block24.ts

@Component({
  ...
  template:`
    {{count}}
    <button (click)="up()">Click</button>
  `,
  changeDetection: ChangeDetectionStrategy.OnPush
})
export class DOMComponent{
  count = 0
  constructor() {
    setTimeout(()=> this.count++,0)
  }
  up(){this.count++}
}