ubah di home.html:
line 12 <ion-item text-wrap *ngFor="let headline of headlines" (click)="openNavDetailsPage(headline)">

line 23 <ion-item text-wrap *ngFor="let headline1 of headliness " (click)="openNavDetailsPage(headline1) ">

ubah dihome.ts:
  openNavDetailsPage(headline) {
    this.navCtrl.push(DetailPage,{itemHeadline: headline})
  }

ubah di detail.ts:
import { Component } from '@angular/core';
import { IonicPage, NavController, NavParams } from 'ionic-angular';
import { RestProvider } from '../../providers/rest/rest';
import { Post_id} from '../../providers/providers';
import { Api } from '../../providers/api/api';

/**;;
 * Generated class for the DetailPage page.
 *
 * See https://ionicframework.com/docs/components/#navigation for more info on
 * Ionic pages and navigation.
 */

@IonicPage()
@Component({
  selector: 'page-detail',
  templateUrl: 'detail.html',
})
export class DetailPage {
  defaultItems: any;
  users: any;
  item: any;

  constructor(public navCtrl: NavController, public navParams: NavParams, public restProvider: RestProvider, public post_id: Post_id,public post_title: Post_title, public api: Api) {

    this.item = navParams.get('itemHeadline');
    console.log(this.item);


  }
}


ubah di detail.html

<ion-header>

    <ion-navbar>
        <ion-title>{{ item.post_id }}</ion-title>
    </ion-navbar>

</ion-header>


<ion-content>

    <div class="bold">

        {{ item.post_title }}

    </div>


</ion-content>