Changeset 24005

Timestamp:

04/16/2013 10:35:55 PM (13 years ago)

Author:

lancewillett

Message:

Twenty Thirteen: further performance for functions.js scroll event callback, props obenland. See #23875.

Location:

trunk/wp-content/themes/twentythirteen

Files:

• functions.php (modified) (1 diff)
• js/functions.js (modified) (2 diffs)

trunk/wp-content/themes/twentythirteen/functions.php

@@ -224 +224 @@
 
         // Loads JavaScript file with functionality specific to Twenty Thirteen.
-        wp_enqueue_script( 'twentythirteen-script', get_template_directory_uri() . '/js/functions.js', array( 'jquery' ), '20130211', true );
+        wp_enqueue_script( 'twentythirteen-script', get_template_directory_uri() . '/js/functions.js', array( 'jquery' ), '20130416', true );
 
         // Loads our main stylesheet.

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

@@ -6 +6 @@
 
 ( function( $ ) {
-        var html          = $( 'html' ),
-            body          = $( 'body' ),
-            navbar        = $( '#navbar' ),
-            _window       = $( window ),
-            navbarOffset  = -1,
-            toolbarOffset = body.is( '.admin-bar' ) ? 28 : 0,
+        var html               = $( 'html' ),
+            body               = $( 'body' ),
+            navbar             = $( '#navbar' ),
+            _window            = $( window ),
+            toolbarOffset      = body.is( '.admin-bar' ) ? 28 : 0,
+            navbarOffset       = navbar.offset().top - toolbarOffset,
+            scrollOffsetMethod = ( typeof window.scrollY === 'undefined' ),
             adjustFooter,
             adjustAnchor;
@@ -49 +50 @@
          * Displays the fixed navbar based on screen position.
          */
-        _window.on( 'scroll.twentythirteen', function() {
-                var scrollOffset = ( typeof window.scrollY === 'undefined' ) ? document.documentElement.scrollTop : window.scrollY;
-                if ( navbarOffset < 0 )
-                        navbarOffset = navbar.offset().top - toolbarOffset;
-
-                if ( scrollOffset >= navbarOffset && _window.innerWidth() > 644 )
-                        html.addClass( 'navbar-fixed' );
-                else
-                        html.removeClass( 'navbar-fixed' );
-        } );
+        if ( _window.innerWidth() > 644 ) {
+                _window.on( 'scroll.twentythirteen', function() {
+                        var scrollOffset = scrollOffsetMethod ? document.documentElement.scrollTop : window.scrollY;
+        
+                        if ( scrollOffset > navbarOffset )
+                                html.addClass( 'navbar-fixed' );
+                        else
+                                html.removeClass( 'navbar-fixed' );
+                } );
+        }
 
         /**