Ionic 2 Tab view not update tabBadge when model change but only update when click on the tab - ionic2

Question

I have this code that show the tabBadge number
<ion-tabs selectedIndex="{{activeTab}}">
<ion-tab [root]="tabThongBaoPage" tabIcon="notifications" [tabBadge]="badge.getBadge()" tabBadgeStyle="danger"></ion-tab>
</ion-tabs>
and the service controller the bag number
import { Injectable } from '#angular/core';
import { Http } from '#angular/http';
import 'rxjs/add/operator/toPromise';
import CONST from '../variable';
#Injectable()
export class BadgeSinhService {
badge: number = 0;
constructor() {
}
getBadge(): number {
return this.badge;
}
setBadge(badge): number {
this.badge = badge;
return this.badge;
}
incrementBadge() {
this.badge++
return
}
decreaseBadge() {
if (this.badge > 0) {
this.badge--
}
return;
}
}
If I click on the button with event like this
<button ion-button (click)="cong()">Cong</button>
<button ion-button (click)="tru()">Tru</button>
cong() {
this.badge.incrementBadge()
}
tru() {
this.badge.decreaseBadge()
}
The tabBadge number updated on the view, as soon as the button is click and the click event is fire
But I also have this code that wait for notification event, that will be fire when the server send a notification to the app, it will increment the tab badge number
push.on('notification', (data) => {
console.log('notifi updatei');
this.badge.incrementBadge();
})
It does increment the tab badge number but the view is not update, only when I tap on the tab then the badge number will update on the view
Why it not update the view like the click event ?

Answer 1

I found the answer,use ngZone to notifi angular2 to update the view
push.on('notification', (data) => {
console.log('notifi updatei');
this.badge.incrementBadge();
})
somehow the code above not create a async task in angular 2 zone, maybe because push.on not belong to angular 2
but the answer is
this.zone.run(() => {
// increment badge
})