selectSingleNode , I got a problem

the figure shown as below.

I get a dialog, when I  click red frame(2)   , I use  var npd_appitem = parent.item.selectSingleNode("//Item[@type= ' NewProductPJ']");

var npdid = a.getItemProperty(npd_appitem,"id");    get item Id , but  got  orange frame(3) Item Id.

Please help.