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Webcomic Navigation Using Javascript?

I'm building my new webcomics home on my website and have ran smack into a wall.
Here's what I want and what I've tried.
I'm trying to have something where using JavaScript I can make only the image of the comic change so that I do not have to make a new page for every single image. I don't mind having to do extra coding work as long as I don't have hundreds of pages in my directory.
I was going to have a /First Next Prev Last/ kind of navigation but I've been so frustrated with it that I kind of scrapped that idea for now and instead am thinking of having a list of the names + link of each comic below the image and just put that into a scroll box. Kinda like how Perry Bible Fellowship works.
I've been trying to figure out if maybe an array is the way to go as I have around 30 images so far and I will be updating daily. Honestly I don't even know if Javascript is the way to go either.
I've also tried to implement [this code](http://interestingwebs.blogspot.com/2012/09/change-image-onclick-with-javascript.html
) to see if it would work and it just seems to break as soon as I try to plug in my own stuff into it. Here's an example of my javascript butcher job:
<script language="javascript">
function Drpepper()
{
document.getElementById("image").src = "/comics/1DrPepper.jpg";
}
function Applestore()
{
document.getElementById("image").src = "/comics/2Applestore.jpg";
}
</script>
<p>
<img alt="Dr Pepper" src="1DrPepper.jpg"
style="height: 85px; width: 198px" id="image" /></p>
<p>
<input id="Button1" type="button" value="Dr Pepper" onclick="DrPepper()"/>
<input id="Button2" type="button" value="Apple Store" onclick="Applestore()" /></p>
Is there anyway to expand this for my purposes? What I would like is to not have buttons and just use links but I can't seem to get beyond this part here where the image doesn't even load and the buttons do nothing.
Also if there is some better way of doing this using any other method other than JavaScript, I'm more than open to it, except the aforementioned making hundreds of pages.

First off, consider using jQuery if you're going to go the Javascript route. Here's an example I mocked up for you:
// set up an array of comic images
var imgs = [
'http://dustinland.com/dlands/dland.sxsw.jpg',
'http://dustinland.com/dlands/dland.hipster.jpg',
'http://dustinland.com/dlands/dland.legalize.marijuana.jpg',
'http://dustinland.com/dlands/dland.TLDR.jpg'
],
// initialize current to 0
current = 0;
// define a function that returns the next item in the imgs array,
// or the first if we're already at the last one
function next() {
current++;
if (current >= imgs.length) current = 0;
return imgs[current];
}
// define a function to do the opposite of next()
function prev() {
current--;
if (current < 0) current = imgs.length - 1;
return imgs[current];
}
// define the first image in terms of a jquery object
var comic = $('<img/>').attr('src', imgs[0]);
// append to DOM
$('#comics').append(comic);
// click the prev button, get the previous image
$('#prev').on('click', function(){
comic.attr('src', prev());
});
// click the next button, get the next image
$('#next').on('click', function(){
comic.attr('src', next());
});
See this in action here: http://jsfiddle.net/QzWV5/
This may work fine for your application, but maybe you should consider the advice of #icktoofay; using Javascript will mean, at the very least, that Google won't automatically crawl all your images. This also presents a usability problem: do you want to force your users to click through every comic in order to reach the first? It's probably best if every image were reachable via its own URL, that way, anyone who came across your comic on the web could easily link to an individual comic.
Have you considered using Tumblr, Blogger, or Wordpress?

How do I abort image <img> load requests without using window.stop()

I have a very long page that dynamically loads images as users scroll through.
However, if a user quickly scrolls away from a certain part of the page, I don't want the images to continue loading in that now out-of-view part of the page.
There are lots of other requests happening on the page simultaneously apart from image loading, so a blunt window.stop() firing on the scroll event is not acceptable.
I have tried removing & clearing the img src attributes for images that are no longer in view, however, since the request was already started, the image continues to load.
Remember that the image src was filled in as the user briefly scrolled past that part of the page. Once past though, I couldn't get that image from stop loading without using window.stop(). Clearing src didn't work. (Chrome & FF)
Similar posts I found that get close, but don't seem to solve this problem:
Stop loading of images with javascript (lazyload)?
Javascript: Cancel/Stop Image Requests
How to cancel an image from loading

