通过valueAccessor.writeValue()设置值后，表单控件无效状态未更改

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

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

  ngOnInit() {
    this.myControl = new FormControl();

    // 设置表单控件的值
    this.myControl.setValue('example value');

    // 更新控件的状态
    this.myControl.updateValueAndValidity();
  }
}