Ticket #6187: 6187_3.patch

_source/core/_bootstrap.js

@@ -66 +66 @@
                 }
         });
 
-/*
-TODO: Enable the following and check if effective.
-
+// Needed for IE6 to not request image (HTTP 200 or 304) for every CSS background. (#6187)
 if ( CKEDITOR.env.ie )
 {
         // Remove IE mouse flickering on IE6 because of background images.
@@ -82 +80 @@
                 // line. For safety, let's just ignore errors.
         }
 }
-*/
 
 /**
  * Fired when a CKEDITOR core object is fully loaded and ready for interaction.

_source/core/skins.js

@@ -55 +55 @@
                 }
 
                 // Check if we need to preload images from it.
-                if ( !preloaded[ skinName ] )
-                {
-                        var preload = skinDefinition.preload;
-                        if ( preload && preload.length > 0 )
-                        {
+                var preload = skinDefinition.preload;
+                if ( preload && preload.length > 0 )
+                {
+                        if ( !preloaded[ skinName ] )
+                        {
+                                // Prepare image URLs
                                 appendSkinPath( preload );
-                                CKEDITOR.imageCacher.load( preload, function()
-                                        {
-                                                preloaded[ skinName ] = 1;
+
+                                // Get preloader event dispatcher object.
+                                preloaded[ skinName ] = CKEDITOR.imageCacher.load( preload );
+                        }
+
+                        if ( !preloaded[ skinName ].finished )
+                        {
+                                // Bind listener for this editor instance.
+                                preloaded[ skinName ].on( 'preloaded', function()
+                                        {
                                                 loadPart( editor, skinName, part, callback );
-                                        } );
-                                return;
-                        }
+                                        }
+                                );
 
-                        // Mark it as preloaded.
-                        preloaded[ skinName ] = 1;
-                }
+                                // Execution will be continued from event listener.
+                                return;
+                        }
+                }
 
                 // Get the part definition.
                 part = skinDefinition[ part ];

_source/skins/v2/skin.js

@@ -7 +7 @@
 {
         var preload = [];
 
-        if ( CKEDITOR.env.ie && CKEDITOR.env.version < 7 )
-        {
-                // For IE6, we need to preload some images, otherwhise they will be
-                // downloaded several times (CSS background bug).
-                preload.push( 'icons.png', 'images/sprites_ie6.png', 'images/dialog_sides.gif' );
-        }
-
         return {
                 preload         : preload,
                 editor          : { css : [ 'editor.css' ] },

_source/skins/office2003/skin.js

@@ -7 +7 @@
 {
         var preload = [];
 
-        if ( CKEDITOR.env.ie && CKEDITOR.env.version < 7 )
-        {
-                // For IE6, we need to preload some images, otherwhise they will be
-                // downloaded several times (CSS background bug).
-                preload.push( 'icons.png', 'images/sprites_ie6.png', 'images/dialog_sides.gif' );
-        }
-
         return {
                 preload         : preload,
                 editor          : { css : [ 'editor.css' ] },

_source/core/loader.js

@@ -59 +59 @@
                         'core/htmlparser/cdata'         : [ 'core/htmlparser' ],
                         'core/htmlparser/filter'        : [ 'core/htmlparser' ],
                         'core/htmlparser/basicwriter': [ 'core/htmlparser' ],
-                        'core/imagecacher'              : [ 'core/dom/element' ],
+                        'core/imagecacher'              : [ 'core/dom/element', 'core/event' ],
                         'core/lang'                             : [],
                         'core/plugins'                  : [ 'core/resourcemanager' ],
                         'core/resourcemanager'  : [ 'core/scriptloader', 'core/tools' ],

_source/skins/kama/skin.js

@@ -8 +8 @@
         var preload = [],
                 uiColorStylesheetId = 'cke_ui_color';
 
-        if ( CKEDITOR.env.ie && CKEDITOR.env.version < 7 )
-        {
-                // For IE6, we need to preload some images, otherwhise they will be
-                // downloaded several times (CSS background bug).
-                preload.push( 'icons.png', 'images/sprites_ie6.png', 'images/dialog_sides.gif' );
-        }
-
         return {
                 preload         : preload,
                 editor          : { css : [ 'editor.css' ] },

_source/core/imagecacher.js

@@ -32 +32 @@
                 /**
                  * Loads one or more images.
                  * @param {Array} images The URLs for the images to be loaded.
-                 * @param {Function} callback The function to be called once all images
-                 *              are loaded.
+                 * @param {Function} callback The optional function to be called once all images
+                 *              are loaded. You can bind any function to the returned event object.
+                 * @return {CKEDITOR.event} Event object which fires 'preloaded' event when all images finished.
+                 *    Additionally it set "finished" property flag after 'preloaded' event.
                  */
                 load : function( images, callback )
                 {
                         var pendingCount = images.length;
 
+                        var event = new CKEDITOR.event;
+                        event.on( 'preloaded', function()
+                        {
+                                event.finished = true;
+                        });
+                        
+                        if ( callback )
+                                event.on( 'preloaded', callback );
+
                         var checkPending = function()
                         {
                                 if ( --pendingCount === 0 )
-                                        callback();
+                                        event.fire( 'preloaded' );
                         };
 
                         for ( var i = 0 ; i < images.length ; i++ )
@@ -54 +65 @@
                                 else
                                         loadImage( image, checkPending );
                         }
+
+                        return event;
                 }
         };
 })();