如何在valueChanges订阅回调中将焦点动态设置回元素？

import { Component, ViewChild, ElementRef } from '@angular/core';
import { FormControl } from '@angular/forms';

@Component({
  selector: 'app-example',
  template: `
    <input type="text" [formControl]="myControl">
  `
})
export class ExampleComponent {
  myControl = new FormControl();
}

@Component({
  selector: 'app-example',
  template: `
    <input #inputElement type="text" [formControl]="myControl">
  `
})
export class ExampleComponent {
  @ViewChild('inputElement') inputElement: ElementRef;
  myControl = new FormControl();
}

import { Component, ViewChild, ElementRef, OnInit } from '@angular/core';
import { FormControl } from '@angular/forms';

@Component({
  selector: 'app-example',
  template: `
    <input #inputElement type="text" [formControl]="myControl">
  `
})
export class ExampleComponent implements OnInit {
  @ViewChild('inputElement') inputElement: ElementRef;
  myControl = new FormControl();

  ngOnInit() {
    this.myControl.valueChanges.subscribe(() => {
      this.inputElement.nativeElement.focus();
    });
  }
}