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riloadr.js
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riloadr.js
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/*!
* Riloadr.js 1.4.3 (c) 2013 Tubal Martin - MIT license
*/
!function(definition) {
if (typeof define === 'function' && define.amd) {
// Register as an AMD module.
define(definition);
} else {
// Browser globals
window.Riloadr = definition();
}
}(function(){
'use strict';
var ON = 'on'
, TOP = 'top'
, SRC = 'src'
, TRUE = !0
, BODY = 'body'
, LEFT = 'left'
, FALSE = !1
, DELAY = 250
, NULL = null
, LOAD = 'load'
, CALL = 'call'
, APPLY = 'apply'
, ERROR = 'error'
, WIDTH = 'width'
, EMPTYSTRING = ''
, HEIGHT = 'height'
, LENGTH = 'length'
, SCROLL = 'scroll'
, OFFSET = 'offset'
, CLIENT = 'client'
, RESIZE = 'resize'
, ONLOAD = ON+LOAD
, ONERROR = ON+ERROR
, ONABORT = ON+'abort'
, RETRIES = 'retries'
, MINWIDTH = 'minWidth'
, MAXWIDTH = 'maxWidth'
, COMPLETE = 'complete'
, RILOADED = 'riloaded'
, FALLBACK = 'fallback'
, CLASSNAME = 'className'
, IMGFORMAT = 'imgFormat'
, PROTOTYPE = 'prototype'
, UNDEFINED = 'undefined'
, SCROLLTOP = SCROLL+'Top'
, ONCOMPLETE = ON+COMPLETE
, READYSTATE = 'readyState'
, SCROLLLEFT = SCROLL+'Left'
, LOADIMAGES = LOAD+'Images'
, PAGEYOFFSET = 'pageYOffset'
, PAGEXOFFSET = 'pageXOffset'
, ORIENTATION = 'orientation'
, ATTACHEVENT = 'attachEvent'
, EVENTLISTENER = 'EventListener'
, GETELEMENTBYID = 'getElementById'
, DOCUMENTELEMENT = 'documentElement'
, READYSTATECHANGE = 'readystatechange'
, QUERYSELECTORALL = 'querySelectorAll'
, ADDEVENTLISTENER = 'add'+EVENTLISTENER
, ORIENTATIONCHANGE = ORIENTATION+'change'
, MINDEVICEPIXELRATIO = 'minDevicePixelRatio'
, GETBOUNDINGCLIENTRECT = 'getBoundingClientRect'
, body
, win = window
, doc = win.document
, docElm = doc[DOCUMENTELEMENT]
// Event model
, w3c = ADDEVENTLISTENER in doc
, pre = w3c ? EMPTYSTRING : ON
, add = w3c ? ADDEVENTLISTENER : ATTACHEVENT
, rem = w3c ? 'remove'+EVENTLISTENER : 'detachEvent'
// REGEXPS
, QUESTION_MARK_REGEX = /\?/
, BREAKPOINT_NAME_REGEX = /{breakpoint-name}/gi
// Feature support
, selectorsApiSupported = QUERYSELECTORALL in doc
, orientationSupported = ORIENTATION in win && ON+ORIENTATIONCHANGE in win
// Screen info
, viewportWidth
, screenWidth = win.screen[WIDTH]
, devicePixelRatio = win.devicePixelRatio || 1
// Bandwidth info (bool)
, hasLowBandwidth = hasLowBandwidth()
// Support for Opera Mini (executes Js on the server)
, operaMini = Object[PROTOTYPE].toString[CALL](win.operamini) === '[object OperaMini]'
// Other uninitialized vars
, onDomReady, lastOrientation;
// Remove "no-js" class from <html> element, if it exists:
docElm[CLASSNAME] = docElm[CLASSNAME].replace(/(^|\s)no-js(\s|$)/, '$1$2');
/*
* Constructor: Riloadr
* Creates a Riloadr object
* Parameters:
* options - Object containing configuration options
*/
function Riloadr(options) {
// PRIVATE PROPERTIES
// ------------------
var instance = this
// Base path
, base = options.base || EMPTYSTRING
// CSS-like breakpoints configuration (required)
, breakpoints = options.breakpoints || error('"breakpoints" not defined.')
// Group name: a name to identify images that must be processed by Riloadr.
// Specified in the 'class' attribute of 'img' tags.
