https://birgittephilippides.com/cms/modules/bMenu/js/jquery.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: 2007-03-19 10:02:41 -0500 (Mon, 19 Mar 2007) $
6 * $Rev: 1546 $
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 ([email protected] || 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);