For many applications using the Menu control to centralize application navigation is very useful. Menus are defined in a WEB-INF/menu.xml file which is very easy to change.

A menu is typically defined in the a page border template so they are available through out the application. The Menu control does not support HTML rendering, so you need to define a Velocity macro to programmatically render the menu. You would call the macro in your border template with code like this:

An advantage of using a macro to render your menu is that you can reuse the code across different applications, and to modify an applications menu you simply need to edit the WEB-INF/menu.xml file. A good place to define your macros is in the webroot /macro.vm file as it is automatically included by Click.

Using macros you can create dynamic menu behaviour such as only rendering menu items a user is authorized to access with isUserInRoles().

You can also use JavaScript to add dynamic behaviour such as drop down menus, for example see the Menu page in Click Examples.