HarmonyOS 鸿蒙Next 帮我看看这代码有什么问题，为什么点按钮没有反应

HarmonyOS 鸿蒙Next 帮我看看这代码有什么问题，为什么点按钮没有反应

班级成员

点名逻辑

interface Student {
  id: number
  name: string
  url: string
  count: number
}

@Entry
@Component
struct Index{
  @State flag: number = 1
  @State randomIndex: number = -1 //表示还没开始点名
  @State name: string = "" //名字
  @State studentArray: Student[]=[
    {id: 1, name: "张三", url: 'app.media.picture0', count: 0},
    {id: 2, name: "李四", url: 'app.media.picture1', count: 0},
    {id: 3, name: "王五", url: 'app.media.picture2', count: 0},
    {id: 4, name: "王五", url: 'app.media.picture3', count: 0},
    {id: 5, name: "王五", url: 'app.media.picture4', count: 0}
  ]
  //遮罩参数
  @State maskOpacity: number = 0 //透明度
  @State maskZIndex: number = -1 //显示层级
  //控制图片缩放
  @State maskImgX: number = 0 //水平缩放比
  @State maskImgY: number = 0 //垂直缩放比
  build() {
    Column(){
    Stack() {
      Column() {
        Text("班级成员")
          .fontSize(40)
          .width(200)
          .margin({ top: 20 })
        Grid() {
          ForEach(this.studentArray, (item: Student, index: number) => {
            GridItem() {
              Badge({
                count: item.count,
                position: BadgePosition.RightTop,
                style: {
                  fontSize: 14,
                  badgeSize: 20,
                  badgeColor: '#fa2a2d'
                }
              }) {
                Image($r(item.url))
                  .width(100)
                  .height(100)
              }
            }
          })

        }
        .columnsTemplate('1fr 1fr 1fr')
        .rowsTemplate('1fr 1fr')
        .width('100%')
        .height(300)
        .margin({ top: 20 })
      }

      Button('开始点名')
        .width(200)
        .backgroundColor('#ed5b8c')
        .margin({ top: 50 })
        .onClick(() => {
          //点击时，修改遮罩参数，让遮罩显示
          this.maskOpacity = 1
          this.maskZIndex = 99
          //点击时，图片需要缩放
          this.maskImgX = 1
          this.maskImgY = 1
          //生成随机数Math.random()
          this.flag = 2;
          this.randomIndex = Math.floor(Math.random() * 6)
          if (this.studentArray[this.randomIndex].count) {
            for (let item of this.studentArray) {
              if (item.count) {
                this.flag = 2
                this.randomIndex = item.id - 1
                break
              } else
                this.flag = 1
            }
          }
          if (this.flag == 2)
            this.name = this.studentArray[this.randomIndex].name
          else this.name = "班级成员全部点完名字"
        })
      //抽卡遮罩层
      Column({ space: 30 }) {
        Text('幸运星')
          .fontColor('#f5ebcf')
          .fontSize(25)
          .fontWeight(FontWeight.Bold)
        Text(this.name)
          .fontColor('#f5ebcf')
          .fontSize(25)
          .fontWeight(FontWeight.Bold)

        Image($r(`app.media.picture${this.randomIndex}`))
          .width(200) //控制元素缩放
          .scale({
            x: this.maskImgX,
            y: this.maskImgY
          })
          .animation({ duration: 500 })
        Button('重新点名')
          .width(200)
          .height(50)
          .backgroundColor(Color.Transparent)
          .border({ width: 2, color: '#fff9e0' })
          .onClick(() => {
            //控制弹窗显影
            this.maskOpacity=0
            this.maskZIndex=-1
            //图像重置缩放比为0
            this.maskImgX=0
            this.maskImgY=0
            //对象数组情况需要更新，需要修改替换整个对象
            this.studentArray[this.randomIndex]={
              id:this.studentArray[this.randomIndex].id,
              name:this.studentArray[this.randomIndex].name,
              url:`app.media.picture${this.randomIndex}`,
              count:this.studentArray[this.randomIndex].count+1
            }
          })

      }
      .justifyContent(FlexAlign.Center)
      .width('100%')
      .height('100%')
      .backgroundColor('#cc000000')
      //设置透明度
      .opacity(this.maskOpacity)
      .zIndex(this.maskZIndex)
      //动画
      .animation({duration:200})
    }}