, className = options.name || 'responsive'
, classNameRegexp = new RegExp('(^|\\s)'+className+'(\\s|$)')
// defer & foldDistance retro-compatibility definition
, deferObj = options.defer && (typeof options.defer == 'string' ?
{'mode': options.defer, 'threshold': options.foldDistance, 'overflownElemsIds': []} :
options.defer)
// Defer load: disabled by default. If enabled it falls back to "load".
// Possible values: 'invisible', 'belowfold' (deprecated) & 'load'.
, deferMode = deferObj && deferObj.mode.toLowerCase()
// Setting threshold to n causes image to load n pixels before it is visible.
// Falls back to 100px.
, threshold = deferObj && deferObj.threshold || 100
// Array of Overflown elements IDs that contain images only visible if user scrolls on that element
// (elements with overflow:auto or overflow(-xy):scroll CSS properties)
, overflownElemsIds = deferObj && deferObj.overflownElemsIds
// Dynamic Art direction. Intended for desktop/large screens.
// Mobile browsers cannot be resized although some of them fire the
// resize event when certain actions occur but the viewport width
// isn't likely to change so it's safe to assume this setting targets
// desktop browsers only.
// Possible values: 'wider', '*'
, watchViewportMode = options.watchViewportWidth
, watchViewportEnabled = !!watchViewportMode
, watchViewportUp = watchViewportMode == 'wider'
, watchViewportBoth = watchViewportMode == '*'
// Set to true to deliver Hi-Res images despite connection speed.
// Defaults to false, meaning connection speed is not ignored so
// Hi-Res images will only be requested if connection speed is fast enough.
, ignoreLowBandwidth = options.ignoreLowBandwidth || FALSE
// # of times to retry to load an image if initial loading failed.
// Falls back to 0 (no retries)
, retries = options[RETRIES] || 0
// Id of a DOM node where Riloadr must look for 'responsive' images.
// Falls back to body if not set.
, root = options.root || NULL
// 'invisible' defer mode? (support 'belowfold' for retro compatibility)
, deferInvisibleEnabled = (deferMode == 'invisible' || deferMode == 'belowfold') && !operaMini
// Reduce by 5.5x the # of times loadImages is called when scrolling
, scrollListener = throttle(function() {
instance[LOADIMAGES]();
}, DELAY)
// Reduce to 1 the # of times loadImages is called when resizing
, resizeListener = debounce(function() {
// On resize update viewport dependant values if watchViewport mode is enabled
watchViewportEnabled && setVwidthAndBreakpoints();
// Update image list onresize if watchViewport mode is enabled
instance[LOADIMAGES]( watchViewportEnabled );
}, DELAY)
// Reduce to 1 the # of times loadImages is called when orientation changes.
, orientationchangeListener = debounce(function(){
if (win[ORIENTATION] !== lastOrientation) {
lastOrientation = win[ORIENTATION];
instance[LOADIMAGES]();
}
}, DELAY)
// Static list (array) of images.
, images = []
// # of images not completely loaded
, imagesPendingLoad = 0
// Breakpoint that applies
, breakpoint
// Previous breakpoint used before a resize event
, prevBreakpoint
// Fallback breakpoint
, fallbackBreakpoint = {}
// Widest breakpoint from those supplied
, widestBreakpoint
// Boolean flag
, currentBreakpointIsWidest;
// PRIVATE METHODS
// ---------------
/*
* Sets viewportWidth, breakpoint, fallbackBreakpoint & currentBreakpointIsWidest vars
*/
function setVwidthAndBreakpoints() {
viewportWidth = getViewportWidthInCssPixels();
breakpoint = getBreakpoint(breakpoints, viewportWidth, ignoreLowBandwidth);
fallbackBreakpoint = breakpoint[FALLBACK] && getFallbackBreakpoint(breakpoints, breakpoint[FALLBACK]);
widestBreakpoint = widestBreakpoint || watchViewportEnabled && getWidestBreakpoint(breakpoints);
// If watch mode is enabled & is set to 'wider', test whether the current
// breakpoint is equal to the widest breakpoint.
