alpaca
Version:
Alpaca provides the easiest and fastest way to generate interactive forms for the web and mobile devices. It runs simply as HTML5 or more elaborately using Bootstrap, jQuery Mobile or jQuery UI. Alpaca uses Handlebars to process JSON schema and provide
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JavaScript
/*! Respond.js v1.4.0: min/max-width media query polyfill. (c) Scott Jehl. MIT Lic. j.mp/respondjs */
(function( w ){
"use strict";
//exposed namespace
var respond = {};
w.respond = respond;
//define update even in native-mq-supporting browsers, to avoid errors
respond.update = function(){};
//define ajax obj
var requestQueue = [],
xmlHttp = (function() {
var xmlhttpmethod = false;
try {
xmlhttpmethod = new w.XMLHttpRequest();
}
catch( e ){
xmlhttpmethod = new w.ActiveXObject( "Microsoft.XMLHTTP" );
}
return function(){
return xmlhttpmethod;
};
})(),
//tweaked Ajax functions from Quirksmode
ajax = function( url, callback ) {
var req = xmlHttp();
if (!req){
return;
}
req.open( "GET", url, true );
req.onreadystatechange = function () {
if ( req.readyState !== 4 || req.status !== 200 && req.status !== 304 ){
return;
}
callback( req.responseText );
};
if ( req.readyState === 4 ){
return;
}
req.send( null );
};
//expose for testing
respond.ajax = ajax;
respond.queue = requestQueue;
// expose for testing
respond.regex = {
media: /@media[^\{]+\{([^\{\}]*\{[^\}\{]*\})+/gi,
keyframes: /@(?:\-(?:o|moz|webkit)\-)?keyframes[^\{]+\{(?:[^\{\}]*\{[^\}\{]*\})+[^\}]*\}/gi,
urls: /(url\()['"]?([^\/\)'"][^:\)'"]+)['"]?(\))/g,
findStyles: /@media *([^\{]+)\{([\S\s]+?)$/,
only: /(only\s+)?([a-zA-Z]+)\s?/,
minw: /\([\s]*min\-width\s*:[\s]*([\s]*[0-9\.]+)(px|em)[\s]*\)/,
maxw: /\([\s]*max\-width\s*:[\s]*([\s]*[0-9\.]+)(px|em)[\s]*\)/
};
//expose media query support flag for external use
respond.mediaQueriesSupported = w.matchMedia && w.matchMedia( "only all" ) !== null && w.matchMedia( "only all" ).matches;
//if media queries are supported, exit here
if( respond.mediaQueriesSupported ){
return;
}
//define vars
var doc = w.document,
docElem = doc.documentElement,
mediastyles = [],
rules = [],
appendedEls = [],
parsedSheets = {},
resizeThrottle = 30,
head = doc.getElementsByTagName( "head" )[0] || docElem,
base = doc.getElementsByTagName( "base" )[0],
links = head.getElementsByTagName( "link" ),
lastCall,
resizeDefer,
//cached container for 1em value, populated the first time it's needed
eminpx,
// returns the value of 1em in pixels
getEmValue = function() {
var ret,
div = doc.createElement('div'),
body = doc.body,
originalHTMLFontSize = docElem.style.fontSize,
originalBodyFontSize = body && body.style.fontSize,
fakeUsed = false;
div.style.cssText = "position:absolute;font-size:1em;width:1em";
if( !body ){
body = fakeUsed = doc.createElement( "body" );
body.style.background = "none";
}
// 1em in a media query is the value of the default font size of the browser
// reset docElem and body to ensure the correct value is returned
docElem.style.fontSize = "100%";
body.style.fontSize = "100%";
body.appendChild( div );
if( fakeUsed ){
docElem.insertBefore( body, docElem.firstChild );
}
ret = div.offsetWidth;
if( fakeUsed ){
docElem.removeChild( body );
}
else {
body.removeChild( div );
}
// restore the original values
docElem.style.fontSize = originalHTMLFontSize;
if( originalBodyFontSize ) {
body.style.fontSize = originalBodyFontSize;
}
//also update eminpx before returning
ret = eminpx = parseFloat(ret);
return ret;
},
//enable/disable styles
applyMedia = function( fromResize ){
var name = "clientWidth",
docElemProp = docElem[ name ],
currWidth = doc.compatMode === "CSS1Compat" && docElemProp || doc.body[ name ] || docElemProp,
styleBlocks = {},
lastLink = links[ links.length-1 ],
now = (new Date()).getTime();
//throttle resize calls
if( fromResize && lastCall && now - lastCall < resizeThrottle ){
w.clearTimeout( resizeDefer );
resizeDefer = w.setTimeout( applyMedia, resizeThrottle );
return;
}
else {
lastCall = now;
}
for( var i in mediastyles ){
if( mediastyles.hasOwnProperty( i ) ){
var thisstyle = mediastyles[ i ],
min = thisstyle.minw,
max = thisstyle.maxw,
minnull = min === null,
maxnull = max === null,
em = "em";
if( !!min ){
min = parseFloat( min ) * ( min.indexOf( em ) > -1 ? ( eminpx || getEmValue() ) : 1 );
}
if( !!max ){
max = parseFloat( max ) * ( max.indexOf( em ) > -1 ? ( eminpx || getEmValue() ) : 1 );
}
// if there's no media query at all (the () part), or min or max is not null, and if either is present, they're true
if( !thisstyle.hasquery || ( !minnull || !maxnull ) && ( minnull || currWidth >= min ) && ( maxnull || currWidth <= max ) ){
if( !styleBlocks[ thisstyle.media ] ){
styleBlocks[ thisstyle.media ] = [];
}
styleBlocks[ thisstyle.media ].push( rules[ thisstyle.rules ] );
}
}
}
//remove any existing respond style element(s)
for( var j in appendedEls ){
if( appendedEls.hasOwnProperty( j ) ){
if( appendedEls[ j ] && appendedEls[ j ].parentNode === head ){
head.removeChild( appendedEls[ j ] );
}
}
}
appendedEls.length = 0;
//inject active styles, grouped by media type
for( var k in styleBlocks ){
if( styleBlocks.hasOwnProperty( k ) ){
var ss = doc.createElement( "style" ),
css = styleBlocks[ k ].join( "\n" );
ss.type = "text/css";
ss.media = k;
//originally, ss was appended to a documentFragment and sheets were appended in bulk.
