HarmonyOS TabContent内组件只能垂直居中，期望能垂直置顶

import router from '@ohos.router';  
  
@Entry  
@Component  
struct Index {  
  @State message: string = 'Hello World'  
  
  
  build() {  
    // Row是个垂直置顶组件，但打开TabContent注释后只能垂直居中  
    Tabs() {  
      TabContent() {  
  
        Column() {  
          Row() {  
            Text(this.message)  
              .width('100%')  
              .height('auto')  
              .textAlign(TextAlign.Center)  
              .onClick(() => {  
                this.message = 'clicked'  
  
                router.pushUrl({  
                  url: 'pages/MainComponent',  
                  params: {  
                    src: 'Index页面传来的数据',  
                  }  
                })  
              })  
          }  
          .width('100%')  
          .height('20%')  
          .alignItems(VerticalAlign.Top)  
          .backgroundColor('#33330000')  
  
        }  
        .height('100%')  
        .backgroundColor('#33330000')  
      }  
    }  
    .height('100%')  
  }  
}