title: select and deselect check on listgrid
body: <p>I get the next code a listgrid with the firs column is a check:</p>
  
  <pre><code>private ListGrid listGrid = new ListGrid();
  ....
  ....
  listGrid.setSelectionAppearance(SelectionAppearance.CHECKBOX);
      listGrid .addClickHandler(new ClickHandler() {
          @Override
          public void onClick(ClickEvent event) {
              //TODO
          }
      });
  </code></pre>
  
  <p>I would like select or deselect the check component on my listgrid on the fly when a row is clicked.</p>
  
  <p>How can I do it?</p>