"tabBar": {
    "position": "top", // 将此处bottom  改为 top 之后  tabbar就到顶部去了，但是图标没有了
    "list": [{
      "pagePath": "pages/realtime/realtime",
      "text": "实时监控",
      "iconPath": "/images/tabs/monitor.png",
      "selectedIconPath": "/images/tabs/monitor-active.png"
    }, {
      "pagePath": "pages/histrack/histrack",
      "text": "历史轨迹",
      "iconPath": "/images/tabs/track.png",
      "selectedIconPath": "/images/tabs/track-active.png"
    }, {
      "pagePath": "pages/device/device",
      "text": "设备管理",
      "iconPath": "/images/tabs/my.png",
      "selectedIconPath": "/images/tabs/my-active.png"
    }]
  },