HarmonyOS鸿蒙Next中@State修饰的变量，变化后UI不更新

HarmonyOS鸿蒙Next中@State修饰的变量，变化后UI不更新 父组件 HomeCategory，子组件 QuestionItemListComp

父组件中调用子组件，同时向子组件传参，子组件的aboutToApper方法中，会根据这个参数获取请求结果。我通过log日志打印，发现请求结果是能获取到的，但是为什么UI不更新

import { PageData, QuestionItem } from "../../models"
import { promptAction } from "@kit.ArkUI"
import { http } from "../utils/Http"
import { JSON } from "@kit.ArkTS"
import { logger } from "../utils/Logger"
import json from "@ohos.util.json"
import { QuestionItemListComp2 } from "./QuestionItemListComp2"

interface QuestionType {
  name: string,
  displayNewestFlag: 1|0,
  id: number
}

interface QuestionItemType{
  text:string,
  color:Resource
}

const diffColorText:Record<number,QuestionItemType>={
  1:{text:'简单',color:$r('app.color.common_green')},
  2:{text:'简单',color:$r('app.color.common_green')},
  3:{text:'一般',color:$r('app.color.common_blue')},
  4:{text:'一般',color:$r('app.color.common_blue')},
  5:{text:'困难',color:$r('app.color.common_main_color')}
}

interface QuestionItemListParam{
  type?:string,
  keyword?:string,
  sort?:string,
  pageSize?:string,
  page?:string,
  questionBankType:string
}

@Component
struct QuestionItemListComp {

  [@State](/user/State)
  questionItemList:QuestionItem[]=[]

  @Prop
  type:string ='401'


  async getQuestionItemList(type:string,page:string,sort:string='0',pageSize:string='10',questionBankType:string='10'){
    let result = await http.request<PageData<QuestionItem>>({
      url:'test/question/list',
      params:{
        type, //QuestionItem的id
        keyword:'', //保持为空
        sort,
        pageSize,
        page,
        questionBankType
      } as QuestionItemListParam
    })
    // this.questionItemList.push(...result.rows)
    return result
  }

  async aboutToAppear(){
    const result = await this.getQuestionItemList(this.type,'1')
    // this.questionItemList.push(...result.rows)
    this.questionItemList = result.rows
    logger.info(JSON.stringify(result.rows))
  }


  //问题条框Builder
  @Builder
  QuestionItemBuilder(questionItem:QuestionItem) {
    Column({space:10}){
      Row(){
        Text(diffColorText[questionItem.difficulty].text)
        Text(questionItem.stem)
      }
      RowSplit(){
        Text(`点赞 ${questionItem.likeCount}`)
          .padding({right:10})
        Text(`浏览 ${questionItem.views}`)
          .padding({left:10,right:10})
        if (questionItem.readFlag==1){
          Text('已看过')
            .padding({left:10,right:10})
        }
      }

    }
    .margin({top:15,bottom:15})
    .alignItems(HorizontalAlign.Start)
  }

  //存放问题条框的Builder
  @Builder
  QuestionItemListBuilder(questionItems:QuestionItem[]){
    Refresh({refreshing:false}){
      List(){
        ForEach(questionItems,(item:QuestionItem,index:number)=>{
          this.QuestionItemBuilder(item)
        })
      }
      // .backgroundColor(Color.Green)
      .divider({
        strokeWidth:1,
        color:'#ffc8c8c8'
      })
      .padding({left:10,right:10})
    }
    .height('100%')
    .width('100%')

  }

  build() {
    this.QuestionItemListBuilder(this.questionItemList)
  }
}


@Component
@Preview
export struct HomeCategory {
  [@State](/user/State)
  type:string = '0'
  [@State](/user/State)
  questionTypeList: QuestionType[] = []
  [@State](/user/State)
  activeIndex: number = 0
  [@State](/user/State)
  freshFlag:boolean = false
  [@State](/user/State)
  questionItemList:QuestionItem[]=[]


  async getQuestionTypeList(){
    let result = await http.request<QuestionType[]>({
      url:'hm/question/type'
    })
    this.questionTypeList = result
  }

  //顶部问题分类builder
  @Builder
  QuestionTypeBuilder(questionType: QuestionType,index:number) {
    Row() {
      Text(questionType.name) //问题类型
        .margin({right:4})
      if (questionType.displayNewestFlag==1) { //如果是true，就显示图片new
        Image($r('app.media.ic_home_new'))
          .width(40)
      }
    }
    .padding({ left: 5, right: 5 })
    // .border({
    //   width: { bottom: this.activeIndex==questionType.id?1:0 },
    //   color: $r('app.color.black')
    // })
    .backgroundColor(this.activeIndex==index? '#ffe5e5e5' :'#00000000')
    .borderRadius('50%')

  }


  aboutToAppear(): void {
    this.getQuestionTypeList()
  }

  build() {
    Tabs() {
      ForEach(this.questionTypeList, (item: QuestionType, index: number) => {
        TabContent() {
          QuestionItemListComp({type:item.id.toString()})
        }.tabBar(this.QuestionTypeBuilder(item,index))

      })
    }
    .barMode(BarMode.Scrollable)
    .backgroundColor(Color.White)
    .barPosition(BarPosition.Start)
    .barHeight(40)
    .divider({ strokeWidth: 1, color: $r('app.color.common_gray_01') })
    // .onChange((index)=>{
    //   this.activeIndex = index
    // })
    .onTabBarClick((index:number)=>{
      this.activeIndex = index


    })

    // .height(60)


  }


}