What you are trying to do is the wrong approach, as mentioned by nrabinowitz. You can't just "cancel" the loading process of an image (setting the src attribute to an empty string is not a good idea). In fact, even if you could, doing so would only make things worst, as your server would continually send data that would get cancelled, increasing it's load factor and slow it down. Also, consider this:
if your user scroll frenetically up and down the page, he/she will expect some loading delays.
having a timeout delay (ex: 200 ms) before starting to load a portion of the page is pretty acceptable, and how many times will one stop and jump after 200 ms interval on your page? Even it it happens, it comes back to point 1
how big are your images? Even a slow server can serve about a few tens of 3Kb thunbnails per second. If your site has bigger images, consider using low and hi resolution images with some components like lightBox
Often, computer problems are simply design problems.
** EDIT **
Here's an idea :
your page should display DIV containers with the width and height of the expected image size (use CSS to style). Inside of each DIV, add an link. For example :
<div class="img-wrapper thumbnail">
Loading...
</div>
Add this Javascript (untested, the idea is self describing)
$(function() {
var imgStack;
var loadTimeout;
$(window).scroll(function() {
imgStack = null;
if (loadTimeout) clearTimeout(loadTimeout);
loadTimeout = setTimeout(function() {
// get all links visible in the view port
// should be an array or jQuery object
imgStack = ...
loadNextImage();
}, 200); // 200 ms delay
});
function loadNextImage() {
if (imgStack && imgStack.length) {
var nextLink = $(imgStack.pop()); // get next image element
$('<img />').attr('src', nextLink.attr('href'))
.appendTo(nextLink.parent())
.load(function() {
loadNextImage();
});
// remove link from container (so we don't precess it twice)
nextLink.remove();
}
};
});

Well, my idea:
1) initiate an AJAX request for the image, if it succeeds, the image goes to the browser cache, and once you set the 'src' attribute, the image is shown from the cache
2) you can abort the XHR
I wrote a tiny server with express emulating the huge image download (it actually just waits 20 seconds, then returns an image). Then I have this in my HTML:
<!DOCTYPE html>
<html>
<head>
<style>
img {
width: 469px;
height: 428px;
background-color: #CCC;
border: 1px solid #999;
}
</style>
</head>
<body>
<img data-src="./img" src="" />
<br />
<a id="cancel" href="javascript:void(0)">CANCEL</a>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
<script>
$(function () {
var xhr, img = $('img'), src = img.data('src');
xhr = $.ajax(src, {
success: function (data) { img.attr('src', src) }
});
$('#cancel').click(function (){
xhr.abort();
})
});
</script>
</body>
</html>

You can load your images using ajax calls, and in case that the uses scrolls-out, you can abort the calls.
In jQuery pseudo-code it would be something like that (forgive me mistakes in syntax, it is just an example):
1) tag images that you want to load
$(".image").each( function(){
if ( is_in_visible_area(this) ) { // check [1] for example
$(this).addClass("load_me");
} else {
$(this).addClass("dont_load");
}
});
2) load images
ajax_requests = {};
$(".image.load_me").each( function(){
// load image
var a = $.ajax({
url: 'give_me_photos.php',
data: {img: photo_id},
success: function(html){
photo_by_id(photo_id), img.append(html);
}
});
ajax_requests[photo_id] = a;
});
3) cancel loading those out of the screen
for( id in ajax_requests ) {
if ( ! is_in_visible_area(id) ) {
ajax_requests[id].abort();
}
}
Of course, add also some checking if the image is already loaded (e.g. class "loaded")
[1]. Check if element is visible after scrolling
[2]. Abort Ajax requests using jQuery

BTW, another idea that might work:
1) create a new iframe
2) inside of the iframe have the script that starts loading the image, and once it's loaded, call the .parent's method
3) when in need, stop the iframe content loading using .stop on the iframe object

Use a stack to manage ajax requests (means you will have serial loading instead of parallel but it is worth it)
On scroll stop, wait for 300ms and then push all images inside view-area into stack
Every time a user scrolls check if a stack is running. (fyi - you can stop all requests to a particular url instead of killing all ajax calls. also you can use regex so it should not stop any other requests on the page)
If an existing stack is running - pop all the images that are in it except for the top most one.
On all ajax calls - bind beforeSend() event to remove that particular image from the stack
It is late right now, but we have done something very similar at work - if you need the detailed code let me know.
Cheers!

