Ticket #30692: 30692.patch

src/wp-admin/js/common.js

@@ -193 +193 @@
                 lastScrollPosition = 0,
                 pinnedMenuTop = false,
                 pinnedMenuBottom = false,
+                isScrolling = false,
+                scrollTimer,
                 menuTop = 0,
                 height = {
+                        document: $document.height(),
                         window: $window.height(),
                         wpwrap: $wpwrap.height(),
                         adminbar: $adminbar.height(),
@@ -554 +557 @@
                 }
 
                 if ( height.menu + height.adminbar > height.window ) {
+                        if ( windowPos < 1 || windowPos + height.window > height.document - 1 ) {
+                                return;
+                        }
+
                         if ( windowPos > lastScrollPosition ) {
                                 // Scrolling down
                                 if ( pinnedMenuTop ) {
@@ -626 +633 @@
                 lastScrollPosition = windowPos;
         }
 
+        function resetHeights() {
+                height = {
+                        document: $document.height(),
+                        window: $window.height(),
+                        wpwrap: $wpwrap.height(),
+                        adminbar: $adminbar.height(),
+                        menu: $adminMenuWrap.height()
+                };
+        }
+
         function unpinMenu() {
                 if ( isIOS ) {
                         return;
@@ -640 +657 @@
         }
 
         function setPinMenu() {
+                resetHeights();
+
                 if ( $adminmenu.data('wp-responsive') ) {
                         $body.removeClass( 'sticky-menu' );
                         unpinMenu();
@@ -652 +671 @@
                 }
         }
 
+        function scrollStart() {
+                if ( isScrolling ) {
+                        window.clearTimeout( scrollTimer );
+
+                        scrollTimer = window.setTimeout( function() {
+                                isScrolling = false;
+                        }, 200 );
+                } else {
+                        isScrolling = true;
+                        $document.triggerHandler( 'wp-scroll-start' );
+                }
+        }
+
         if ( ! isIOS ) {
-                $window.on( 'scroll.pin-menu', pinMenu );
+                $window.on( 'scroll.pin-menu', function() {
+                        scrollStart();
+                        pinMenu();
+                });
         }
 
         window.wpResponsive = {
@@ -792 +827 @@
         window.wpResponsive.init();
         setPinMenu();
 
-        $document.on( 'wp-window-resized.pin-menu postboxes-columnchange.pin-menu postbox-toggled.pin-menu', function() {
-                height.wpwrap = $wpwrap.height();
-                height.window = $window.height();
-                height.adminbar = $adminbar.height();
-                setPinMenu();
-        }).on( 'wp-collapse-menu.pin-menu', function() {
-                height.wpwrap = $wpwrap.height();
-                height.menu = $adminMenuWrap.height();
-                setPinMenu();
-        });
-
+        $document.on( 'wp-window-resized.pin-menu postboxes-columnchange.pin-menu postbox-toggled.pin-menu wp-collapse-menu.pin-menu wp-scroll-start.pin-menu', setPinMenu );
 });
 
 // Fire a custom jQuery event at the end of window resize