React example compared to Angular 2 - https://facebook.github.io/react/tips/expose-component-functions.html

angular-todos.ts

import { Component, Input, ViewChildren } from '@angular/core';
import 'rxjs/add/operator/filter';

@Component({
    selector: 'todo',
    template: `
        <div>{{title}}</div>
    `
})
class Todo {
    @Input() title;

    animate() {
        console.log(`Pretend ${this.title} is animating`);
    }
}

@Component({
    template: `
        <div *ngFor="let item of items; let i = index">
            <todo (click)="handleClick(i)" [title]="item"></todo>
        </div>
    `,
    directives: [Todo]
})
export class Todos {
    items = ['Apple', 'Banana', 'Cranberry'];
    @ViewChildren(Todo) todoRefs;

    ngAfterViewInit() {
        this.todoRefs.changes
            .filter( todoRefs => todoRefs.length === 1 )
            .subscribe( todoRefs => todoRefs.last.animate() );
    }

    handleClick(index) {
        this.items.splice(index, 1);
    }
}

react-todos.jsx

var Todo = React.createClass({
  render: function() {
    return <div onClick={this.props.onClick}>{this.props.title}</div>;
  },

  //this component will be accessed by the parent through the `ref` attribute
  animate: function() {
    console.log('Pretend %s is animating', this.props.title);
  }
});

var Todos = React.createClass({
  getInitialState: function() {
    return {items: ['Apple', 'Banana', 'Cranberry']};
  },

  handleClick: function(index) {
    var items = this.state.items.filter(function(item, i) {
      return index !== i;
    });
    this.setState({items: items}, function() {
      if (items.length === 1) {
        this.refs.item0.animate();
      }
    }.bind(this));
  },

  render: function() {
    return (
      <div>
        {this.state.items.map(function(item, i) {
          var boundClick = this.handleClick.bind(this, i);
          return (
            <Todo onClick={boundClick} key={i} title={item} ref={'item' + i} />
          );
        }, this)}
      </div>
    );
  }
});