lightbox.js

Zomplog is an easy to use weblog application which uses php and MySQL

		// calculate top offset for the lightbox and display 
		var arrayPageSize = getPageSize();
		var arrayPageScroll = getPageScroll();
		var lightboxTop = arrayPageScroll[1] + (arrayPageSize[3] / 15);

		Element.setTop('lightbox', lightboxTop);
		Element.show('lightbox');
		
		this.changeImage(imageNum);
	},

	//
	//	changeImage()
	//	Hide most elements and preload image in preparation for resizing image container.
	//
	changeImage: function(imageNum) {	
		
		activeImage = imageNum;	// update global var

		// hide elements during transition
		Element.show('loading');
		Element.hide('lightboxImage');
		Element.hide('hoverNav');
		Element.hide('prevLink');
		Element.hide('nextLink');
		Element.hide('imageDataContainer');
		Element.hide('numberDisplay');		
		
		imgPreloader = new Image();
		
		// once image is preloaded, resize image container
		imgPreloader.onload=function(){
			Element.setSrc('lightboxImage', imageArray[activeImage][0]);
			myLightbox.resizeImageContainer(imgPreloader.width, imgPreloader.height);
		}
		imgPreloader.src = imageArray[activeImage][0];
	},

	//
	//	resizeImageContainer()
	//
	resizeImageContainer: function( imgWidth, imgHeight) {

		// get current height and width
		this.wCur = Element.getWidth('outerImageContainer');
		this.hCur = Element.getHeight('outerImageContainer');

		// scalars based on change from old to new
		this.xScale = ((imgWidth  + (borderSize * 2)) / this.wCur) * 100;
		this.yScale = ((imgHeight  + (borderSize * 2)) / this.hCur) * 100;

		// calculate size difference between new and old image, and resize if necessary
		wDiff = (this.wCur - borderSize * 2) - imgWidth;
		hDiff = (this.hCur - borderSize * 2) - imgHeight;

		if(!( hDiff == 0)){ new Effect.Scale('outerImageContainer', this.yScale, {scaleX: false, duration: resizeDuration, queue: 'front'}); }
		if(!( wDiff == 0)){ new Effect.Scale('outerImageContainer', this.xScale, {scaleY: false, delay: resizeDuration, duration: resizeDuration}); }

		// if new and old image are same size and no scaling transition is necessary, 
		// do a quick pause to prevent image flicker.
		if((hDiff == 0) && (wDiff == 0)){
			if (navigator.appVersion.indexOf("MSIE")!=-1){ pause(250); } else { pause(100);} 
		}

		Element.setHeight('prevLink', imgHeight);
		Element.setHeight('nextLink', imgHeight);
		Element.setWidth( 'imageDataContainer', imgWidth + (borderSize * 2));

		this.showImage();
	},
	
	//
	//	showImage()
	//	Display image and begin preloading neighbors.
	//
	showImage: function(){
		Element.hide('loading');
		new Effect.Appear('lightboxImage', { duration: 0.5, queue: 'end', afterFinish: function(){	myLightbox.updateDetails(); } });
		this.preloadNeighborImages();
	},

	//
	//	updateDetails()
	//	Display caption, image number, and bottom nav.
	//
	updateDetails: function() {
	
		Element.show('caption');
		Element.setInnerHTML( 'caption', imageArray[activeImage][1]);
		
		// if image is part of set display 'Image x of x' 
		if(imageArray.length > 1){
			Element.show('numberDisplay');
			Element.setInnerHTML( 'numberDisplay', "Image " + eval(activeImage + 1) + " of " + imageArray.length);
		}

		new Effect.Parallel(
			[ new Effect.SlideDown( 'imageDataContainer', { sync: true, duration: resizeDuration + 0.25, from: 0.0, to: 1.0 }), 
			  new Effect.Appear('imageDataContainer', { sync: true, duration: 1.0 }) ], 
			{ duration: 0.65, afterFinish: function() { myLightbox.updateNav();} } 
		);
	},

	//
	//	updateNav()
	//	Display appropriate previous and next hover navigation.
	//
	updateNav: function() {

		Element.show('hoverNav');				

		// if not first image in set, display prev image button
		if(activeImage != 0){
			Element.show('prevLink');
			document.getElementById('prevLink').onclick = function() {
				myLightbox.changeImage(activeImage - 1); return false;
			}
		}

