看文档markers应该是个数组，我手动添加数组是能正常显示的，但是通过访问接口的success回调时push到数组新的内容时，地图上的所有标记都不显示了，这是什么情况啊，以下是代码：

var markers = [{
  id: '0',
  latitude: 36.18359383595297,
  longitude: 120.37397938541415,
  iconPath: '/assets/images/wxapp-scale-code-img@2x.png',
  width: 140,
  height: 36,
  title: "培训学校1"
}, {
  id: '1',
  latitude: 36.188841352893085,
  longitude: 120.37724095157625,
  iconPath: '/assets/images/wxapp-scale-code-img@2x.png',
  width: 140,
  height: 36,
  title: "培训学校2"
}]
Page({
  data: {
    scale: 14,
    markers: markers
  }
}),
onLoad: function() {
    var _this = this;
    wx.getLocation({
      type: 'gcj02', // 默认为 wgs84 返回 gps 坐标，gcj02 返回可用于 wx.openLocation 的坐标
      success: function(res) {
        console.log(res)
        _this.setData({
          latitude: res.latitude,
          longitude: res.longitude,
          markers: markers.push({
            id: "2",
            latitude: 36.187611768251,
            longitude: 120.38160222343447,
            width: 30,
            height: 30,
            iconPath: "/assets/images/walk@2x.png",
            title: "当前位置"
          }),
        });
    }
  })
 },