HarmonyOS 如何去掉bindMenu传入视图背景的圆角效果，使之宽度铺满屏幕

UI的下拉框效果是没有圆角的，自定义的下拉menu是存在圆角效果的怎么去除，且使之宽度铺满屏幕具体代码如下：

Button('TEST')
  .width(100)
  .height(100)
  .margin({ right: 36 })
  .bindMenu(this.MenuBuilder)

@Builder MenuBuilder() {
  Flex({ direction: FlexDirection.Column, justifyContent: FlexAlign.Center, alignItems: ItemAlign.Center }) {
    ForEach(this.userDbList, (userEntity: UserEntity, index) => {
      Column() {
        Row() {
          Text(StringUtil.formatPhoneNum(userEntity.mobileNo)).fontSize($r('app.float.fp_16_size')).width("70%")
          Image($r("app.media.close_circle")).width(20).height(20).margin({ left: 45 })
            .onClick(() => {
              this.userDbList.splice(index, 1)
              AccountTableUtil.deleteAccountByCustomerNo(userEntity.customerNo)
            })
        }.justifyContent(FlexAlign.SpaceBetween)
        .width('100%')
        .height(30)
        .justifyContent(FlexAlign.Start)
        .align(Alignment.Center)
        .onClick(() => {
          this.account = userEntity.mobileNo
        })
        if (index != this.userDbList.length - 1) {
          Divider().height(10).width('80%').color('#ccc')
        }
      }.padding(5).height(40)
    })
  }.width('100%')
}