		// if not last image in set, display next image button
		if(activeImage != (imageArray.length - 1)){
			Element.show('nextLink');
			document.getElementById('nextLink').onclick = function() {
				myLightbox.changeImage(activeImage + 1); return false;
			}
		}
		
		this.enableKeyboardNav();
	},

	//
	//	enableKeyboardNav()
	//
	enableKeyboardNav: function() {
		document.onkeydown = this.keyboardAction; 
	},

	//
	//	disableKeyboardNav()
	//
	disableKeyboardNav: function() {
		document.onkeydown = '';
	},

	//
	//	keyboardAction()
	//
	keyboardAction: function(e) {
		if (e == null) { // ie
			keycode = event.keyCode;
		} else { // mozilla
			keycode = e.which;
		}

		key = String.fromCharCode(keycode).toLowerCase();
		
		if((key == 'x') || (key == 'o') || (key == 'c')){	// close lightbox
			myLightbox.end();
		} else if(key == 'p'){	// display previous image
			if(activeImage != 0){
				myLightbox.disableKeyboardNav();
				myLightbox.changeImage(activeImage - 1);
			}
		} else if(key == 'n'){	// display next image
			if(activeImage != (imageArray.length - 1)){
				myLightbox.disableKeyboardNav();
				myLightbox.changeImage(activeImage + 1);
			}
		}


	},

	//
	//	preloadNeighborImages()
	//	Preload previous and next images.
	//
	preloadNeighborImages: function(){

		if((imageArray.length - 1) > activeImage){
			preloadNextImage = new Image();
			preloadNextImage.src = imageArray[activeImage + 1][0];
		}
		if(activeImage > 0){
			preloadPrevImage = new Image();
			preloadPrevImage.src = imageArray[activeImage - 1][0];
		}
	
	},

	//
	//	end()
	//
	end: function() {
		this.disableKeyboardNav();
		Element.hide('lightbox');
		new Effect.Fade('overlay', { duration: 0.2});
		showSelectBoxes();
	}
}

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

//
// getPageScroll()
// Returns array with x,y page scroll values.
// Core code from - quirksmode.org
//
function getPageScroll(){

	var yScroll;

	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScroll = document.documentElement.scrollTop;
	} else if (document.body) {// all other Explorers
		yScroll = document.body.scrollTop;
	}

	arrayPageScroll = new Array('',yScroll) 
	return arrayPageScroll;
}

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

//
// getPageSize()
// Returns array with page width, height and window width, height
// Core code from - quirksmode.org
// Edit for Firefox by pHaez
//
function getPageSize(){
	
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = document.body.scrollWidth;
		yScroll = window.innerHeight + window.scrollMaxY;
	} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
		xScroll = document.body.scrollWidth;
		yScroll = document.body.scrollHeight;
	} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
		xScroll = document.body.offsetWidth;
		yScroll = document.body.offsetHeight;
	}
	
	var windowWidth, windowHeight;
	if (self.innerHeight) {	// all except Explorer
		windowWidth = self.innerWidth;
		windowHeight = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
		windowWidth = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body) { // other Explorers
		windowWidth = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
	}	
	
	// for small pages with total height less then height of the viewport
	if(yScroll < windowHeight){
		pageHeight = windowHeight;
	} else { 
		pageHeight = yScroll;
	}

	// for small pages with total width less then width of the viewport
	if(xScroll < windowWidth){	
		pageWidth = windowWidth;
	} else {
		pageWidth = xScroll;
	}


	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
}

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

//
// getKey(key)
// Gets keycode. If 'x' is pressed then it hides the lightbox.
//
function getKey(e){
	if (e == null) { // ie
		keycode = event.keyCode;
	} else { // mozilla
		keycode = e.which;
	}
	key = String.fromCharCode(keycode).toLowerCase();
	
	if(key == 'x'){
	}
}

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

//
// listenKey()
//
function listenKey () {	document.onkeypress = getKey; }
	
// ---------------------------------------------------

function showSelectBoxes(){
	selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}
}

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

function hideSelectBoxes(){
	selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "hidden";
	}
}

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

//
// pause(numberMillis)
// Pauses code execution for specified time. Uses busy code, not good.
// Code from http://www.faqts.com/knowledge_base/view.phtml/aid/1602
//
function pause(numberMillis) {
	var now = new Date();
	var exitTime = now.getTime() + numberMillis;
	while (true) {
		now = new Date();
		if (now.getTime() > exitTime)
			return;
	}
}

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



function initLightbox() { myLightbox = new Lightbox(); }
Event.observe(window, 'load', initLightbox, false);