<button (click)="setText('new name')"></button>

<mybutton (click)="setText('new name')"></button>

click.emit(null);

<mybutton (click)="setText('new name')"></button>

@Component({
  (...)
  template: `
    <mybutton #comp (click)="comp.label = 'new name'"></button>
  `,
  directives: [ MyButton ]
})
(...)

@Component({
  selector: 'mybutton',
  template: `<button>{{label}}</button>`
})
export class MyButton {
  @Input() label: string;

  constructor() {
    this.label = 'test';
  }

  setText(newName: string) {
    this.label = newName;
  }
}

template: `<button (click)="setText()">{{label}}</button>`