lightbox.js

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// -----------------------------------------------------------------------------------
//
//	Lightbox v2.03.3
//	by Lokesh Dhakar - http://www.huddletogether.com
//	5/21/06
//
//	For more information on this script, visit:
//	http://huddletogether.com/projects/lightbox2/
//
//	Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
//	
//	Credit also due to those who have helped, inspired, and made their code available to the public.
//	Including: Scott Upton(uptonic.com), Peter-Paul Koch(quirksmode.com), Thomas Fuchs(mir.aculo.us), and others.
//
//
// -----------------------------------------------------------------------------------
/*

	Table of Contents
	-----------------
	Configuration
	Global Variables

	Extending Built-in Objects	
	- Object.extend(Element)
	- Array.prototype.removeDuplicates()
	- Array.prototype.empty()

	Lightbox Class Declaration
	- initialize()
	- updateImageList()
	- start()
	- changeImage()
	- resizeImageContainer()
	- showImage()
	- updateDetails()
	- updateNav()
	- enableKeyboardNav()
	- disableKeyboardNav()
	- keyboardAction()
	- preloadNeighborImages()
	- end()
	
	Miscellaneous Functions
	- getPageScroll()
	- getPageSize()
	- getKey()
	- listenKey()
	- showSelectBoxes()
	- hideSelectBoxes()
	- showFlash()
	- hideFlash()
	- pause()
	- initLightbox()
	
	Function Calls
	- addLoadEvent(initLightbox)
	
*/
// -----------------------------------------------------------------------------------

//
//	Configuration
//
var fileLoadingImage = "/images/loading.gif";		
var fileBottomNavCloseImage = "/images/closelabel.gif";

var overlayOpacity = 0.8;	// controls transparency of shadow overlay

var animate = true;			// toggles resizing animations
var resizeSpeed = 7;		// controls the speed of the image resizing animations (1=slowest and 10=fastest)

var borderSize = 10;		//if you adjust the padding in the CSS, you will need to update this variable

// -----------------------------------------------------------------------------------

//
//	Global Variables
//
var imageArray = new Array;
var activeImage;

if(animate == true){
	overlayDuration = 0.2;	// shadow fade in/out duration
	if(resizeSpeed > 10){ resizeSpeed = 10;}
	if(resizeSpeed < 1){ resizeSpeed = 1;}
	resizeDuration = (11 - resizeSpeed) * 0.15;
} else { 
	overlayDuration = 0;
	resizeDuration = 0;
}

// -----------------------------------------------------------------------------------

//
//	Additional methods for Element added by SU, Couloir
//	- further additions by Lokesh Dhakar (huddletogether.com)
//
Object.extend(Element, {
	getWidth: function(element) {
	   	element = $(element);
	   	return element.offsetWidth; 
	},
	setWidth: function(element,w) {
	   	element = $(element);
    	element.style.width = w +"px";
	},
	setHeight: function(element,h) {
   		element = $(element);
    	element.style.height = h +"px";
	},
	setTop: function(element,t) {
	   	element = $(element);
    	element.style.top = t +"px";
	},
	setLeft: function(element,l) {
	   	element = $(element);
    	element.style.left = l +"px";
	},
	setSrc: function(element,src) {
    	element = $(element);
    	element.src = src; 
	},
	setHref: function(element,href) {
    	element = $(element);
    	element.href = href; 
	},
	setInnerHTML: function(element,content) {
		element = $(element);
		element.innerHTML = content;
	}
});

// -----------------------------------------------------------------------------------

//
//	Extending built-in Array object
//	- array.removeDuplicates()
//	- array.empty()
//
Array.prototype.removeDuplicates = function () {
    for(i = 0; i < this.length; i++){
        for(j = this.length-1; j>i; j--){        
            if(this[i][0] == this[j][0]){
                this.splice(j,1);
            }
        }
    }
}

// -----------------------------------------------------------------------------------

Array.prototype.empty = function () {
	for(i = 0; i <= this.length; i++){
		this.shift();
	}
}

// -----------------------------------------------------------------------------------

//
//	Lightbox Class Declaration
//	- initialize()
//	- start()
//	- changeImage()
//	- resizeImageContainer()
//	- showImage()
//	- updateDetails()
//	- updateNav()
//	- enableKeyboardNav()
//	- disableKeyboardNav()
//	- keyboardNavAction()
//	- preloadNeighborImages()
//	- end()
//
//	Structuring of code inspired by Scott Upton (http://www.uptonic.com/)
//
var Lightbox = Class.create();

