Error when calling method in Provider

I have the following component


import { Component, Inject } from ‘@angular/core’;
import { NavController, Tabs } from ‘ionic-angular’;
import { AuthService } from ‘…/…/services/auth/auth.service’;
import { ReportService } from ‘…/…/services/reports/report.service’;
import { EnvVariables } from ‘…/…/app/environment-variables/environment-variables.token’;

selector: ‘page-newsfeed’,
templateUrl: ‘newsfeed.html’

export class Newsfeed {
report_list: {};
apiUrl: any;

static get parameters()
return [[Tabs]];

public tab: Tabs,
public navCtrl: NavController,
public authService: AuthService,
public reportService: ReportService,
@Inject(EnvVariables) public envVariables) { = tab;


ionViewDidLoad() {
openReportTab() {;

reportList() {
this.reportService.get_report_list().subscribe((results) => {
this.report_list = results;



and the following service


import { AuthHttp } from ‘angular2-jwt’;
import { Inject, Injectable } from ‘@angular/core’;
import { Storage } from ‘@ionic/storage’;
import { Http, Headers, Response, RequestOptions } from ‘@angular/http’;
import { Observable } from “rxjs/Observable”;
import { EnvVariables } from ‘…/…/app/environment-variables/environment-variables.token’;
import { GlobalErrorHandler } from ‘…/providers/error-handler’;
import { ToastHandler } from ‘…/providers/toasts’;


export class ReportService {

constructor(public authHttp: AuthHttp, private http: Http, @Inject(EnvVariables) public envVariables){

    var headers = new Headers();
  headers.append("Accept", 'application/json');
  headers.append('Content-Type', 'application/json');
  var options = new RequestOptions({headers: headers});


public get_report_list(): Observable {
console.log(“get report list”)
var url = “/api/v1/newsfeed”;
return this.authHttp.get(this.envVariables.apiEndpoint + url)
.map(res => res.json().data)


In my code, I am calling the get_report_list method in the constructor of the newsfeed component but I keep getting this error which is completely absurd

Unhandled Promise rejection: Cannot read property ‘get_report_list’ of undefined ; Zone:
angular ; Task: Promise.then ; Value: [object Object] TypeError: Cannot read property ‘get_report_list’ of
undefined at Newsfeed.webpackJsonp.304.Newsfeed.reportList (http://localhost:8100/build/main.js:387:28) at
Newsfeed.webpackJsonp.304.Newsfeed.ionViewDidLoad (http://localhost:8100/build/main.js:362:14) at
ViewController._lifecycle (http://localhost:8100/build/vendor.js:18359:33) at ViewController._didLoad
(http://localhost:8100/build/vendor.js:18232:14) at Tab.NavControllerBase._didLoad
(http://localhost:8100/build/vendor.js:47611:18) at t.invoke
(http://localhost:8100/build/polyfills.js:3:8488) at Object.onInvoke
(http://localhost:8100/build/vendor.js:4796:37) at t.invoke
(http://localhost:8100/build/polyfills.js:3:8428) at (http://localhost:8100/build/polyfills.js:3:3686)
at (http://localhost:8100/build/vendor.js:4665:62)

Completely confused and i dont know why this error exists. Can someone point me in the right direction?


If you think that’s what is causing the problem, why didn’t you post that line?

Also, you don’t need @Inject. I doubt that’s causing your problem, but it is more clutter than you need. Just public variable: Type.

How old is this code?

Wasn’t static get parameters() Ionic 2 beta syntax?

Yes. Now deprecated, though I’ve never tested to see what happens if you still use it.

I did post it. im calling it via the reportList() in newsfeed component

Your constructor is basically empty. Your English does not refer to the version of code you posted. That’s a danger sign for anyone trying to help debug on a forum, just FYI. So you might want to decide what you want to communicate here.

oops sorry. it was in my ionViewLoad() but anywys i removed the static get parameters method and it seems to be working so thanks @AaronSterling @SigmundFroyd for at least pointing me in the right direction.

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