Ionic 4/ Angular 6 - getting data outside lifecycle hook inside app.component

I have my navigation set up in my app.component.html , and I would like to use an *ngIf inside that template. However, since lifecycle hooks like ionViewWillEnter , etc don’t work in app.component.ts , how can I trigger a call to fire every time the side nav is popped open?

I am just trying to get a red dot to show if there are notifications in my array


      <ion-menu-toggle auto-hide="false" *ngFor="let p of appPages">
        <ion-item [routerDirection]="'root'" [routerLink]="[p.url]">
          <ion-icon slot="start" [name]="p.icon"></ion-icon>
          =====>HERE===><div class="red-dot" *ngIf="p.title == 'Home' && notifications.length > 0"></div> 
<ion-router-outlet main></ion-router-outlet>



initializeApp() {
const parseQueryString = (queryString) => {
  const query = <any>{};
  for (let param of queryString.split('&')) {
    const pair = param.split('=');
    query[pair[0]] = pair[1];
  return query;

this.platform.ready().then(() => {

What I want to add to the side nav logic

const newData = await this.api.listModel('Notification', {
this.notifications = this.notifications.concat(newData);
this.notifications = _.filter(this.notifications, { isActioned: false }