title: Don't close PopupMenu on MenuItem-Click
body: <p>I need to show a few items in a popup menu. They are dynamically downloaded and added to PopupMenu which is shown on button's click.</p>
  
  <pre><code>        PopupMenu popupMenu = new PopupMenu(this, view);
          Menu menu = popupMenu.getMenu();
  
          for (Category c : categories) {
              menu.add(c.getName()).setCheckable(true);
          }
  
          popupMenu.show();
  </code></pre>
  
  <p>I enabled the possibility to check or uncheck the items, but I want that the user can check or uncheck more then just one item. At the moment this is not possible, because the PopupMenu is closed as the user clicks on an item.</p>
  
  <p>Has anybody done this before or has an idea to achieve my demand?</p>