respond.proxy.js
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/*! Respond.js: min/max-width media query polyfill. Remote proxy (c) Scott Jehl. MIT/GPLv2 Lic. j.mp/respondjs */
(function(win, doc, undefined){
var docElem = doc.documentElement,
proxyURL = doc.getElementById("respond-proxy").href,
redirectURL = (doc.getElementById("respond-redirect") || location).href,
baseElem = doc.getElementsByTagName("base")[0],
urls = [],
refNode;
function encode(url){
return win.encodeURIComponent(url);
}
function fakejax( url, callback ){
var iframe,
AXO;
// All hail Google http://j.mp/iKMI19
// Behold, an iframe proxy without annoying clicky noises.
if ( "ActiveXObject" in win ) {
AXO = new ActiveXObject( "htmlfile" );
AXO.open();
AXO.write( '<iframe id="x"></iframe>' );
AXO.close();
iframe = AXO.getElementById( "x" );
} else {
iframe = doc.createElement( "iframe" );
iframe.style.cssText = "position:absolute;top:-99em";
docElem.insertBefore(iframe, docElem.firstElementChild || docElem.firstChild );
}
iframe.src = checkBaseURL(proxyURL) + "?url=" + encode(redirectURL) + "&css=" + encode(checkBaseURL(url));
function checkFrameName() {
var cssText;
try {
cssText = iframe.contentWindow.name;
}
catch (e) { }
if (cssText) {
// We've got what we need. Stop the iframe from loading further content.
iframe.src = "about:blank";
iframe.parentNode.removeChild(iframe);
iframe = null;
// Per http://j.mp/kn9EPh, not taking any chances. Flushing the ActiveXObject
if (AXO) {
AXO = null;
if (win.CollectGarbage) {
win.CollectGarbage();
}
}
callback(cssText);
}
else{
win.setTimeout(checkFrameName, 100);
}
}
win.setTimeout(checkFrameName, 500);
}
// http://stackoverflow.com/a/472729
function checkBaseURL(href) {
var el = document.createElement('div'),
escapedURL = href.split('&').join('&').
split('<').join('<').
split('"').join('"');
el.innerHTML = '<a href="' + escapedURL + '">x</a>';
return el.firstChild.href;
}
function checkRedirectURL() {
// IE6 & IE7 don't build out absolute urls in <link /> attributes.
// So respond.proxy.gif remains relative instead of http://example.com/respond.proxy.gif.
// This trickery resolves that issue.
if (~ !redirectURL.indexOf(location.host)) {
var fakeLink = doc.createElement("div");
fakeLink.innerHTML = '<a href="' + redirectURL + '"></a>';
docElem.insertBefore(fakeLink, docElem.firstElementChild || docElem.firstChild );
// Grab the parsed URL from that dummy object
redirectURL = fakeLink.firstChild.href;
// Clean up
fakeLink.parentNode.removeChild(fakeLink);
fakeLink = null;
}
}
function buildUrls(){
var links = doc.getElementsByTagName( "link" );
for( var i = 0, linkl = links.length; i < linkl; i++ ){
var thislink = links[i],
href = links[i].href,
extreg = (/^([a-zA-Z:]*\/\/(www\.)?)/).test( href ),
ext = (baseElem && !extreg) || extreg;
//make sure it's an external stylesheet
if( thislink.rel.indexOf( "stylesheet" ) >= 0 && ext ){
(function( link ){
fakejax( href, function( css ){
link.styleSheet.rawCssText = css;
respond.update();
} );
})( thislink );
}
}
}
if( !respond.mediaQueriesSupported ){
checkRedirectURL();
buildUrls();
}
})( window, document );