Ticket #31527: 31527.twentythirteen.patch

wp-content/themes/twentythirteen/js/functions.js

@@ -6 +6 @@
 
 ( function( $ ) {
         var body    = $( 'body' ),
-            _window = $( window );
+            _window = $( window ),
+                nav, button, menu, tertiary;
 
+        nav = $( '#site-navigation' );
+        button = nav.find( '.menu-toggle' );
+        menu = nav.find( '.nav-menu' );
+        tertiary = $( '#tertiary' );
+
         /**
          * Adds a top margin to the footer if the sidebar widget area is higher
          * than the rest of the page, to help the footer always visually clear
@@ -29 +35 @@
          * Enables menu toggle for small screens.
          */
         ( function() {
-                var nav = $( '#site-navigation' ), button, menu;
-                if ( ! nav ) {
+                if ( ! nav || ! button ) {
                         return;
                 }
 
-                button = nav.find( '.menu-toggle' );
-                if ( ! button ) {
-                        return;
-                }
-
                 // Hide button if menu is missing or empty.
-                menu = nav.find( '.nav-menu' );
                 if ( ! menu || ! menu.children().length ) {
                         button.hide();
                         return;
@@ -69 +68 @@
                 } );
         } )();
 
+        // Add or remove ARIA attributes.
+        function onResizeARIA() {
+                if ( 643 > _window.width() ) {
+                        button.attr( 'aria-expanded', 'false' );
+                        tertiary.attr( 'aria-expanded', 'false' );
+                        button.attr( 'aria-controls', 'secondary' );
+                } else {
+                        button.removeAttr( 'aria-expanded' );
+                        tertiary.removeAttr( 'aria-expanded' );
+                        button.removeAttr( 'aria-controls' );
+                }
+        }
+
+        _window
+                .on( 'load.twentythirteen', onResizeARIA )
+                .on( 'resize.twentythirteen', function() {
+                        onResizeARIA();
+        } );
+
         /**
          * Makes "skip to content" link work correctly in IE9 and Chrome for better
          * accessibility.