currentBreakpointIsWidest = watchViewportUp && areBreakpointsEqual(breakpoint, widestBreakpoint);
}
/*
* Registers event listeners
* React on scroll, resize and orientationchange events
*/
function addEventListeners() {
var i = 0, current;
// Event shared by defer & watchViewport modes
if (deferInvisibleEnabled || watchViewportEnabled) {
addEvent(win, RESIZE, resizeListener);
}
if (deferInvisibleEnabled) {
addEvent(win, SCROLL, scrollListener);
// Is orientationchange event supported? If so, let's try to avoid false
// positives by checking if win.orientation has actually changed.
if (orientationSupported) {
lastOrientation = win[ORIENTATION];
addEvent(win, ORIENTATIONCHANGE, orientationchangeListener);
}
// Scroll events on overflown elements
if (overflownElemsIds) {
while (current = overflownElemsIds[i]) {
addEvent(doc[GETELEMENTBYID](current), SCROLL, scrollListener);
i++;
}
}
}
}
/*
* Removes event listeners
*/
function removeEventListeners() {
var i = 0, current;
// Only remove events if watchViewport mode is disabled/done
if ( ! watchViewportEnabled ) {
removeEvent(win, RESIZE, resizeListener);
// Only remove the scroll/orientation events if defer 'invisible' mode
// is enabled & watchViewport mode is disabled/done
if (deferInvisibleEnabled) {
removeEvent(win, SCROLL, scrollListener);
// Scroll events on overflown elements
if (overflownElemsIds) {
while (current = overflownElemsIds[i]) {
removeEvent(doc[GETELEMENTBYID](current), SCROLL, scrollListener);
i++;
}
}
// Is orientationchange event supported? If so, remove the listener
orientationSupported && removeEvent(win, ORIENTATIONCHANGE, orientationchangeListener);
}
}
}
/*
* Loads an image (DOM)
*/
function loadImage(img, idx) {
// Initial # of times we tried to reload this image
img[RETRIES] = 0;
// fallback image flag
img[FALLBACK] = FALSE;
// Register event listeners
img[ONLOAD] = imageOnloadCallback;
img[ONERROR] = img[ONABORT] = imageOnerrorCallback;
// Load it
// The first time the "src" attribute is assigned with JS, image events
// will be fired cross-browser. However, if an error occurs and we
// need to set again the "src" attribute using JS, image events might
// not be fired in some browsers such as some versions of Google Chrome.
// See imageOnerrorCallback for a workaround that works cross-browser.
img[SRC] = getImageSrc(img, base, breakpoint);
// Reduce the images array for shorter loops
images.splice(idx, 1);
}
/*
* Image onload Callback
*/
function imageOnloadCallback() {
var img = this, _img, dim;
// Avoid false positives: Some browsers may fire the "onload" image
// event after the "onerror" or "onabort" events have fired.
// Modern browsers
if ('naturalWidth' in img) {
dim = img['naturalWidth'] + img['naturalHeight'];
} else {
// Older browsers (IE < 9)
_img = new Image;
_img[SRC] = img[SRC]; // Response already cached, nevermind.
dim = _img[WIDTH] + _img[HEIGHT];
_img = NULL;
}
// Did image load correctly?
if (+dim > 0) {
img[ONLOAD] = img[ONERROR] = img[ONABORT] = NULL;
img[RILOADED] && (img[CLASSNAME] = img[CLASSNAME].replace(classNameRegexp, '$1$2'));
deferInvisibleEnabled && (img.style.visibility = 'visible');
ONLOAD in options && options[ONLOAD][CALL](img);
onCompleteCallback();
}
}
/*
* Image onerror Callback
* If user sets 'retries' > 0, Riloadr will try to load an image n times
* if an image fails to load.
*/
function imageOnerrorCallback() {
var img = this
, loadImage = function(src) {
var _img = new Image;
_img[ONLOAD] = function() {
img[SRC] = _img[SRC];
imageOnloadCallback[CALL](img);
};
_img[ONERROR] = img[ONABORT] = function() {
imageOnerrorCallback[CALL](img);
};
_img[SRC] = src;
}
, src;
// Remove event listeners from DOM image since events might not be
// fired anymore.
img[ONLOAD] = img[ONERROR] = img[ONABORT] = NULL;
ONERROR in options && options[ONERROR][CALL](img);
if (img[RETRIES] < retries) {
img[RETRIES]++;
src = getImageSrc(img, base, (img[FALLBACK] ? fallbackBreakpoint : breakpoint), TRUE);
loadImage(src);
} else if (FALLBACK in breakpoint && !img[FALLBACK]) {
img[RETRIES] = 0;
img[FALLBACK] = TRUE;
src = getImageSrc(img, base, fallbackBreakpoint);
loadImage(src);
} else {
// If an image fails to load consider it loaded.
onCompleteCallback();
}
}
/*
* oncomplete Callback
* Executes when all images in a group are 100% (down)loaded.
