java - How to prevent GXT Dialog from closing on failed validation -

i have simple gxt dialog window 2 buttons, "ok" , "cancel". when ok button pressed validate fields not empty , want prevent dialog window been closed haven't been able figure out how. here's have

super.getbuttonbyid(dialog.ok).addselectionlistener(new selectionlistener<buttonevent>() {         @override         public void componentselected(buttonevent ce) {             if(netscanname.getvalue() == null) {                 util.alert("all fields required!");                 return;             }         }     }); 

the event fires because window alert dialog continues close way. suggestions?

are using gxt 3.0.x?

using gxt 3.0.x solve request setting

dialog.sethideonbuttonclick(false); 

to manage closing of dialogbox use code:

dialog.getbuttonbyid(predefinedbutton.ok.name()).addselecthandler(new selecthandler() {   @override   public void onselect(selectevent event) {     if (netscanname.getvalue() == null) {       util.alert("all fields required!");     } else {       dialog.hide();     }   } }); 

don't know if code work earlier versons of gxt.