HarmonyOS 输入框获取焦点后无法弹出

参考下述demo：

@Entry
@Component
struct DynamicControlKeyboard {
  private flag: boolean = false;
  @Builder
  Kb() {
    Row() {
      Text('自定义键盘')
    }
    .justifyContent(FlexAlign.Center)
    .width('1260px')
    .height('1161px')
    .backgroundColor(Color.Brown)
  }
  build() {
    Column({space: 10}) {
      TextInput()
        .key('key1')
        // .onAppear(() => {
        //   // focusControl.requestFocus('key1');
        // })
        .defaultFocus(false)
        .enableKeyboardOnFocus(true)
        // .focusOnTouch(this.focusFlag)
      TextInput()
        .key('key2')
        .customKeyboard(this.Kb())
      Button('切换TextInput')
        .onClick(() => {
          if (this.flag) {
            console.info('TextInput2 ==> ' + focusControl.requestFocus('key2'));
          }
          else {
            focusControl.requestFocus('key1')
          }
          this.flag = !this.flag;
        })
      Button()
        .width(0)
        .height(0)
        .key('key3')
    }
    .padding({ top: 20 })
    .width('100%')
    .height('100%')
    .onClick(() => {
      focusControl.requestFocus('key3');
    })
  }
}