onPullDownRefresh: function () {
    wx.showToast({
      title: \'loading...\',
      icon: \'loading\'
    })
    console.log(\'onPullDownRefresh\', new Date())
  },

 wx.stopPullDownRefresh({
      complete: function (res) {
        wx.hideToast()
        console.log(res, new Date())
      }
  })