cocos2d-js跨域访问问题，cocos2d-js请求网络数据

var HttpRequest = {
    /*
     * 网络请求之GET
     * url 请求的网络地址
     * callback 回调参数
     * */
    GET:function(url,callback){
        var xhr = cc.loader.getXMLHttpRequest();
        xhr.open("GET",url,true);
        xhr.onreadystatechange = function () {
            if (xhr.readyState == 4 && (xhr.status >= 200 && xhr.status <= 207)) {
                err = false;
            }else{
                err = true;
            }
            var response = xhr.responseText;
            callback(err,response);
        };
        xhr.send();
    },
    /*
     * 网络请求之POST
     * url 请求的网络地址
     * params  请求参数  ("id=1&id=2&id=3")
     * callback 回调参数
     * */
    POST:function(url,params,callback){
        var nums = arguments.length
        if(nums == 2){
            callback = arguments[1];
            params = "";
        }
        var xhr = cc.loader.getXMLHttpRequest();
        xhr.open("POST", url);
        xhr.setRequestHeader("Content-Type","text/plain;charset=UTF-8");
        xhr.onreadystatechange = function () {
            if (xhr.readyState == 4 && (xhr.status >= 200 && xhr.status <= 207)) {
                err = false;
            }else{
                err = true;
            }
            var response = xhr.responseText;
            callback(err,response);
        };
        xhr.send(params);
    }
}

//EXMAPLE
/*
 HttpRequest.POST("http://127.0.0.1:3000/test","id=1&ids=2", function(err,data){
 if(err){
 //错误处理
 }else{
 cc.log(data);
 }
 })
 */

<?php 
header("Access-Control-Allow-Origin : *");
echo "I Love you"
?>