*/
function onCompleteCallback() {
imagesPendingLoad--;
if (imagesPendingLoad === 0) {
// No more images to load? remove event listeners
removeEventListeners();
ONCOMPLETE in options && options[ONCOMPLETE]();
}
}
// PUBLIC PRIVILEGED METHODS
// -------------------------
/*
* Collects and loads all 'responsive' images from the DOM node specified.
* If no DOM node is specified, it falls back to body.
* Notes:
* - Friendly with other scripts running.
* - Must be publicly accesible but should not be called directly.
*/
instance[LOADIMAGES] = function(update) {
// Schedule it to run after the current call stack has cleared.
defer(function(imageList, current, i) {
// If initial collection is not done or watch mode is forced or
// new images have been added to the DOM, collect them.
if (!images[LENGTH] || update === TRUE) {
// Add event listeners on update
update && addEventListeners();
imageList = selectorsApiSupported &&
root[QUERYSELECTORALL]('img.'+className) ||
root.getElementsByTagName('img');
// Create a static list
i = 0;
while (current = imageList[i]) {
// If we haven't processed this image yet and it is a responsive image
if (current && !current[RILOADED] &&
(selectorsApiSupported ||
current[CLASSNAME].indexOf(className) >= 0)) {
// Push image if:
// - Watch mode is disabled/done
// - Watch mode is enabled and it's the first breakpoint processed or
// - Watch mode 'wider' is enabled and current breakpoint is wider than previous one or
// - Watch mode '*' is enabled and current breakpoint differs from previous one
if (! watchViewportEnabled ||
watchViewportEnabled && (
! prevBreakpoint || (
watchViewportUp && isBreakpointWider(breakpoint, prevBreakpoint) ||
watchViewportBoth && ! areBreakpointsEqual(breakpoint, prevBreakpoint)
))) {
// Add image to the list
images.push(current);
// Increment counter
imagesPendingLoad++;
}
// Flag images as RILOADED if watch mode is disabled/done or
// if watch mode is 'wider' & current breakpoint matches the widest breakpoint
if ( ! watchViewportEnabled || currentBreakpointIsWidest) {
// Flag to avoid reprocessing
current[RILOADED] = TRUE;
}
}
i++;
}
if (watchViewportEnabled) {
// If watch mode is 'wider' & current breakpoint matches the widest breakpoint
// disable watch mode.
if (currentBreakpointIsWidest) {
watchViewportEnabled = FALSE;
}
// Remember the breakpoint used
prevBreakpoint = breakpoint;
}
}
// Load images
if (images[LENGTH]) {
i = 0;
while (current = images[i]) {
if (current &&
(!deferInvisibleEnabled || (deferInvisibleEnabled && isInViewport(current, threshold)))
) {
loadImage(current, i);
i--;
}
i++;
}
}
// Clean up
imageList = current = NULL;
});
};
// INITIALIZATION
// --------------
onDomReady(function(){
body = doc[BODY];
root = doc[GETELEMENTBYID](root) || body;
setVwidthAndBreakpoints();
// Add event listeners
addEventListeners();
if (!deferMode || deferInvisibleEnabled) {
// No defer mode: load all images now! OR
// 'belowfold'-'invisible' mode enabled: Load initial "visible" images
instance[LOADIMAGES]();
} else {
// defer mode = 'load': Load all images after window is loaded OR
// 'belowfold'-'invisible' not supported: 'load' fallback
onWindowReady(instance[LOADIMAGES]);
}
});
}
// PUBLIC STATIC PROPERTIES
// ------------------------
// Versioning guidelines: http://semver.org/
Riloadr.version = '1.4.3';
// PUBLIC METHODS (SHARED)
// ------------------------
/*
* The "riload" method allows you to load responsive images inserted into the
* document after the DOM is ready or after window is loaded (useful for AJAX
* content & markup created dynamically with javascript).
* Call this method after new markup is inserted into the document.
*/
Riloadr[PROTOTYPE].riload = function() {
this[LOADIMAGES](TRUE);
};
// HELPER FUNCTIONS
// ----------------
/*
* Returns the breakpoint to apply.
