservice

`import {Injectable, NgZone} from "@angular/core";

import {User, Yowl} from "../models";

import { BackendService } from "./backend.service";

import firebase = require("nativescript-plugin-firebase");

import {Observable} from 'rxjs/Observable';

import {BehaviorSubject} from 'rxjs/BehaviorSubject';

import 'rxjs/add/operator/share';

@Injectable()

export class FirebaseService {

constructor(

private ngZone: NgZone,

){}

yowls: BehaviorSubject<Array> = new BehaviorSubject([]);

private _allYowls: Array = [];

chats: BehaviorSubject<Array> = new BehaviorSubject([]);

private _allChats: Array = [];

getMessage(){

firebase.addOnMessageReceivedCallback(function (data ){

    alert(JSON.stringify(data));

})

}

return firebase.createUser({

  email: user.email,

  password: user.password

}).then(

      function (result:any) {

        return JSON.stringify(result);

      },

      function (errorMessage:any) {

        alert(errorMessage);

      }

  )

}

return firebase.login({

  type: firebase.LoginType.PASSWORD,

  passwordOptions: {

    email: user.email,

    password: user.password

  }

}).then((result: any) => {

      BackendService.token = result.uid;

      return JSON.stringify(result);

  }, (errorMessage: any) => {

    alert(errorMessage);

  });

}

logout(){

BackendService.token = "";

firebase.logout();

}

resetPassword(email) {

return firebase.resetPassword({

email: email

}).then((result: any) => {

      alert(JSON.stringify(result));

    },

    function (errorMessage:any) {

      alert(errorMessage);

    }

).catch(this.handleErrors);

}

getYowls(): Observable {

return new Observable((observer: any) => {

  let path = 'Yowls';

    let onValueEvent = (snapshot: any) => {

      this.ngZone.run(() => {

        let results = this.handleSnapshot(snapshot.value);

         observer.next(results);

      });

    };

    firebase.addValueEventListener(onValueEvent, `/${path}`);

}).share();

}

handleSnapshot(data: any) {

//empty array, then refill and filter

this._allYowls = [];

if (data) {

  for (let id in data) {        

    let result = (<any>Object).assign({id: id}, data[id]);

      this._allYowls.push(result);

  }

  this.publishUpdates();

}

return this._allYowls;

}

getChats(): Observable {

return new Observable((observer: any) => {

  let path = 'Chats';

    let onValueEvent = (snapshot: any) => {

      this.ngZone.run(() => {

        let results = this.handleChatSnapshot(snapshot.value);

         observer.next(results);

      });

    };

    firebase.addValueEventListener(onValueEvent, `/${path}`);

}).share();

}

handleChatSnapshot(data: any) {

//empty array, then refill and filter

this._allChats = [];

if (data) {

  for (let id in data) {        

    let result = (<any>Object).assign({id: id}, data[id]);

      this._allChats.push(result);

  }

  this.publishChatUpdates();

}

return this._allChats;

}

sendYowl(Yowl:any) {

let yowl = Yowl;   

return firebase.push(

    "/Yowls",

    { "name": "Mr. Growlllr", "username": "MrGrwwlr", "text": "Yooowwwwlll!", "UID": BackendService.token, "date": 0 - Date.now()}

  ).then(

    function (result:any) {

      return 'Yowwled!';

    },

    function (errorMessage:any) {

      console.log(errorMessage);

    });

}

chat(message:string) {

//let chat = Chat; 

console.log(message)  

return firebase.push(

    "/Chats",

    { "message": message, "to": "MrGrwwlr", "from": BackendService.token, "date": 0 - Date.now()}

  ).then(

    function (result:any) {

      return "chatted";

    },

    function (errorMessage:any) {

      console.log(errorMessage);

    });

}

publishUpdates() {

this._allYowls.sort(function(a, b){

    if(a.date < b.date) return -1;

    if(a.date > b.date) return 1;

  return 0;

})

this.yowls.next([...this._allYowls]);

}

publishChatUpdates() {

this._allChats.sort(function(a, b){

    if(a.date > b.date) return -1;

    if(a.date < b.date) return 1;

  return 0;

})

this.chats.next([...this._allChats]);

}

handleErrors(error) {

console.log(JSON.stringify(error));

return Promise.reject(error.message);

}

} ` i already init firebase in app.component.ts

`import { Component, OnInit } from "@angular/core";

const firebase = require("nativescript-plugin-firebase");

const dialogs = require("ui/dialogs");

import { BackendService } from "./services/backend.service";

@Component({

selector: "yw-main",

template: ""

})

export class AppComponent implements OnInit {

ngOnInit(): void {

firebase.init({

  /*onPushTokenReceivedCallback: function(token) {

    alert("Firebase push token: " + token);

  },*/

  onMessageReceivedCallback: function(message) {

    dialogs.alert({

      title: "Push message: " + (message.title !== undefined ? message.title : ""),

      message: JSON.stringify(message.body),

      okButtonText: "W00t!"

    });

  },

  //persist should be set to false as otherwise numbers aren't returned during livesync

  persist: false,

  //storageBucket: 'gs://yowwlr.appspot.com',

  onAuthStateChanged: (data: any) => {

    if (data.loggedIn) {

      BackendService.token = data.user.uid;

    }

    else {

      BackendService.token = "";

    }

  }

}).then(

    function (instance) {

      console.log("firebase.init done");

    },

    function (error) {

      console.log("firebase.init error: " + error);

    }

);

}

} `

EddyVerbruggen / nativescript-plugin-firebase

JS: ERROR Error: Uncaught (in promise): Run init() first! #890