accordion: use synced animations only when animating two elements; optimize for only-one

diff --git a/ui/ui.accordion.js b/ui/ui.accordion.js
index de0ef00fdbb5eb5da62d059e2e19e0f321659fb5..30aad692ce391c9b76b500bb0e70987360712d07 100644 (file)
--- a/ui/ui.accordion.js
+++ b/ui/ui.accordion.js
@@ -410,6 +410,10 @@ $.extend($.ui.accordion, {
                                options.toShow.animate({height: "show"}, options);
                                return;
                        }
+                       if ( !options.toShow.size() ) {
+                               options.toHide.animate({height: "hide"}, options);
+                               return;
+                       }
                        var overflow = options.toShow.css('overflow'),
                                percentDone,
                                showProps = {},
@@ -417,29 +421,22 @@ $.extend($.ui.accordion, {
                                fxAttrs = [ "height", "paddingTop", "paddingBottom" ],
                                originalWidth;
                        // fix width before calculating height of hidden element
-                       if (options.toShow[0]) {
-                               var s = options.toShow;
-                               originalWidth = s[0].style.width;
-                               s.width( parseInt(s.parent().width()) - parseInt(s.css("paddingLeft")) - parseInt(s.css("paddingRight")) - parseInt(s.css("borderLeftWidth")) - parseInt(s.css("borderRightWidth")) );
-                       }
+                       var s = options.toShow;
+                       originalWidth = s[0].style.width;
+                       s.width( parseInt(s.parent().width()) - parseInt(s.css("paddingLeft")) - parseInt(s.css("paddingRight")) - parseInt(s.css("borderLeftWidth")) - parseInt(s.css("borderRightWidth")) );
+                       
                        $.each(fxAttrs, function(i, prop) {
                                hideProps[prop] = 'hide';
                                
-                               if (options.toShow[0]) {
-                                       var parts = ('' + $.css(options.toShow[0], prop)).match(/^([\d+-.]+)(.*)$/);
-                                       showProps[prop] = {
-                                               value: parts[1],
-                                               unit: parts[2] || 'px'
-                                       };
-                               }
+                               var parts = ('' + $.css(options.toShow[0], prop)).match(/^([\d+-.]+)(.*)$/);
+                               showProps[prop] = {
+                                       value: parts[1],
+                                       unit: parts[2] || 'px'
+                               };
                        });
                        options.toShow.css({ height: 0, overflow: 'hidden' }).show();
                        options.toHide.filter(":hidden").each(options.complete).end().filter(":visible").animate(hideProps,{
                                step: function(now, settings) {
-                                       // if the collapsible option is set to true, we may not have
-                                       // a content pane to show
-                                       if (!options.toShow[0]) { return; }
-                                       
                                        // only calculate the percent when animating height
                                        // IE gets very inconsistent results when animating elements
                                        // with small values, which is common for padding