select box 联动

//查询表格，取得去重复的name
var queryPro = Class.create();
queryPro.prototype = Object.extendsObject(global.AbstractAjaxProcessor, {
   queryPro_info:function(){
    var answer;
 var gr = new GlideAggregate('x_178251_my_applic_mypro');
         gr.groupBy('bname'); 
         gr.query();
    while(gr.next()){
   answer=this.newItem("ans");
          answer.setAttribute('q_bname',gr.bname);
}   
   },
    type: 'queryPro'
});

//将查询到的去重后的name塞到select box中
function onLoad() {
   //Type appropriate comment here, and begin script below
   var ga=new GlideAjax("queryPro");
    ga.addParam("sysparm_name","queryPro_info");
    ga.getXML(callback);
    var b_name='';
    function callback(response){
        var answer=response.responseXML.getElementsByTagName("ans");
        for(var i=0;i<answer.length;i++){
            b_name=answer[i].getAttribute('q_bname');
            g_form.addOption("bPro",b_name,b_name);
        }
    }
}

//根据选择的name值再次查询
function onChange(control, oldValue, newValue, isLoading) {
   if (isLoading || newValue == '') {
      return;
   }
 var bPro_value=g_form.getValue("bPro");
    var ga=new GlideAjax("addPro");
    ga.addParam("sysparm_name","addPro_info");
    ga.addParam("sysparm_getbname",bPro_value);
    ga.getXML(callback);
    function callback(response){
        var answer=response.responseXML.getElementsByTagName("res");
        g_form.clearOptions("mPro");
        for(var i=0;i<answer.length;i++){
            var mPro_value=answer[i].getAttribute('q_mname');
            //alert(answer[i].getAttribute('q_mname'));
            g_form.addOption("mPro",mPro_value,mPro_value);
        }
    }
   //Type appropriate comment here, and begin script below
   
}

//根据前台得到的select box的值，再次查询表格得到要联动的select box的值
var addPro = Class.create();
addPro.prototype = Object.extendsObject(global.AbstractAjaxProcessor, {
  addPro_info:function(){
     
      var b_name=this.getParameter("sysparm_getbname");
       var gr=new GlideRecord('x_178251_my_applic_mypro');
      gr.addQuery("bname",b_name);
      gr.query();
      while(gr.next()){
          var result=this.newItem("res");
          result.setAttribute('q_mname',gr.mname);
      }
      
      
  },
    
    
    type: 'addPro'
});