var that=this;//把this对象复制到临时变量that

success: res =>{
  this.setData({
      loadingHidden: true,
      hideCommitSuccessToast: false
  })
}

  success: res => {
    if (res.data.code != 0) {
     // 提交失败
     this.setData({
      loadingHidden: true,
      hiddenTips: false,
      tipsContent: res.data.message
     })
    } else {
     // 提交成功
     this.setData({
      loadingHidden: true,
      hideCommitSuccessToast: false
     })
     subBtn = false;

     // 定时，3秒消失
     setTimeout(() => {
      this.setData({
       hideCommitSuccessToast: true
      })
      wx.navigateBack({ delta: 2 });
     }, 2000);

    }
   }