lookup select box和select box 联动

var query = Class.create();
query.prototype = Object.extendsObject(global.AbstractAjaxProcessor, {

 querytable_info: function(){
  
  var result=this.newItem("result");
  var applyername = this.getParameter('sysparm_getName');
  
 var gr=new GlideRecord('x_178251_my_applic_bigproject');
  gr.addQuery('name',applyername);
  gr.query();
  while(gr.next()){
   
     result.setAttribute("q_mid",gr.mid);
   
  }
   var answer;
 
  var m_id = this.getParameter('sysparm_getId');
  var list="";
 var gm=new GlideRecord('x_178251_my_applic_mproject');
  gm.addQuery('id',m_id);
  gm.query();
  
  while(gm.next()){
   answer=this.newItem("ans");
   
    answer.setAttribute("q_name",gm.name);
   
  }
  
 

 },
    type: 'query'
});

function onChange(control, oldValue, newValue, isLoading) {
   if (isLoading || newValue == '') {
      return;
   }
    var sname=g_form.getValue("bigproject");
    var ga=new GlideAjax('query');
    ga.addParam('sysparm_name','querytable_info');
    ga.addParam('sysparm_getName',sname);

    ga.getXML(showDescription);
    function showDescription(serverResponse){
            var result=serverResponse.responseXML.getElementsByTagName("result");
        var b_mid=result[0].getAttribute("q_mid");
        //alert(b_mid);
        ga.addParam('sysparm_getId',b_mid);
        ga.getXML(callback);
        function callback(response){
            var m_name='';
            var answer=response.responseXML.getElementsByTagName("ans");
            g_form.clearOptions("mPro");
            for(var i=0;i<answer.length;i++){
            
                m_name=answer[i].getAttribute("q_name");
                g_form.addOption("mPro",m_name,m_name);
            }

            
        }
          
        
    }


   //Type appropriate comment here, and begin script below
   
}