www/prive/javascript/bgiframe.js

   1 /* Copyright (c) 2006 Brandon Aaron (http://brandonaaron.net)
   2  * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
   3  * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
   4  *
   5  * $LastChangedDate$
   6  * $Rev$
   7  */
   8
   9 (function($){
  10
  11 /**
  12  * The bgiframe is chainable and applies the iframe hack to get
  13  * around zIndex issues in IE6. It will only apply itself in IE
  14  * and adds a class to the iframe called 'bgiframe'. The iframe
  15  * is appeneded as the first child of the matched element(s)
  16  * with a tabIndex and zIndex of -1.
  17  *
  18  * By default the plugin will take borders, sized with pixel units,
  19  * into account. If a different unit is used for the border's width,
  20  * then you will need to use the top and left settings as explained below.
  21  *
  22  * NOTICE: This plugin has been reported to cause perfromance problems
  23  * when used on elements that change properties (like width, height and
  24  * opacity) a lot in IE6. Most of these problems have been caused by
  25  * the expressions used to calculate the elements width, height and
  26  * borders. Some have reported it is due to the opacity filter. All
  27  * these settings can be changed if needed as explained below.
  28  *
  29  * @example $('div').bgiframe();
  30  * @before <div><p>Paragraph</p></div>
  31  * @result <div><iframe class="bgiframe".../><p>Paragraph</p></div>
  32  *
  33  * @param Map settings Optional settings to configure the iframe.
  34  * @option String|Number top The iframe must be offset to the top
  35  *              by the width of the top border. This should be a negative
  36  *      number representing the border-top-width. If a number is
  37  *              is used here, pixels will be assumed. Otherwise, be sure
  38  *              to specify a unit. An expression could also be used.
  39  *              By default the value is "auto" which will use an expression
  40  *              to get the border-top-width if it is in pixels.
  41  * @option String|Number left The iframe must be offset to the left
  42  *              by the width of the left border. This should be a negative
  43  *      number representing the border-left-width. If a number is
  44  *              is used here, pixels will be assumed. Otherwise, be sure
  45  *              to specify a unit. An expression could also be used.
  46  *              By default the value is "auto" which will use an expression
  47  *              to get the border-left-width if it is in pixels.
  48  * @option String|Number width This is the width of the iframe. If
  49  *              a number is used here, pixels will be assume. Otherwise, be sure
  50  *              to specify a unit. An experssion could also be used.
  51  *              By default the value is "auto" which will use an experssion
  52  *              to get the offsetWidth.
  53  * @option String|Number height This is the height of the iframe. If
  54  *              a number is used here, pixels will be assume. Otherwise, be sure
  55  *              to specify a unit. An experssion could also be used.
  56  *              By default the value is "auto" which will use an experssion
  57  *              to get the offsetHeight.
  58  * @option Boolean opacity This is a boolean representing whether or not
  59  *              to use opacity. If set to true, the opacity of 0 is applied. If
  60  *              set to false, the opacity filter is not applied. Default: true.
  61  * @option String src This setting is provided so that one could change
  62  *              the src of the iframe to whatever they need.
  63  *              Default: "javascript:false;"
  64  *
  65  * @name bgiframe
  66  * @type jQuery
  67  * @cat Plugins/bgiframe
  68  * @author Brandon Aaron (brandon.aaron@gmail.com || http://brandonaaron.net)
  69  */
  70 $.fn.bgIframe = jQuery.fn.bgiframe = function(s) {
  71         // This is only for IE6
  72         if ( !($.browser.msie && typeof XMLHttpRequest == 'function') ) return this;
  73         s = $.extend({
  74                 top     : 'auto', // auto == .currentStyle.borderTopWidth
  75                 left    : 'auto', // auto == .currentStyle.borderLeftWidth
  76                 width   : 'auto', // auto == offsetWidth
  77                 height  : 'auto', // auto == offsetHeight
  78                 opacity : true,
  79                 src     : 'javascript:false;'
  80         }, s || {});
  81         var prop = function(n){return n&&n.constructor==Number?n+'px':n;},
  82             html = '<iframe class="bgiframe"frameborder="0"tabindex="-1"src="'+s.src+'"'+
  83                        'style="display:block;position:absolute;z-index:-1;'+
  84                                (s.opacity !== false?'filter:Alpha(Opacity=\'0\');':'')+
  85                                        'top:'+(s.top=='auto'?'expression(((parseInt(this.parentNode.currentStyle.borderTopWidth)||0)*-1)+\'px\')':prop(s.top))+';'+
  86                                        'left:'+(s.left=='auto'?'expression(((parseInt(this.parentNode.currentStyle.borderLeftWidth)||0)*-1)+\'px\')':prop(s.left))+';'+
  87                                        'width:'+(s.width=='auto'?'expression(this.parentNode.offsetWidth+\'px\')':prop(s.width))+';'+
  88                                        'height:'+(s.height=='auto'?'expression(this.parentNode.offsetHeight+\'px\')':prop(s.height))+';'+
  89                                 '"/>';
  90         return this.each(function() {
  91                 if ( !$('iframe.bgiframe', this)[0] )
  92                         this.insertBefore( document.createElement(html), this.firstChild );
  93         });
  94 };
  95
  96 })(jQuery);