Component({
  data: {
    lastY: '',
    translateHeight: 0,
    state: -1,
    scrollTop: 0,
    enablePulldownFresh: false,
    platform: ''
  },
  options: {
    multipleSlots: true
  },
  properties: {
    upperDistance: {
      type: Number,
      value: 80
    }
  },
  ready() {
    this.getSystemInfo()
  },
  methods: {
    /*解决ios下拉页面可以触发，安卓只有上划页面才可以触发 */
    onPageScroll(e) {
      console.log('eonPageScroll', e)
      this.data.scrollTop = e.scrollTop
      this.data.enablePulldownFresh = false
    },
    touchstart(e) {
      console.log('下拉开始', e)
      console.log('this.data.scrollTop', this.data.scrollTop)
      this.data.lastY = e.touches[0].clientY
      if (this.data.scrollTop === 0) {
        this.data.enablePulldownFresh = true
      } else {
        this.data.enablePulldownFresh = false
      }
    },
    touchmove(e) {
      console.log('下拉中', e)
      let clientY = e.touches[0].clientY
      let offset = clientY - this.data.lastY
      if (this.data.scrollTop > 0 || offset < 0) {
        return false
      }
      // this.data.translateHeight = offset
      /*解决ios下拉页面遮挡问题 */
      this.setData({
        //  translateHeight:this.data.lastY
        translateHeight: 100
      })
      this.data.state = 1
      if (this.data.enablePulldownFresh) {
        if (this.data.translateHeight > this.data.upperDistance) {
          this.data.state = 2
        }
        this.setData({
          translateHeight: this.data.translateHeight > 100 ? 100 : this.data.translateHeight,
          state: this.data.state
        })
      }
    },
    touchend(e) {
      if (this.data.translateHeight > this.data.upperDistance) {
        // 解决ios下来刷新数据不更新的问题
        if (this.data.platform == 'android') {
          if (this.data.enablePulldownFresh) {
            this.setData({
              translateHeight: 100,
              state: 3
            })
            this.triggerEvent('pullDownRefresh')
            return
          }
          this.stopRefresh()
        } else {
          if (!this.data.enablePulldownFresh) {
            this.setData({
              translateHeight: 100,
              state: 3
            })
            this.triggerEvent('pullDownRefresh')
            return
          }
          this.stopRefresh()
        }

      } else if (this.data.scrollTop <= 0) {
        console.log('停止下来刷新')
        this.stopRefresh()
      }
    },
    stopRefresh() {
      console.log('下拉刷新结束')
      this.setData({
        translateHeight: 0,
        state: -1
      })
    },
    getSystemInfo() {
      const res = wx.getSystemInfoSync()
      console.log('获取手机型号', res)
      this.setData({
        platform: res.platform//android,ios
      })
    }
  }
})