//this caused crashes in IE in a number of circumstances, such as when the HTML element had a bg image set, so appending beforehand seems best. Thanks to @dvelyk for the initial research on this one!
head.insertBefore( ss, lastLink.nextSibling );
if ( ss.styleSheet ){
ss.styleSheet.cssText = css;
}
else {
ss.appendChild( doc.createTextNode( css ) );
}
//push to appendedEls to track for later removal
appendedEls.push( ss );
}
}
},
//find media blocks in css text, convert to style blocks
translate = function( styles, href, media ){
var qs = styles.replace( respond.regex.keyframes, '' ).match( respond.regex.media ),
ql = qs && qs.length || 0;
//try to get CSS path
href = href.substring( 0, href.lastIndexOf( "/" ) );
var repUrls = function( css ){
return css.replace( respond.regex.urls, "$1" + href + "$2$3" );
},
useMedia = !ql && media;
//if path exists, tack on trailing slash
if( href.length ){ href += "/"; }
//if no internal queries exist, but media attr does, use that
//note: this currently lacks support for situations where a media attr is specified on a link AND
//its associated stylesheet has internal CSS media queries.
//In those cases, the media attribute will currently be ignored.
if( useMedia ){
ql = 1;
}
for( var i = 0; i < ql; i++ ){
var fullq, thisq, eachq, eql;
//media attr
if( useMedia ){
fullq = media;
rules.push( repUrls( styles ) );
}
//parse for styles
else{
fullq = qs[ i ].match( respond.regex.findStyles ) && RegExp.$1;
rules.push( RegExp.$2 && repUrls( RegExp.$2 ) );
}
eachq = fullq.split( "," );
eql = eachq.length;
for( var j = 0; j < eql; j++ ){
thisq = eachq[ j ];
mediastyles.push( {
media : thisq.split( "(" )[ 0 ].match( respond.regex.only ) && RegExp.$2 || "all",
rules : rules.length - 1,
hasquery : thisq.indexOf("(") > -1,
minw : thisq.match( respond.regex.minw ) && parseFloat( RegExp.$1 ) + ( RegExp.$2 || "" ),
maxw : thisq.match( respond.regex.maxw ) && parseFloat( RegExp.$1 ) + ( RegExp.$2 || "" )
} );
}
}
applyMedia();
},
//recurse through request queue, get css text
makeRequests = function(){
if( requestQueue.length ){
var thisRequest = requestQueue.shift();
ajax( thisRequest.href, function( styles ){
translate( styles, thisRequest.href, thisRequest.media );
parsedSheets[ thisRequest.href ] = true;
// by wrapping recursive function call in setTimeout
// we prevent "Stack overflow" error in IE7
w.setTimeout(function(){ makeRequests(); },0);
} );
}
},
//loop stylesheets, send text content to translate
ripCSS = function(){
for( var i = 0; i < links.length; i++ ){
var sheet = links[ i ],
href = sheet.href,
media = sheet.media,
isCSS = sheet.rel && sheet.rel.toLowerCase() === "stylesheet";
//only links plz and prevent re-parsing
if( !!href && isCSS && !parsedSheets[ href ] ){
// selectivizr exposes css through the rawCssText expando
if (sheet.styleSheet && sheet.styleSheet.rawCssText) {
translate( sheet.styleSheet.rawCssText, href, media );
parsedSheets[ href ] = true;
} else {
if( (!/^([a-zA-Z:]*\/\/)/.test( href ) && !base) ||
href.replace( RegExp.$1, "" ).split( "/" )[0] === w.location.host ){
// IE7 doesn't handle urls that start with '//' for ajax request
// manually add in the protocol
if ( href.substring(0,2) === "//" ) { href = w.location.protocol + href; }
requestQueue.push( {
href: href,
media: media
} );
}
}
}
}
makeRequests();
};
//translate CSS
ripCSS();
//expose update for re-running respond later on
respond.update = ripCSS;
//expose getEmValue
respond.getEmValue = getEmValue;
//adjust on resize
function callMedia(){
applyMedia( true );
}
if( w.addEventListener ){
w.addEventListener( "resize", callMedia, false );
}
else if( w.attachEvent ){
w.attachEvent( "onresize", callMedia );
}
})(this);