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wizard04wsu/_IE 6 PNG fix

Created February 19, 2014 15:03
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IE 6 PNG fix
Raw
_IE 6 PNG fix
This fixes the transparency of PNG images in IE 6, for both image elements and background image styles.
This also requires a 1-pixel transparent GIF "blank.gif" in the same directory as "iepngfix.htc".
Put the HTML below into <head>, make sure the path to "iepngfix.htc" is correct, and apply it to specific elements instead of everything.
<!--[if lte IE 6]>
<style type="text/css" media="all">
* { behavior:url(/css/iepngfix.htc); } /*IE 6 PNG fix*/
</style>
<![endif]-->
Raw
iepngfix.htc
<public:component>
<script type="text/javascript">
// IE5.5+ PNG Alpha Fix v2.0 Alpha
// (c) 2004-2009 Angus Turnbull http://www.twinhelix.com
// This is licensed under the GNU LGPL, version 2.1 or later.
// For details, see: http://creativecommons.org/licenses/LGPL/2.1/
var IEPNGFix = window.IEPNGFix || {};
IEPNGFix.data = IEPNGFix.data || {};
// CONFIG: blankImg is the path to blank.gif, *relative to the HTML document*.
// Try either:
// * An absolute path like: '/images/blank.gif'
// * A path relative to this HTC file like: thisFolder + 'blank.gif'
var thisFolder = document.URL.replace(/(\\|\/)[^\\\/]*$/, '/');
IEPNGFix.blankImg = thisFolder + 'blank.gif';
IEPNGFix.fix = function(elm, src, t) {
// Applies an image 'src' to an element 'elm' using the DirectX filter.
// If 'src' is null, filter is disabled.
// Disables the 'hook' to prevent infinite recursion on setting BG/src.
// 't' = type, where background tile = 0, background = 1, IMG SRC = 2.
var h = this.hook.enabled;
this.hook.enabled = 0;
var f = 'DXImageTransform.Microsoft.AlphaImageLoader';
src = (src || '').replace(/\(/g, '%28').replace(/\)/g, '%29');
if (
src && !(/IMG|INPUT/.test(elm.nodeName) && (t != 2)) &&
elm.currentStyle.width == 'auto' && elm.currentStyle.height == 'auto'
) {
if (elm.offsetWidth) {
elm.style.width = elm.offsetWidth + 'px';
}
if (elm.clientHeight) {
elm.style.height = elm.clientHeight + 'px';
}
if (elm.currentStyle.display == 'inline') {
elm.style.display = 'inline-block';
}
}
if (t == 1) {
elm.style.backgroundImage = 'url("' + this.blankImg + '")';
}
if (t == 2) {
elm.src = this.blankImg;
}
if (elm.filters[f]) {
elm.filters[f].enabled = src ? true : false;
if (src) {
elm.filters[f].src = src;
}
} else if (src) {
elm.style.filter = 'progid:' + f + '(src="' + src +
'",sizingMethod="' + (t == 2 ? 'scale' : 'crop') + '")';
}
this.hook.enabled = h;
};
IEPNGFix.process = function(elm, init) {
// Checks the onpropertychange event (on first 'init' run, a fake event)
// and calls the filter-applying-functions.
if (
!/MSIE (5\.5|6)/.test(navigator.userAgent) ||
typeof elm.filters == 'unknown'
) {
return;
}
if (!this.data[elm.uniqueID]) {
this.data[elm.uniqueID] = {
className: ''
};
}
var data = this.data[elm.uniqueID],
evt = init ? { propertyName: 'src,backgroundImage' } : event,
isSrc = /src/.test(evt.propertyName),
isBg = /backgroundImage/.test(evt.propertyName),
isPos = /width|height|background(Pos|Rep)/.test(evt.propertyName),
isClass = !init && ((elm.className != data.className) &&
(elm.className || data.className));
if (!(isSrc || isBg || isPos || isClass)) {
return;
}
data.className = elm.className;
var blank = this.blankImg.match(/([^\/]+)$/)[1],
eS = elm.style,
eCS = elm.currentStyle;
// Required for Whatever:hover - erase set BG if className changes.
if (
isClass && (eS.backgroundImage.indexOf('url(') == -1 ||
eS.backgroundImage.indexOf(blank) > -1)
) {
return setTimeout(function() {
eS.backgroundImage = '';
}, 0);
}
// Foregrounds.
if (isSrc && elm.src && { IMG: 1, INPUT: 1 }[elm.nodeName]) {
if ((/\.png/i).test(elm.src)) {
if (!elm.oSrc) {
// MM rollover compat
elm.oSrc = elm.src;
}
this.fix(elm, elm.src, 2);
} else if (elm.src.indexOf(blank) == -1) {
this.fix(elm, '');
}
}
// Backgrounds.
var bgSrc = eCS.backgroundImage || eS.backgroundImage;
if ((bgSrc + elm.src).indexOf(blank) == -1) {
var bgPNG = bgSrc.match(/url[("']+(.*\.png[^\)"']*)[\)"']/i);
if (bgPNG) {
if (this.tileBG && !{ IMG: 1, INPUT: 1 }[elm.nodeName]) {
this.tileBG(elm, bgPNG[1]);
this.fix(elm, '', 1);
} else {
if (data.tiles && data.tiles.src) {
this.tileBG(elm, '');
}
this.fix(elm, bgPNG[1], 1);
this.childFix(elm);
}
} else {
if (data.tiles && data.tiles.src) {
this.tileBG(elm, '');
}
this.fix(elm, '');
}
} else if ((isPos || isClass) && data.tiles && data.tiles.src) {
this.tileBG(elm, data.tiles.src);
}
if (init) {
this.hook.enabled = 1;
elm.attachEvent('onpropertychange', this.hook);
}
};
IEPNGFix.childFix = function(elm) {
// "hasLayout" fix for unclickable children inside PNG backgrounds.
var tags = [
'a',
'input',
'select',
'textarea',
'button',
'iframe',
'object'
],
t = tags.length,
tFix = [];
while (t--) {
var pFix = elm.all.tags(tags[t]),
e = pFix.length;
while (e--) {
tFix.push(pFix[e]);
}
}
t = tFix.length;
if (t && (/relative|absolute/i).test(elm.currentStyle.position)) {
alert('IEPNGFix: Unclickable children of element:' +
'\n\n<' + elm.nodeName + (elm.id && ' id=' + elm.id) + '>');
}
while (t--) {
if (!(/relative|absolute/i).test(tFix[t].currentStyle.position)) {
tFix[t].style.position = 'relative';
}
}
};
IEPNGFix.hook = function() {
if (IEPNGFix.hook.enabled) {
IEPNGFix.process(element, 0);
}
};
IEPNGFix.process(element, 1);
</script>
</public:component>
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