onLoad: function (options) {

    let self = this

    target_id = options.target_id

    lesson_id = options.lesson_id

    lesson_title = options.lesson_title

    wx.setNavigationBarTitle({title: target_name,})

    this.set_lesson_title()

    this.chatService = new Chat();

    this.chatService = this.chatService.chat_api

    var upperCaseName = computed(() => {....});

    this.setData({ chatList: upperCaseName })

    upperCaseName.observe(change  => {

      self.setData({

        chatList: change.newValue

      })

      self.toBottom()

      self.setData({ load_over: true })

    })

    if (!(has_load_ids.indexOf(target_id) > -1)) {

      this.chatService.list_p2p_recent_msg(target_id)

      has_load_ids.push(target_id)

      wx.setStorageSync("has_load_ids", has_load_ids)

    }

}