Lightbox.prototype = {
	
	// initialize()
	// Constructor runs on completion of the DOM loading. Calls updateImageList and then
	// the function inserts html at the bottom of the page which is used to display the shadow 
	// overlay and the image container.
	//
	initialize: function() {	
		
		this.updateImageList();

		// Code inserts html at the bottom of the page that looks similar to this:
		//
		//	<div id="overlay"></div>
		//	<div id="lightbox">
		//		<div id="outerImageContainer">
		//			<div id="imageContainer">
		//				<img id="lightboxImage">
		//				<div style="" id="hoverNav">
		//					<a href="#" id="prevLink"></a>
		//					<a href="#" id="nextLink"></a>
		//				</div>
		//				<div id="loading">
		//					<a href="#" id="loadingLink">
		//						<img src="images/loading.gif">
		//					</a>
		//				</div>
		//			</div>
		//		</div>
		//		<div id="imageDataContainer">
		//			<div id="imageData">
		//				<div id="imageDetails">
		//					<span id="caption"></span>
		//					<span id="numberDisplay"></span>
		//				</div>
		//				<div id="bottomNav">
		//					<a href="#" id="bottomNavClose">
		//						<img src="images/close.gif">
		//					</a>
		//				</div>
		//			</div>
		//		</div>
		//	</div>


		var objBody = document.getElementsByTagName("body").item(0);
		
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		objOverlay.style.display = 'none';
		objOverlay.onclick = function() { myLightbox.end(); }
		objBody.appendChild(objOverlay);
		
		var objLightbox = document.createElement("div");
		objLightbox.setAttribute('id','lightbox');
		objLightbox.style.display = 'none';
		objLightbox.onclick = function(e) {	// close Lightbox is user clicks shadow overlay
			if (!e) var e = window.event;
			var clickObj = Event.element(e).id;
			if ( clickObj == 'lightbox') {
				myLightbox.end();
			}
		};
		objBody.appendChild(objLightbox);
			
		var objOuterImageContainer = document.createElement("div");
		objOuterImageContainer.setAttribute('id','outerImageContainer');
		objLightbox.appendChild(objOuterImageContainer);

		// When Lightbox starts it will resize itself from 250 by 250 to the current image dimension.
		// If animations are turned off, it will be hidden as to prevent a flicker of a
		// white 250 by 250 box.
		if(animate){
			Element.setWidth('outerImageContainer', 250);
			Element.setHeight('outerImageContainer', 250);			
		} else {
			Element.setWidth('outerImageContainer', 1);
			Element.setHeight('outerImageContainer', 1);			
		}

		var objImageContainer = document.createElement("div");
		objImageContainer.setAttribute('id','imageContainer');
		objOuterImageContainer.appendChild(objImageContainer);
	
		var objLightboxImage = document.createElement("img");
		objLightboxImage.setAttribute('id','lightboxImage');
		objImageContainer.appendChild(objLightboxImage);
	
		var objHoverNav = document.createElement("div");
		objHoverNav.setAttribute('id','hoverNav');
		objImageContainer.appendChild(objHoverNav);
	
		var objPrevLink = document.createElement("a");
		objPrevLink.setAttribute('id','prevLink');
		objPrevLink.setAttribute('href','#');
		objHoverNav.appendChild(objPrevLink);
		
		var objNextLink = document.createElement("a");
		objNextLink.setAttribute('id','nextLink');
		objNextLink.setAttribute('href','#');
		objHoverNav.appendChild(objNextLink);
	
		var objLoading = document.createElement("div");
		objLoading.setAttribute('id','loading');
		objImageContainer.appendChild(objLoading);
	
		var objLoadingLink = document.createElement("a");
		objLoadingLink.setAttribute('id','loadingLink');
		objLoadingLink.setAttribute('href','#');
		objLoadingLink.onclick = function() { myLightbox.end(); return false; }
		objLoading.appendChild(objLoadingLink);
	
		var objLoadingImage = document.createElement("img");
		objLoadingImage.setAttribute('src', fileLoadingImage);
		objLoadingLink.appendChild(objLoadingImage);

