HarmonyOS Component中如何监听嵌套类中基础类型的变化

LoginPage中有一个登录按钮，点击登录按钮时，会把LoginViewModel 中的loginStatus变量置为true，LoginPage中如何监听到loginStatus的变化？现在只能监听到整个LoginViewModel 的变化

LoginPage代码

import { LoginViewModel } from '../viewmodel/LoginViewModel';
import { hilog } from '@kit.PerformanceAnalysisKit';

@Entry
@Component
struct LoginPage {
  @State @Watch("onLoginVMChange") loginVM: LoginViewModel = new LoginViewModel()
  @State @Watch("onLoginStatusChange") loginStatus: boolean = this.loginVM.loginStatus

  build() {
    Button('登录')
      .width('200vp')
      .margin({ top: '20vp' })
      .onClick(() => {
        this.loginVM.login()
      })
  }

  onLoginStatusChange(changedPropertyName: string) {
    hilog.info(0x001, "TAG_LOGIN", "onLoginStatusChange")
  }

  onLoginVMChange(changedPropertyName: string) {
    hilog.info(0x001, "TAG_LOGIN", "onLoginVMChange")
  }
}

LoginViewModel代码

@Observed
export class LoginViewModel {
  userName: string = ''
  password: string = ''
  loginStatus: boolean = false

  login() {
    this.loginStatus = true
  }
}