Maybe you could serve the image through a php script which would check a field in the the db (or better yet a memcached) that would indicate stop loading. the script would portion up the image into chunks and pause in between each chunk and check if the stop flag for the particular request is. If it is set you send the header with A 204 no content which as soon as the browser gets it will stop receiving.
This may be a bit over kill though.

The solution could be a webworker. a webworker can be terminated and with him the connection.
But there is a small problem that the webworker uses the limited connections of the browser so the application will be blocked.
Right now I'm working on a solution with serviceWorkers - they don't have a connection limit (I hope so)

delay images for display purposes not efficiency using javascript?

I have run into numerous sites that use a delay in loading images one after the other and am wondering how to do the same.
So i have a portfolio page with a number of images 3 rows of 4, what i want to happen is for the page to load,except for the images in img tags. Once the page has loaded i want images 1 of each row to load then say 0.5 seconds later the next image in the row(s) and so no. I'm going to have a loading gif in each image box prior to the actual image being displayed.
I know its doable but cant seem to find the term for doing this. This is purely for looks as it is a design site.
Thanks for the help.

This is very easy to do in jQuery
$('img').each(function(i) {
$(this).delay((i + 1) * 500).fadeIn();
});
Fiddle: http://jsfiddle.net/garreh/Svs7p/3
For fading in rows one after the other in a table it just means changing the selector slightly. Remember to change from div to img -- I just used div for testing
$('tr').each(function(i) {
$('td div', this).delay((i + 1) * 500).fadeIn();
});
Fiddle: http://jsfiddle.net/garreh/2Fg8S/

Here is what you can do, you can load the image tags with out the src and using a custom property:
<img alt='The image' path='image/path.jpg' />
then you can use javascript to load the images when the site is loaded or whenever you please;
// simplified
window.onload = function () {
var images = document.getElementsByTagName('img');
// loop and assign the correct
for (var i =0; i < images.length;i++){
var path = images[i].getAttribute('path');
images[i].src = path;
}
}
I hope you get the concept of how the images are delayed
**please note the path attribute is not a standard one.

The easiest way I can think to do this is to have a table set up that will eventually hold the image tags, but have none on load. Javascript can loop through an array of image urls, and insert those image tags into random locations on the table.
If you want to have the delay, setInterval is the perfect tool. http://www.w3schools.com/jsref/met_win_setinterval.asp
// You can hard-code your image url's here, or better still, write
// a server-side script that will read a directory and return them
// so it is fully dynamic and you can add images without changing code
unpickedImages = array();
// Start loading
loadAllImages = setInterval( insertImage, 600 );
function insertImage() {
if( unpickedImages.length > 0 ) {
var imageUrl = unpickedImages.shift();
// pick empty x, y on your table
// Insert the image tag im that <td></td>
} else {
clearInterval( loadAllImages );
}
}

You really don't need javascript to do this. If you specify the image sizes in the HTML or CSS, the browser will layout and display the page while loading the images, which will likely be loaded in parallel. It will then display them as soon as it can.
That way if users re-visit your site and have the images cached, they all show up immediately. If you have a script to load the images after a delay, you are making visitors wait for content unnecessarily and all their efforts to have a faster browser and pay for a fast internet connection has gone to waste.

I want to load a large HTML page with a lot of redundancy as fast as possible. What is the best way?

I want to load a very large HTML page containing nothing but the letter 'x' (let's say 10000 lines of each 100 characters), each of the characters linking to a similar url: the first one to www.example.com/1, the second to www.example.com/2, etc.
Of course I cannot just generate the entire page with php because it would build a very large file for the browser to download. But if I try it with javascript and a simple for-loop, it takes ages for the script to complete.
Any solutions for this problem?

