JEASYUI : membuat event handler closable dialog jeasyui

     <div id="dlgad" class="easyui-dialog" style="width:380px;height:auto;padding:10px 20px"
            closed="true" buttons="#dlgad-buttons" data-options="iconCls:'icon-save',resizable:true,collapsible:true,maximizable:true,closable:false,tools:[{ 
            iconCls:'icon-cancel', 
            handler:function(){ 
                if(confirm('Are you sure to close the window?'))
                    {
                        javascript:$('#dlgad').dialog('close');
                    }
                    else
                    {

                    }

            } 
        }]  ">