代码如下:

var that = this;

var markerList = [];

db.collection('lost_found').get().then(res => {

var lists = res.data.reverse();

markerList=lists;

for (var i = 0; i < markerList.length; i++) {

that.setData({

'markersObj.id': this.data.markers.length + 1,

'markersObj.longitude': markerList[i].longitude,

'markersObj.latitude': markerList[i].latitude,

})

switch (markerList[i].signName) {

case 'foundThings': that.setData({

'markersObj.iconPath': "../../images/8.png",

'markersObj.callout.content': "失物招领",

'markersObj.callout.color': "#FF3333"

});break;

case 'clubActivity': that.setData({

'markersObj.iconPath': "../../images/10.png",

'markersObj.callout.content': "社团活动",

'markersObj.callout.color': "#FF5511"

});break;

case 'market': that.setData({

'markersObj.iconPath': "../../images/9.png",

'markersObj.callout.content': "二手市场",

'markersObj.callout.color': "#33CCFF"

});break;

}

app.globalData.markerArray.push(this.data.markersObj);

}

}).catch(err => { console.error(err) })

我在onShow里用console.log("长度"+app.app.globalData.markerArray.length)

控制台显示长度为0，我想问一下为什么用setData出回调函数后全局数据就未被修改呢？求好心人给我讲解或者修改一下代码谢谢了！！！！