* Uses the viewport width to mimic CSS behavior.
*/
function getBreakpoint(breakpoints, vWidth, ignoreLowBandwidth) {
var _vWidth = vWidth
, i = 0
, breakpoint = {}
, _breakpoint, minWidth, maxWidth, minDpr;
while (_breakpoint = breakpoints[i]) {
minWidth = _breakpoint[MINWIDTH];
maxWidth = _breakpoint[MAXWIDTH];
minDpr = _breakpoint[MINDEVICEPIXELRATIO];
// Viewport width found
if (vWidth > 0) {
if (minWidth && maxWidth && vWidth >= minWidth && vWidth <= maxWidth ||
minWidth && !maxWidth && vWidth >= minWidth ||
maxWidth && !minWidth && vWidth <= maxWidth) {
if (!minDpr || minDpr && devicePixelRatio >= minDpr &&
(ignoreLowBandwidth || !ignoreLowBandwidth && !hasLowBandwidth)) {
breakpoint = _breakpoint;
}
}
// Viewport width not found so let's find the smallest image size
// (mobile first approach).
} else if (_vWidth <= 0 || minWidth < _vWidth || maxWidth < _vWidth) {
_vWidth = minWidth || maxWidth || _vWidth;
breakpoint = _breakpoint;
}
i++;
}
return breakpoint;
}
/*
* Returns the widest breakpoint from those supplied.
*/
function getWidestBreakpoint(breakpoints) {
var i = 0, widestBreakpoint = {}, current;
while (current = breakpoints[i]) {
isBreakpointWider(current, widestBreakpoint) && (widestBreakpoint = current);
i++;
}
return widestBreakpoint;
}
/*
* Returns the fallback breakpoint to apply.
*/
function getFallbackBreakpoint(breakpoints, fallbackBreakpointName) {
var i = 0, current;
while (current = breakpoints[i]) {
if (current.name == fallbackBreakpointName) {
return current;
}
i++;
}
}
/*
* Tests if two breakpoints are equal
*/
function areBreakpointsEqual(a, b) {
return a.name === b.name &&
a[MINWIDTH] === b[MINWIDTH] &&
a[MAXWIDTH] === b[MAXWIDTH] &&
a[MINDEVICEPIXELRATIO] === b[MINDEVICEPIXELRATIO] &&
a[IMGFORMAT] === b[IMGFORMAT];
}
/*
* Tests if breakpoint A is 'wider' than breakpoint B
*/
function isBreakpointWider(a, b) {
var aMinDpr = +a[MINDEVICEPIXELRATIO] || 1
, bMinDpr = +b[MINDEVICEPIXELRATIO] || 1;
a = Math.max(+a[MINWIDTH] || 0, +a[MAXWIDTH] || 0) * (devicePixelRatio >= aMinDpr ? aMinDpr : 1);
b = Math.max(+b[MINWIDTH] || 0, +b[MAXWIDTH] || 0) * (devicePixelRatio >= bMinDpr ? bMinDpr : 1);
return a > b;
}
/*
* Returns the layout viewport width in CSS pixels.
* To achieve a precise result the following meta must be included at least:
* <meta name="viewport" content="width=device-width">
* See:
* - http://www.quirksmode.org/mobile/viewports2.html
* - http://www.quirksmode.org/mobile/tableViewport.html
* - https://github.com/h5bp/mobile-boilerplate/wiki/The-Markup
*/
function getViewportWidthInCssPixels() {
var math = Math
, widths = [docElm.clientWidth, docElm.offsetWidth, body.clientWidth]
, screenWidthFallback = math.ceil(screenWidth / devicePixelRatio)
, l = widths[LENGTH]
, i = 0
, width;
for (; i < l; i++) {
// If not a number remove it
if (isNaN(widths[i])) {
widths.splice(i, 1);
i--;
}
}
if (widths[LENGTH]) {
width = math.max[APPLY](math, widths);
// Catch cases where the viewport is wider than the screen
if (!isNaN(screenWidthFallback)) {
width = math.min(screenWidthFallback, width);
}
}
return width || screenWidthFallback || 0;
}
/*
* Returns the URL of an image
* If reload is TRUE, a timestamp is added to avoid caching.
