HBuilder开发app ajax跨域 解决XMLHttpRequest

<div id="a1" onclick="testXHR()" style="font-size: 5em;">sss1</div>

  < script type = "text/javascript" >
        var url = 'http://192.168.0.122/lxty/index.php/index/index/testajax';
          var data;
          var xhr=null;
          function testXHR(){
              if(xhr){
                  return;
              }
              xhr=new plus.net.XMLHttpRequest();
              xhr.onreadystatechange=xhrStatechange;
              xhr.open( "GET", url);
              xhr.send();
          }
          function xhrStatechange(){
              if (xhr.readyState==4&&xhr.status == 200) {


                      data = JSON.parse(xhr.responseText);

                      //alert(data.a1)
                      for(i in data){alert(data[i])}


              }
          }

</ script >