How buttons are used in "!"

Hello all: I would like to know how buttons (links) are implemented in this example:

  1.! (Main Page)
  2. Cliking Button Courses&Exams on the top of page it goes —>!TopicList
  3. Clicking Button Users&Groups it goes →!GroupsAndUsers
    or Clicking Button register it goes —>

a) Is this portal programed in Vaadin ? If it is ok ,
Could you write a little example code how to change Pages in this web on clicking buttons ???

Thanks in advanced,

Yes, that site has been implemented using Vaadin. You can tell because the BODY element has
class="v-generated-body […]

I don’t know the exact details of how they did it, but it looks like they’re using a
, just like in the
Vaadin Sampler

Navigator7 add-on
is what the developers of JavaBlackBelt created for handing the navigation on the site and much more.