*/
function getImageSrc(img, base, breakpoint, reload) {
var src = (img.getAttribute('data-base') || base) +
(img.getAttribute('data-src') || EMPTYSTRING);
if (breakpoint[IMGFORMAT]) {
src = src.split('.');
src.pop();
src = src.join('.') + '.' + breakpoint[IMGFORMAT];
}
if (reload) {
src += (QUESTION_MARK_REGEX.test(src) ? '&' : '?') +
'riloadrts='+(new Date).getTime();
}
return src.replace(BREAKPOINT_NAME_REGEX, breakpoint.name);
}
/*
* Tells whether user's device connection is slow or not.
* Fast connection assumed if not detected or offline.
* Based on the Network Api:
* - MDN: https://developer.mozilla.org/en/DOM/window.navigator.connection
* - W3C Working draft: http://www.w3.org/TR/netinfo-api/
* - W3C Editor's draft: http://dvcs.w3.org/hg/dap/raw-file/tip/network-api/Overview.html
* List of device bandwidths: http://en.wikipedia.org/wiki/List_of_device_bandwidths#Mobile_telephone_interfaces
*/
function hasLowBandwidth() {
var navigator = win.navigator
, connection = navigator.connection || navigator.mozConnection ||
navigator.webkitConnection || navigator.oConnection ||
navigator.msConnection || {}
, type = connection.type || 'unknown' // polyfill
, bandwidth = +connection.bandwidth || Infinity; // polyfill
// 2G, 3G and KB/s < 100 are considered slow connections.
// Offline mode is considered fast connection (bandwidth = 0 or type = none).
// According to the W3C, 'bandwidth' is reported in MB/s.
// 0.09765625 MB/s = 100 KB/s = 800 kbps. Let's round up to 0.1 MB/s.
return bandwidth > 0 && bandwidth < 0.1 || /^[23]g|3|4$/.test(type + EMPTYSTRING);
}
/*
* Tells if an image is in the viewport area or not (visible to the user).
*/
function isInViewport(img, threshold) {
return !isBelowTheFold(img, threshold) && !isAboveTheTop(img, threshold) &&
!isRightOfFold(img, threshold) && !isLeftOfBegin(img, threshold);
}
function isBelowTheFold(img, threshold) {
return getDimension(HEIGHT, win) + getScroll(TOP, win) <= getOffset(TOP, img) - threshold;
}
function isAboveTheTop(img, threshold) {
return getScroll(TOP, win) >= getOffset(TOP, img) + threshold + getDimension(HEIGHT, img);
}
function isRightOfFold(img, threshold) {
return getDimension(WIDTH, win) + getScroll(LEFT, win) <= getOffset(LEFT, img) - threshold;
}
function isLeftOfBegin(img, threshold) {
return getScroll(LEFT, win) >= getOffset(LEFT, img) + threshold + getDimension(WIDTH, img);
}
/*
* Following "css" functions taken from jQuery 1.10
*/
function getOffset( name, elem ) {
var box = { top: 0, left: 0 }
, doc = elem && elem.ownerDocument
, win, offsets;
if ( !doc ) {
return;
}
if ( typeof elem[GETBOUNDINGCLIENTRECT] !== UNDEFINED ) {
box = elem[GETBOUNDINGCLIENTRECT]();
}
win = getWindow( doc );
offsets = {
top: box[TOP] + ( win[PAGEYOFFSET] || docElm[SCROLLTOP] ) - ( docElm.clientTop || 0 ),
left: box[LEFT] + ( win[PAGEXOFFSET] || docElm[SCROLLLEFT] ) - ( docElm.clientLeft || 0 )
};
return offsets[name];
}
function getScroll( name, elem ) {
var names = {
top: {method: SCROLLTOP, prop: PAGEYOFFSET},
left: {method: SCROLLLEFT, prop: PAGEXOFFSET}
}
, method = names[name].method
, prop = names[name].prop
, win = getWindow( elem );
return win ? (prop in win) ? win[ prop ] :
docElm[ method ] :
elem[ method ];
}
function getDimension( name, elem ) {
var names = { height: 'Height', width: 'Width'}
, doc, val, styles;
name = names[name];
if ( isWindow( elem ) ) {
return docElm[ CLIENT + name ];
}
// Get document width or height (not needed for Riloadr)
/*
if ( elem.nodeType === 9 ) {
doc = elem[DOCUMENTELEMENT];
// Either scroll[Width/Height] or offset[Width/Height] or client[Width/Height], whichever is greatest
// unfortunately, this causes bug #3838 in IE6/8 only, but there is currently no good, small way to fix it.
