App({
  globalData: {
    nonetwork: false   //判斷是否有網絡
  },
  onShow() {
    this.onNetworkStatusChange()  //開啟檢測
  },
  onNetworkStatusChange() {
    var that = this
    //獲取網絡類型
    wx.getNetworkType({
      success: function (res) {
        const networkType = res.networkType
        //不為none代表有網絡
        if ('none' != networkType) {
          that.globalData.nonetwork = true
          //網絡狀態變化事件的回調函數   開啟網絡監聽，監聽小程序的網絡變化
          wx.onNetworkStatusChange(function (res) {
            if (res.isConnected) {
              //網絡變為有網
              that.globalData.nonetwork = true
            } else {
              //網絡變為無網
              that.globalData.nonetwork = false
            }
          })
        } else {
           //無網狀態
          wx.onNetworkStatusChange(function (res) {
            if (res.isConnected) {
              that.globalData.nonetwork = true
            } else {
              that.globalData.nonetwork = false
            }
          })
        }
      },
    })
  }

})

const app = getApp()
Page({
  data: {
    nonetwork: false
  },
  onLoad() {
     //判斷是否網絡
    if (app.globalData.nonetwork) {
      this.setData({
        nonetwork: true
      })
      //添加轉圈
      wx.showLoading({
        title: "獲取數據中!"
      });
    } else {
      this.setData({
        nonetwork: false
      })
      wx.showToast({
        title: '請連接網絡',
        icon: 'none',
        duration: 2000
      })
    }
  },
  doRefresh() {
    //無網絡的刷新
    this.onLoad()
  }
})

<view wx:if="{{nonetwork}}">
  內容
</view>
<view wx:else>
  <button bindtap="doRefresh">刷新</button>
</view>