Angular 2 @ViewChild annotation returns undefined

I am trying to learn Angular 2.

I would like to access to a child component from a parent component using the @ViewChild Annotation.

Here some lines of code:

In BodyContent.ts I have:

import { ViewChild, Component, Injectable } from 'angular2/core';
import { FilterTiles } from '../Components/FilterTiles/FilterTiles';

@Component({
    selector: 'ico-body-content',
    templateUrl: 'App/Pages/Filters/BodyContent/BodyContent.html',
    directives: [FilterTiles] 
})
export class BodyContent {
    @ViewChild(FilterTiles) ft: FilterTiles;

    public onClickSidebar(clickedElement: string) {
        console.log(this.ft);
        var startingFilter = {
            title: 'cognomi',
            values: [ 'griffin', 'simpson' ]
        }
        this.ft.tiles.push(startingFilter);
    } 
}

while in FilterTiles.ts:

import { Component } from 'angular2/core';

 @Component({
     selector: 'ico-filter-tiles',
     templateUrl: 'App/Pages/Filters/Components/FilterTiles/FilterTiles.html'
 })
 export class FilterTiles {
     public tiles = [];

     public constructor(){};
 }

Finally here the templates (as suggested in comments):

BodyContent.html






FilterTiles.html

Tiles loaded

... stuff ...



FilterTiles.html template is correctly loaded into ico-filter-tiles tag (indeed I am able to see the header).

Note: the BodyContent class is injected inside another template (Body) using DynamicComponetLoader: dcl.loadAsRoot(BodyContent, '#ico-bodyContent', injector):

```
import { ViewChild, Component, DynamicComponentLoader, Injector } from 'angular2/core';
import { Body } from '../../Layout/Dashboard/Body/Body';
import { BodyContent } from './BodyContent/BodyContent';

@Component({
selector: 'filters',
templateUrl: 'App/Pages/Filters/Filters.html',
directives: [Body, Sidebar, Navbar]
})
export class Filters {

constructor(dcl: DynamicComponentLoader, injector: Injector) {
dcl.loadAsRoot(BodyContent, '#ico-bodyContent'

I had a similar issue and thought I'd post in case someone else made the same mistake. First, one thing to consider is AfterViewInit; you need to wait for the view to be initialized before you can access your @ViewChild. However, my @ViewChild was still returning null. The problem was my ngIf. The ngIf directive was killing my controls component so I couldn't reference it.

import { Component, ViewChild, OnInit, AfterViewInit } from 'angular2/core';
import { ControlsComponent } from './controls/controls.component';
import { SlideshowComponent } from './slideshow/slideshow.component';

@Component({
  selector: 'app',
  template: `
    
    
  `,
  directives: [SlideshowComponent, ControlsComponent],
})
export class AppComponent {
  @ViewChild(ControlsComponent) controls: ControlsComponent;

  controlsOn: boolean = false;

  ngOnInit() {
    console.log('on init', this.controls);
    // this returns undefined
  }

  ngAfterViewInit() {
    console.log('on after view init', this.controls);
    // this returns null
  }

  onMouseMove(event) {
    this.controls.show();
    // throws an error because controls is null
  }
}

EDIT

As mentioned by @Ashg below, a solution is to use @ViewChildren instead of @ViewChild.

Stack Overflow Q#34947154, score: 558