Much better idea:
document.body.addEventListener("click", function (e) {
console.log("Clicked at coordinates ", e.pageX, e.pageY);
// Convert in your own fashion; here's one idea:
var index = (e.pageX % 100) + (100 * e.pageY);
window.location.href = "http://example.com/" + index;
});

Those are pretty much your only options. Only thing I think you can do is use a faster browser (test out the latest versions of the current browsers, recent years have seen lots of javascript optimization) and/or a faster computer.
The biggest issue though is why are you doing this? I can't think of any practical use for this, and most likely there's a better way to do what you're actually trying to accomplish
Even generating it server side, it'll likely take a long time to render. We've recently tried loading a page that hasn't needed paging previously because the dataset has always been small, but with a huge dataset even though the whole page was transferred, it still froze the entire browser for over 5 minutes before we had to kill the process. I suspect you'll run into similar issues if it's really that much stuff.

What you are trying to do is not very clever. 10,000 times 100 is 1,000,000 elements. The most efficient way is use P elements with a minimal id, then use a click listener on the body element to determine which element was clicked on and genrate the URL. So your html looks something like:
<html><title>Silly Page</title>
<style type="text/css">p {display:inline;margin:0;padding:0}</style>
<script type="text/javascript">
function doNav(e) {
var id = (e.target || e.srcElement).id;
window.location.href = 'http://www.example.com/' + id.replace('p','');
}
</script>
<body onclick="doNav(event)"><p id=p1>x<p id=p2>x<p id=p3>x<p id=p4>x...
</body>
If you are trying to associate a link with a location on a page, use an image map, it will be vastly more efficient.

You have two options:
To make a virtual view. In this case you
will load only visible elements and
do scrolling/panning manually
(similar to maps)
To output/populate just text
"xxxxx...." and handle clicks by
coordinates and synthesizing
hyperlink clicks by code. In this
case you will have only one DOM
element - container of x'es

The following chokes for about 20s in FF on my machine, about 6s in Chrome. A good portion of that is spent parsing the injected DOM, and I suspect this would remain the case for a downloaded DOM of the same structure. No matter how you approach this, it's going to foul up the user's browser for a while.
<script type="text/javascript">
//<![CDATA[
$(function() {
var strings=[];
for(var a=0;a<10000;a++)
{
for(var b=0;b<100;b++)
{
var c=a*100+b;
strings.push(
'x');
}
strings.push("<br/>");
}
var megaString=strings.join("");
$("body").html(megaString);
});
//]]>
</script>

Javascript/JQuery: Gallery with very large images. How can I have it on click fade out, load the next image, and then fade in w/ the new image?

my boss has me working on a website that basically has a very large gallery right in the middle.
The way this one part needs to work is that the user clicks a next/prev button, the image fades out, displays a loading spinning image gif, and then fades in with the new image when it's down downloading. I have no idea where to even begin.
I know jquery somewhat, but I'm very new to actual javascript. My only reference book at hand is a copy of "Javascript for Dummies" for 1997. Is this of any use to me at all, or has Javascript changed since then?

There are lots of jQuery plugin for image gallery: Galleria, GalleryView, Pikachoose, and this one.
Or you can search from jQuery plugins page.

Please get a newer book, or just use the web as a resource, any info. from 1997 is going to be horribly outdated.
This is a very simple site I've recommended to beginners before: http://htmldog.com/guides/javascript/
No, it doesn't cover everything, but that's what's good about it, you'll get some key things down, and then be able to search on google for more specific stuff.
To give you some barebones ot start with, I would do something like this:
$(document).ready(function() {
$('#nextBtn').click(function() {
transitionToNextImage ();
});
});
transitionToNextImage = function() {
$('img.active-image').fadeTo(1000,0), function() {
// fade out complete.
$('#inProgressGif').show();
getNextImage();
});
};
getNextImage = function() {
// make ajax call to get new image, and
// in the success callback of the ajax call,
// remove the inProgressGif, and
// add the image ot the DOM with opacity 0,
// then slowly fade it in to opacity 1 (opposite
// of what was done above
};