Add missing menu documentation, resolve #96

docs/menu.rst

@@ -0,0 +1,81 @@
+
+.. _menu:
+
+====
+Menu
+====
+
+.. php:namespace:: atk4\ui
+.. php:class:: Menu
+
+Menu implements horizontal or vertical multi-level menu by using Semantic UI's 'menu'.
+
+Using Menu
+==========
+
+.. php:method: addItem($label, $action)
+
+Here is a simple usage::
+
+    $menu = $layout->add('Menu');
+    $menu->addItem('foo');
+    $menu->addItem('bar');
+
+to make menu vertical::
+
+    $menu->addClass('vertical');
+
+
+Decorating Menu Items
+=====================
+
+See :php:class:`Item` for more options::
+
+    $menu->addItem(['foo', 'icon'=>'book']);
+
+Specifying Links and Actions
+============================
+
+Menu items can use links and actions::
+
+    $menu->addItem('foo', 'test.php');
+    $menu->addItem('bar', new jsModal('Test'));
+
+Creating sub-menus
+==================
+
+.. php:method: addMenu($label)
+.. php:method: addGroup($label)
+.. php:method: addRightMenu($label)
+
+You can create sub-menu for either vertical or horizontal menu. For a vertical
+menu you can also use groups. For horizontal menu, you can use addRightMenu.
+
+::
+
+    $menu = $layout->add('Menu');
+    $menu->addItem('foo');
+    $sub = $menu->addMenu('Some Bars');
+    $sub->addItem('bar 1');
+    $sub->addItem('bar 2');
+
+Headers
+=======
+
+.. php:method: addHeader($label)
+
+Advanced Use
+============
+
+You can add other elements inside menu. Refer to demos/menu.php.
+
+Item
+====
+
+.. php:class:: Item
+
+.. php:attr:: $label
+
+.. php::attr:: $icon
+
+Additionally you can use :php:meth:`View::addClass()` to disable or style your menu items.