HarmonyOS 如何触发更新自定义组件里的数据并让其刷新UI？

@Observed  
class MyViewModel {  
  title: string = ""  
  constructor(title:string) {  
    this.title = title  
  }  
}  
  
@Entry  
@Component  
export struct MyComponent {  
  
  @State vm: MyViewModel = new MyViewModel("1")  
  
  build() {  
    Row(){  
      OtherComponenft({vm:this.vm})  
        .onClick(()=>{  
          this.vm.title = "222"  
        })  
    }.width("100%")  
    .height(100)  
  }  
}  
  
@Component  
struct OtherComponenft {  
  @ObjectLink vm: MyViewModel  
  build() {  
    Text(this.vm.title)  
      .fontSize(20)  
      .fontColor(Color.Black)  
      .width(200)  
      .height(50)  
      .margin({  
        left:20  
      })  
  }  
}