return Math.max(
elem[BODY][ SCROLL + name ], doc[ SCROLL + name ],
elem[BODY][ OFFSET + name ], doc[ OFFSET + name ],
doc[ CLIENT + name ]
);
}
*/
// Get width or height on the element
// Start with offset property, which is equivalent to the border-box value
val = elem[ OFFSET + name ];
name = name.toLowerCase();
if ( val <= 0 || val == NULL ) {
// Fall back to computed then uncomputed css if necessary
if (win.getComputedStyle) {
styles = win.getComputedStyle( elem, NULL );
} else if ( docElm.currentStyle ) {
styles = elem.currentStyle;
}
if (styles) {
val = styles[ name ];
}
if ( val < 0 || val == NULL ) {
val = elem.style[ name ];
}
}
return parseFloat( val ) || 0;
}
function isWindow( obj ) {
return obj != NULL && obj == obj.window;
}
function getWindow( elem ) {
return isWindow( elem ) ?
elem :
elem.nodeType === 9 ?
elem.defaultView || elem.parentWindow :
FALSE;
}
/*
* Thanks to underscore.js and lodash.js
* Returns a function, that, when invoked, will only be triggered at most once
* during a given window of time.
*/
function throttle(func, wait) {
var args
, result
, thisArg
, timeoutId
, lastCalled = 0;
function trailingCall() {
lastCalled = new Date;
timeoutId = NULL;
func[APPLY](thisArg, args);
}
return function() {
var now = new Date
, remain = wait - (now - lastCalled);
args = arguments;
thisArg = this;
if (remain <= 0) {
lastCalled = now;
result = func[APPLY](thisArg, args);
} else if (!timeoutId) {
timeoutId = delay(trailingCall, remain);
}
return result;
};
}
/*
* Thanks to underscore.js and lodash.js
* Returns a function, that, as long as it continues to be invoked, will not
* be triggered. The function will be called after it stops being called for
* N milliseconds. If `immediate` is passed, trigger the function on the
* leading edge, instead of the trailing.
*/
function debounce(func, wait, immediate) {
var args
, result
, thisArg
, timeoutId;
function delayed() {
timeoutId = NULL;
if (!immediate) {
func[APPLY](thisArg, args);
}
}
return function() {
var isImmediate = immediate && !timeoutId;
args = arguments;
thisArg = this;
clearTimeout(timeoutId);
timeoutId = delay(delayed, wait);
if (isImmediate) {
result = func[APPLY](thisArg, args);
}
return result;
};
}
/*
* Thanks to underscore.js and lodash.js
* Delays a function for the given number of milliseconds, and then calls
* it with the arguments supplied.
*/
function delay(func, wait) {
var args = Array[PROTOTYPE].slice[CALL](arguments, 2);
return win.setTimeout(function(){ return func[APPLY](NULL, args); }, wait);
}
/*
* Thanks to underscore.js and lodash.js
* Defers a function, scheduling it to run after the current call stack has cleared.
*/
function defer(func) {
return delay[APPLY](NULL, [func, 1].concat(Array[PROTOTYPE].slice[CALL](arguments, 1)));
}
/*
* Error reporting function
*/
function error(msg) {
throw new Error( 'Riloadr: ' + msg );
}
/*
* Simple event attachment/detachment
*/
function addEvent(elem, type, fn) {
elem[add](pre + type, fn, FALSE);
}
function removeEvent(elem, type, fn) {
elem[rem](pre + type, fn, FALSE);
}
/*
* onDomReady.js 1.3 (c) 2013 Tubal Martin - MIT license
* https://github.com/tubalmartin/ondomready
* Notes:
* - Slightly adapted for Riloadr
* - Compatible with async script loading
*/
onDomReady = (function(){
var DOMCONTENTLOADED = 'DOMContentLoaded'
, top = FALSE
// isReady: Is the DOM ready to be used? Set to true once it occurs.
, isReady = FALSE
// Callbacks pending execution until DOM is ready
, callbacks = [];
// Handle when the DOM is ready
function ready( fn ) {
if ( !isReady ) {
// Make sure body exists, at least, in case IE gets a little overzealous (ticket #5443).
if ( !doc[BODY] ) {
return defer( ready );