Trying to add grid in dialog window.
data added to grid, but not displaying

hoping for your advise

Code:
final ListStore<UserInfo> userListStore = new ListStore<UserInfo>();


    userListStore.add(userList);


    setSize(500, 500);


    MessageBox.info("testUSERLISTSTORE", Integer.toString(userListStore.getCount()), new Listener<MessageBoxEvent>() {
      public void handleEvent(MessageBoxEvent be) {


      }
    });


    ColumnConfig password = new ColumnConfig("password", "Pas", 100);


    ColumnConfig fullname = new ColumnConfig ("fullNameField1", "Name of User", 200) ;


    List<ColumnConfig> configs = new ArrayList<ColumnConfig>();


    configs.add(fullname);


    configs.add(password);


    ColumnModel cm = new ColumnModel(configs);


    final Grid<UserInfo> UserListGrid = new Grid<UserInfo> (userListStore, cm) ;


    UserListGrid.getView().setForceFit(true);


    add(UserListGrid);


    UserListGrid.setAutoExpandColumn("fullNameField1");


    UserListGrid.getView().ensureVisible(5,5, true);






    MessageBox.info("testGRID", Integer.toString(UserListGrid.getStore().getCount()), new Listener<MessageBoxEvent>() {


      public void handleEvent(MessageBoxEvent be) {


      }
    });


    setTitle("UserList");