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@mattsnider
Created December 14, 2012 19:55
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YUI 2.x version of the super simple image viewer
(function(w, d) {
// simple function to get element by ID
var _getEl = YAHOO.util.Dom.get;
/**
* Instantiation function for the SimpleImageViewer.
* @param elImage {String|Element} Required. The ID or element instance for the image element to be updated.
* @param conf {Object} Optional. Additional configuration options:
* caption - The ID or element instance for the caption element to be updated.
* defaultGroup - The label for your default group of images. If you have just one collection of images,
* just leave this blank.
* next - The ID or element instance for the element to trigger changing to the next image.
* previous - The ID or element instance for the element to trigger changing to the previous image.
* timeout - The number of milliseconds between changing the image, when using the autoplay feature.
* Although, `next` and `previous` are optional, you will probably want to include them, or users won't be
* able to move through your images.
* @constructor
*/
function SimpleImageViewer(elImage, conf) {
var that = this;
if (!conf) {
conf = {};
}
that.boolInit = false;
that.sDefaultGroup = conf.defaultGroup || 'group0';
that.sCurrentGroup = that.sDefaultGroup;
that.elCaption = _getEl(conf.caption);
that.elNext = _getEl(conf.next);
that.elPrevious = _getEl(conf.previous);
that.elImage = _getEl(elImage);
that.nIndex = 0;
that.nIntervalId = 0;
that.nIntervalTimeout = conf.timeout || 3000;
that.oPhotos = {};
that.oPhotos[that.sDefaultGroup] = [];
// handle next click
if (that.elNext) {
YAHOO.util.Event.on(that.elNext, 'click', function(e) {
e.preventDefault();
that.next();
});
}
// handle previous click
if (that.elPrevious) {
YAHOO.util.Event.on(that.elPrevious, 'click', function(e) {
e.preventDefault();
that.previous();
});
}
}
SimpleImageViewer.prototype = {
/**
* Adds a photo to the object. By default all images are added to a single
* @param sPhotoPath {String} Required. The path to this photo.
* @param opts {Object} Optional. Additional data and organizational options:
* alt - Alternative copy for accessibility (will use caption, if not provided).
* caption - A caption for this photo.
* group - Use groups to organize photos into collections. The SimpleImageViewer will be able to navigate
* through one collection at a time. Most people just have a single collection, but this allows you
* to organize your images. You will need to manually call changeGroup(sGroupName) to switch between image
* groups.
*/
addPhoto: function(sPhotoPath, opts) {
var sAlt = '',
sCaption = '',
sGroup = this.sDefaultGroup, // default group for a single group of images
oImage,
aPhotos;
if (opts) {
sAlt = opts.alt || opts.caption || sAlt;
sCaption = opts.caption || sCaption;
sGroup = opts.group || sGroup;
}
aPhotos = this.oPhotos[sGroup] || [];
oImage = new Image();
oImage.src = sPhotoPath;
aPhotos.push({alt: sAlt, caption: sCaption, img: oImage});
this.oPhotos[sGroup] = aPhotos;
if (! this.boolInit) {
this.boolInit = true;
this.updateImage();
}
},
/**
* Change to a different collection of photos.
* @param sChangeGroup {String} Required. The group name to change to.
*/
changeGroup: function(sChangeGroup) {
this.nIndex = 0;
this.sCurrentGroup = sChangeGroup;
this.updateImage();
},
/**
* Move to the next image in the current group.
*/
next: function() {
this.nIndex += 1;
this.updateImage();
if (this.nIntervalId) {
this.stop();
this.play();
}
},
/**
* Start the autoplay feature. You can control the timeout by setting the `timeout` configuration option
* when instantiating the SimpleImageViewer object.
*/
play: function() {
var that = this;
if (!that.nIntervalId) {
this.nIntervalId = setInterval(function() {
that.nIndex += 1;
that.updateImage();
}, that.nIntervalTimeout);
}
},
/**
* Move to the previous image in the current group.
*/
previous: function() {
this.nIndex -= 1;
this.updateImage();
if (this.nIntervalId) {
this.stop();
this.play();
}
},
/**
* Stop the autoplay feature.
*/
stop: function() {
clearInterval(this.nIntervalId);
this.nIntervalId = 0;
},
/**
* Called when the source of the image element needs to change.
*/
updateImage: function() {
var aImages = this.oPhotos[this.sCurrentGroup],
oImage;
// no images in this photo group
if (! (aImages && aImages.length)) {
alert('No images available in group=' + this.sCurrentGroup);
}
// went too far previous, move to end of array
if (0 > this.nIndex) {
this.nIndex = aImages.length - 1;
}
// went too far forward, move to head of array
if (this.nIndex >= aImages.length) {
this.nIndex = 0;
}
oImage = aImages[this.nIndex];
this.elImage.src = oImage.img.src;
// update alternative copy
if (oImage.alt) {
this.elImage.alt = oImage.alt;
}
if (this.elCaption) {
this.elCaption.innerHTML = oImage.caption;
}
}
};
w.SimpleImageViewer = SimpleImageViewer;
}(window, document));
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