		var objImageDataContainer = document.createElement("div");
		objImageDataContainer.setAttribute('id','imageDataContainer');
		objLightbox.appendChild(objImageDataContainer);

		var objImageData = document.createElement("div");
		objImageData.setAttribute('id','imageData');
		objImageDataContainer.appendChild(objImageData);
	
		var objImageDetails = document.createElement("div");
		objImageDetails.setAttribute('id','imageDetails');
		objImageData.appendChild(objImageDetails);
	
		var objCaption = document.createElement("span");
		objCaption.setAttribute('id','caption');
		objImageDetails.appendChild(objCaption);
	
		var objNumberDisplay = document.createElement("span");
		objNumberDisplay.setAttribute('id','numberDisplay');
		objImageDetails.appendChild(objNumberDisplay);
		
		var objBottomNav = document.createElement("div");
		objBottomNav.setAttribute('id','bottomNav');
		objImageData.appendChild(objBottomNav);
	
		var objBottomNavCloseLink = document.createElement("a");
		objBottomNavCloseLink.setAttribute('id','bottomNavClose');
		objBottomNavCloseLink.setAttribute('href','#');
		objBottomNavCloseLink.onclick = function() { myLightbox.end(); return false; }
		objBottomNav.appendChild(objBottomNavCloseLink);
	
		var objBottomNavCloseImage = document.createElement("img");
		objBottomNavCloseImage.setAttribute('src', fileBottomNavCloseImage);
		objBottomNavCloseLink.appendChild(objBottomNavCloseImage);
	},


	//
	// updateImageList()
	// Loops through anchor tags looking for 'lightbox' references and applies onclick
	// events to appropriate links. You can rerun after dynamically adding images w/ajax.
	//
	updateImageList: function() {	
		if (!document.getElementsByTagName){ return; }
		var anchors = document.getElementsByTagName('a');
		var areas = document.getElementsByTagName('area');

		// loop through all anchor tags
		for (var i=0; i<anchors.length; i++){
			var anchor = anchors[i];
			
			var relAttribute = String(anchor.getAttribute('rel'));
			
			// use the string.match() method to catch 'lightbox' references in the rel attribute
			if (anchor.getAttribute('href') && (relAttribute.toLowerCase().match('lightbox'))){
				anchor.onclick = function () {myLightbox.start(this); return false;}
			}
		}

		// loop through all area tags
		// todo: combine anchor & area tag loops
		for (var i=0; i< areas.length; i++){
			var area = areas[i];
			
			var relAttribute = String(area.getAttribute('rel'));
			
			// use the string.match() method to catch 'lightbox' references in the rel attribute
			if (area.getAttribute('href') && (relAttribute.toLowerCase().match('lightbox'))){
				area.onclick = function () {myLightbox.start(this); return false;}
			}
		}
	},
	
	
	//
	//	start()
	//	Display overlay and lightbox. If image is part of a set, add siblings to imageArray.
	//
	start: function(imageLink) {	

		hideSelectBoxes();
		hideFlash();

		// stretch overlay to fill page and fade in
		var arrayPageSize = getPageSize();
		Element.setWidth('overlay', arrayPageSize[0]);
		Element.setHeight('overlay', arrayPageSize[1]);

		new Effect.Appear('overlay', { duration: overlayDuration, from: 0.0, to: overlayOpacity });

		imageArray = [];
		imageNum = 0;		

		if (!document.getElementsByTagName){ return; }
		var anchors = document.getElementsByTagName( imageLink.tagName);

		// if image is NOT part of a set..
		if((imageLink.getAttribute('rel') == 'lightbox')){
			// add single image to imageArray
			imageArray.push(new Array(imageLink.getAttribute('href'), imageLink.getAttribute('title')));			
		} else {
		// if image is part of a set..

			// loop through anchors, find other images in set, and add them to imageArray
			for (var i=0; i<anchors.length; i++){
				var anchor = anchors[i];
				if (anchor.getAttribute('href') && (anchor.getAttribute('rel') == imageLink.getAttribute('rel'))){
					imageArray.push(new Array(anchor.getAttribute('href'), anchor.getAttribute('title')));
				}
			}
			imageArray.removeDuplicates();
			while(imageArray[imageNum][0] != imageLink.getAttribute('href')) { imageNum++;}
		}

		// calculate top and left offset for the lightbox