1 files changed, 46 insertions, 32 deletions
diff --git a/skins/default/functions.js b/skins/default/functions.js
index 5d55447d6..8482e375a 100644
--- a/skins/default/functions.js
+++ b/skins/default/functions.js
@@ -570,7 +570,6 @@ function rcube_init_mail_ui()
       rcmail.addEventListener('responseaftergetunread', rcube_render_mailboxlist);
       rcmail.addEventListener('responseaftercheck-recent', rcube_render_mailboxlist);
       rcmail.addEventListener('aftercollapse-folder', rcube_render_mailboxlist);
-      rcube_render_mailboxlist();
     }
 
     if (rcmail.env.action == 'compose')
@@ -592,12 +591,16 @@ function iframe_events()
 // Abbreviate mailbox names to fit width of the container
 function rcube_render_mailboxlist()
 {
-  if (bw.ie6)  // doesn't work well on IE6
+  var list = $('#mailboxlist > li a, #mailboxlist ul:visible > li a');
+
+  // it's too slow with really big number of folders, especially on IE
+  if (list.length > 500 * (bw.ie ? 0.2 : 1))
     return;
 
-  $('#mailboxlist > li a, #mailboxlist ul:visible > li a').each(function(){
-    var elem = $(this);
-    var text = elem.data('text');
+  list.each(function(){
+    var elem = $(this),
+      text = elem.data('text');
+
     if (!text) {
       text = elem.text().replace(/\s+\(.+$/, '');
       elem.data('text', text);
@@ -615,34 +618,45 @@ function rcube_render_mailboxlist()
 // inspired by https://gist.github.com/24261/7fdb113f1e26111bd78c0c6fe515f6c0bf418af5
 function fit_string_to_size(str, elem, len)
 {
-    var result = str;
-    var ellip = '...';
-    var span = $('<b>').css({ visibility:'hidden', padding:'0px' }).appendTo(elem).get(0);
-
-    // on first run, check if string fits into the length already.
-    span.innerHTML = result;
-    if (span.offsetWidth > len) {
-        var cut = Math.max(1, Math.floor(str.length * ((span.offsetWidth - len) / span.offsetWidth) / 2)),
-          mid = Math.floor(str.length / 2);
-        var offLeft = mid, offRight = mid;
-        while (true) {
-            offLeft = mid - cut;
-            offRight = mid + cut;
-            span.innerHTML = str.substring(0,offLeft) + ellip + str.substring(offRight);
-
-            // break loop if string fits size
-            if (span.offsetWidth <= len || offLeft < 3)
-              break;
-
-            cut++;
-        }
-
-        // build resulting string
-        result = str.substring(0,offLeft) + ellip + str.substring(offRight);
+  var w, span, result = str, ellip = '...';
+
+  if (!rcmail.env.tmp_span) {
+    // it should be appended to elem to use the same css style
+    // but for performance reasons we'll append it to body (once)
+    span = $('<b>').css({visibility: 'hidden', padding: '0px'})
+      .appendTo($('body', document)).get(0);
+    rcmail.env.tmp_span = span;
+  }
+  else {
+    span = rcmail.env.tmp_span;
+  }
+  span.innerHTML = result;
+
+  // on first run, check if string fits into the length already.
+  w = span.offsetWidth;
+  if (w > len) {
+    var cut = Math.max(1, Math.floor(str.length * ((w - len) / w) / 2)),
+      mid = Math.floor(str.length / 2),
+      offLeft = mid,
+      offRight = mid;
+
+    while (true) {
+      offLeft = mid - cut;
+      offRight = mid + cut;
+      span.innerHTML = str.substring(0,offLeft) + ellip + str.substring(offRight);
+
+      // break loop if string fits size
+      if (offLeft < 3 || span.offsetWidth)
+        break;
+
+      cut++;
     }
-    
-    span.parentNode.removeChild(span);
-    return result;
+
+    // build resulting string
+    result = str.substring(0,offLeft) + ellip + str.substring(offRight);
+  }
+
+  return result;
 }
 
 // Optional parameters used by TinyMCE