List<Warehouse> replacements=manager.findAll();
for (Warehouse replacement : replacements) {
Comboitem item=new Comboitem(replacement.getName());
warehousesCombo.appendChild(item);
}
Button okButton=new Button("OK");
okButton.addEventListener("onClick", new EventListener(){
public void onEvent(Event event) throws Exception {
if(nameBox.getText().equals("")){
Messagebox.show("Name is empty!", "Error", Messagebox.YES , null);
nameBox.focus();
return;