lightbox.js

js 图片浏览

        this.prevLink.hide();
        this.nextLink.hide();
		// HACK: Opera9 does not currently support scriptaculous opacity and appear fx
        this.imageDataContainer.setStyle({opacity: .0001});
        this.numberDisplay.hide();      
        
        var imgPreloader = new Image();
        
        // once image is preloaded, resize image container


        imgPreloader.onload = (function(){
            this.lightboxImage.src = this.imageArray[this.activeImage][0];
            this.resizeImageContainer(imgPreloader.width, imgPreloader.height);
        }).bind(this);
        imgPreloader.src = this.imageArray[this.activeImage][0];
    },

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

        // get current width and height
        var widthCurrent  = this.outerImageContainer.getWidth();
        var heightCurrent = this.outerImageContainer.getHeight();

        // get new width and height
        var widthNew  = (imgWidth  + LightboxOptions.borderSize * 2);
        var heightNew = (imgHeight + LightboxOptions.borderSize * 2);

        // scalars based on change from old to new
        var xScale = (widthNew  / widthCurrent)  * 100;
        var yScale = (heightNew / heightCurrent) * 100;

        // calculate size difference between new and old image, and resize if necessary
        var wDiff = widthCurrent - widthNew;
        var hDiff = heightCurrent - heightNew;

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

        // if new and old image are same size and no scaling transition is necessary, 
        // do a quick pause to prevent image flicker.
        var timeout = 0;
        if ((hDiff == 0) && (wDiff == 0)){
            timeout = 100;
            if (Prototype.Browser.IE) timeout = 250;   
        }

        (function(){
            this.prevLink.setStyle({ height: imgHeight + 'px' });
            this.nextLink.setStyle({ height: imgHeight + 'px' });
            this.imageDataContainer.setStyle({ width: widthNew + 'px' });

            this.showImage();
        }).bind(this).delay(timeout / 1000);
    },
    
    //
    //  showImage()
    //  Display image and begin preloading neighbors.
    //
    showImage: function(){
        this.loading.hide();
        new Effect.Appear(this.lightboxImage, { 
            duration: this.resizeDuration, 
            queue: 'end', 
            afterFinish: (function(){ this.updateDetails(); }).bind(this) 
        });
        this.preloadNeighborImages();
    },

    //
    //  updateDetails()
    //  Display caption, image number, and bottom nav.
    //
    updateDetails: function() {
    
        // if caption is not null
        if (this.imageArray[this.activeImage][1] != ""){
            this.caption.update(this.imageArray[this.activeImage][1]).show();
        }
        
        // if image is part of set display 'Image x of x' 
        if (this.imageArray.length > 1){
            this.numberDisplay.update( LightboxOptions.labelImage + ' ' + (this.activeImage + 1) + ' ' + LightboxOptions.labelOf + '  ' + this.imageArray.length).show();
        }

        new Effect.Parallel(
            [ 
                new Effect.SlideDown(this.imageDataContainer, { sync: true, duration: this.resizeDuration, from: 0.0, to: 1.0 }), 
                new Effect.Appear(this.imageDataContainer, { sync: true, duration: this.resizeDuration }) 
            ], 
            { 
                duration: this.resizeDuration, 
                afterFinish: (function() {
	                // update overlay size and update nav
	                var arrayPageSize = this.getPageSize();
	                this.overlay.setStyle({ height: arrayPageSize[1] + 'px' });
	                this.updateNav();
                }).bind(this)
            } 
        );
    },

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

        this.hoverNav.show();               

        // if not first image in set, display prev image button
        if (this.activeImage > 0) this.prevLink.show();

        // if not last image in set, display next image button
        if (this.activeImage < (this.imageArray.length - 1)) this.nextLink.show();
        
        this.enableKeyboardNav();
    },

    //
    //  enableKeyboardNav()
    //
    enableKeyboardNav: function() {
        document.observe('keydown', this.keyboardAction); 
    },

    //
    //  disableKeyboardNav()
    //
    disableKeyboardNav: function() {
        document.stopObserving('keydown', this.keyboardAction); 
    },

    //
    //  keyboardAction()
    //
    keyboardAction: function(event) {
        var keycode = event.keyCode;

        var escapeKey;
        if (event.DOM_VK_ESCAPE) {  // mozilla
            escapeKey = event.DOM_VK_ESCAPE;
        } else { // ie
            escapeKey = 27;
        }

        var key = String.fromCharCode(keycode).toLowerCase();
        
        if (key.match(/x|o|c/) || (keycode == escapeKey)){ // close lightbox
            this.end();
        } else if ((key == 'p') || (keycode == 37)){ // display previous image
            if (this.activeImage != 0){
                this.disableKeyboardNav();
                this.changeImage(this.activeImage - 1);
            }
        } else if ((key == 'n') || (keycode == 39)){ // display next image
            if (this.activeImage != (this.imageArray.length - 1)){
                this.disableKeyboardNav();
                this.changeImage(this.activeImage + 1);
            }
        }
    },

    //
    //  preloadNeighborImages()
    //  Preload previous and next images.
    //
    preloadNeighborImages: function(){
        var preloadNextImage, preloadPrevImage;
        if (this.imageArray.length > this.activeImage + 1){
            preloadNextImage = new Image();
            preloadNextImage.src = this.imageArray[this.activeImage + 1][0];
        }
        if (this.activeImage > 0){
            preloadPrevImage = new Image();
            preloadPrevImage.src = this.imageArray[this.activeImage - 1][0];
        }
    
    },

    //
    //  end()
    //
    end: function() {
        this.disableKeyboardNav();
        this.lightbox.hide();
        new Effect.Fade(this.overlay, { duration: this.overlayDuration });
        $$('select', 'object', 'embed').each(function(node){ node.style.visibility = 'visible' });
    },

    //
    //  getPageSize()
    //
    getPageSize: function() {
	        
	     var xScroll, yScroll;
		
		if (window.innerHeight && window.scrollMaxY) {	
			xScroll = window.innerWidth + window.scrollMaxX;
			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
			if(document.documentElement.clientWidth){
				windowWidth = document.documentElement.clientWidth; 
			} else {
				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 = xScroll;		
		} else {
			pageWidth = windowWidth;
		}

		return [pageWidth,pageHeight];
	}
}

document.observe('dom:loaded', function () { new Lightbox(); });