Do not load window.onbeforeonload event if we are not on an existing nav menu. props filosofo. Reduce opacity on nav menu postboxes if we are not on an existing nav menu, and for JS users, deactivate all links and form elements, to make it obvious that those UI elements are not usable at this stage. fixes #13615

git-svn-id: http://svn.automattic.com/wordpress/trunk@15062 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/js/nav-menu.dev.js

@@ -113,6 +113,10 @@ var wpNavMenu;
 				 * @param jQuery metabox The metabox jQuery object.
 				 */
 				addSelectedToMenu : function(processMethod) {
+					if ( 0 == $('#menu-to-edit').length ) {
+						return false;
+					}
+
 					return this.each(function() {
 						var t = $(this), menuItems = {},
 							checkboxes = t.find('.tabs-panel-active .categorychecklist li input:checked'),
@@ -555,10 +559,16 @@ var wpNavMenu;
 			$('#menu-management input, #menu-management select, #menu-management, #menu-management textarea').change(function(){
 				api.registerChange();
 			});
-			window.onbeforeunload = function(){
-				if ( api.menusChanged )
-					return navMenuL10n.saveAlert;
-			};
+
+			if ( 0 != $('#menu-to-edit').length ) {
+				window.onbeforeunload = function(){
+					if ( api.menusChanged )
+						return navMenuL10n.saveAlert;
+				};
+			} else {
+				// Make the post boxes read-only, as they can't be used yet
+				$('#menu-settings-column').find('input,select').attr('disabled', 'disabled').end().find('a').attr('href', '#').unbind('click');
+			}
 		},
 
 		registerChange : function() {