Ionic 2: How to call parent page function from Popover component

Question

I have a page component with a button that opens a PopoverController. According to the Ionic Docs, popovers need another specific component for its content.

In the main page I have a function that I need to call from the popover component, but I haven't found how to access to the "parents'" methods. I've tried with @ViewChild but the child is undefined.

import { Component, ViewChild } from '@angular/core';
import { Content, NavController, NavParams, Platform, PopoverController, ViewController } from 'ionic-angular';

// Parent page:
@Component({
    selector: 'page-favorites',
    templateUrl: 'favorites.html'
})
export class FavoritesPage {
    constructor(public popoverCtrl: PopoverController) {
    }

    openOptions(ev?: Event) {
        let popover = this.popoverCtrl.create(FavoritesPopover);
        popover.present({ ev: ev });
    }

    showConfirm() {
        // This is the function I need to call from FavoritesPopover
    }
}

// Popover content:
@Component({
  template: `
    <ion-list>
        <button ion-item (click)="showConfirm()">Show confirm</button>
    </ion-list>`
})
export class FavoritesPopover {
    @ViewChild(FavoritesPage) favoritesPage: FavoritesPage;

    showConfirm() {
        this.favoritesPage.showConfirm(); // It doesn't work, favoritesPage is undefined
    }
}

As you can see, I'm just starting to work with Ionic 2 and Angular, so any help would be so thankful!

Answer 1

You can pass data (and functions) to the popover by passing an object as the second argument to the create method:

openOptions(ev?: Event) {
    let popover = this.popoverCtrl.create(FavoritesPopover, {
        showConfirm: function() {
            alert('yay');
        }
    });
    popover.present({ ev: ev });
}

Then, you should inject NavParams to your popover view, and get the function you passed:

import {NavParams} from 'ionic-angular';

export class FavoritesPopover {
    constructor(public params: NavParams) {}

    showConfirm() {
        this.params.get('showConfirm')(); 
    }
}