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shadowbox stops working after jquery function call

I have a shadowbox script. When I load the page everything works fine, but when I call this jquery load function and then try to trigger the shadowbox by clicking on the image, the large image opens in new window instead. Here's the code:

<link href="CSS/main.css" rel="stylesheet" type="text/css" />
<script type="text/javascript"  src="shadowbox-3.0.3/shadowbox.js"></script>
<script type="text/javascript">
Shadowbox.init();
</script>

<p id="compas"><a href="images/coverage.jpg" rel="shadowbox" title="Coverage map"></a></p>

Any idea why this is happening?

like image 289
Igor Avatar asked Feb 04 '12 21:02

Igor


1 Answers

EDIT

So, we finally get the bottom of this. 15 hours after first commenting on this issue, and at least 50 iterations later, we finally have identified what the problem is and how to fix it.

It actually struck me suddenly when I was creating local aaa.html and bbb.html on my server. That was when it hit me that the element nodes for the content that was being replaced was being removed altogether from the DOM when $.load() runs the callback function. So, once the #menu-home content elements were replaced, they were removed from the DOM and no longer had Shadowbox applied to them.

Once I figured this out, it was just a matter of a single web search and I found:

Nabble-Shadowbox - Reinit Shadowbox

Specifically, the response from mjijackson. What he describes is how to "restart" (reinitialize) Shadowbox using:

Shadowbox.clearCache();
Shadowbox.setup();

So once the #menu-home content was reloaded, what needs to happen is the Shadowbox cache needs to be cleared (essentially, shutting it down on the page), then the Shadowbox.setup() is run, which will detect the elements all over again. You don't run the Shadowbox.init() method again either.

I noticed that you had tried to copy/paste the Shadowbox.setup() in after the $.load(), at least sequentially in the code. However, this wasn't going to work, due to the cache clearing that needs to happen first, and primarily because the .clearCache() and .setup() functions need to be run after the $.load() completes (finishes and runs any callbacks). Those two functions need to be run in the $.load() callback handler; otherwise, you're running it's immediately, but the $.load() is asynchronous and will complete at some later time.

I'm going to go over some other changes I made, just so you understand what, why and wherefore.

Note, I'm not sure if you're familiar with <base>, but the following is at the top of the HEAD element:

<base href="http://62.162.170.125/"/>

This just let's me use the resource files on your computer. You'll not want to use this on your actual site more than likely. If you copy/paste, make sure and remove this line.

<div id="menu">
  <ul>
    <li><a id="menu-home" href="index.html" rel="http://jfcoder.com/test/homecontent.html">Home</a></li>
    <li><a id="menu-services" href="services.html" rel="http://jfcoder.com/test/servicescontent.html">Services</a></li>
    <li><a id="menu-tour" href="tour.html" rel="http://jfcoder.com/test/tourcontent.html">Tour</a></li>
    <li><a id="menulogin" href="login.html">Login</a></li>
  </ul>
</div>

Here, you'll notice I have a relative url in the HREF attribute, and a link to some pages on my server. The reason for the links to my server is that I couldn't access your aaa.html and bbb.html files through AJAX due to cross-site scripting limitations. The links to my website should be removed as well.

Now, the reason I'm using the rel attribute here is that I want allow for the links by way of the href attribute to continue to work in case the JS doesn't function correctly or there's some other error. If you have separate files, one for full HTML document and another for just the fragments, this is what you'll want to do. If you can serve both the full document AND the content-only from the linked file, then you probably don't need the rel attribute, but you'll need to manage the request so the server knows how to respond (full document or just the content part).

var boxInitialize = function(){
    try {
        if (!Shadowbox.initialized) {
            Shadowbox.init();
            Shadowbox.initialized = true;
        } else {
            Shadowbox.clearCache();
            Shadowbox.setup();
        }
    } catch(e) {
        try {
            Shadowbox.init();
        } catch(e) {};
    }
};

All I've done here is create a central location for the initialization/setup requests. Fairly straightforward. Note, I added the Shadowbox.initialized property so I could keep track of if the Shadowbox.init() had run, which can only be run once. However, keeping it all in one spot is a good idea if possible.

I also created a variable function which can be called either as a regular function:

boxInitialize();

Or as a function reference:

window.onload = boxInitialize; // Note, no () at the end, which execute the function

You'll probably notice I removed the $() and replaced them with jQuery() instead. This can turn into a real nightmare if you end up with an environment with multiple frameworks and libraries competing for $(), so it's best to avoid it. This actually just bit me real good the other day.

Since we have a closure scope within the .ready() callback, we can take advantage of that to save several "private" variables for ow use at different times in the scripts execution.

var $ = jQuery,
    $content = jQuery("#content"), // This is "caching" the jQuery selected result
    view = '',
    detectcachedview = '',
    $fragment,
    s = Object.prototype.toString,
    init;

Note the , at the end of all but the last line. See how I "imported" the $ by making it equal to the jQuery variable, which means you could actually use it in that#.

var loadCallback = function(response, status, xhr){
    if (init != '' && s.call(init) == '[object Function]') {
        boxInitialize();
    }

    if (xhr.success() 
          && view != '' 
            && typeof view == 'string' 
              && view.length > 1) {
        $fragment = $content.clone(true, true);
        cacheContent(view, $fragment);
    }
};

This runs when the $.load() completes the process of the AJAX request. Note, the content returned in the request has already been placed on the DOM by the time this runs. Note as well that we're storing the actual cached content in the $content.data(), which should never be removed from the page; only the content underneath it.

var cacheContent = function(key, $data){
    if (typeof key == 'string'
          && key.length > 1
            && $data instanceof jQuery) {
        $content.data(key, $data.html());
        $content.data(detectcachedview, true);
    }
};

cacheContent() is one a method you may not want; essentially, if it was already loaded on a previous request, then it will be cached and then directly retrieved instead of initiating another $.load() to get the content from the server. You may not want to do this; if so, just comment out the second if block in the menuLoadContent() function.

var setContent = function(html){
    $content.empty().html(html);

    if (init != '' && s.call(init) == '[object Function]') {
        boxInitialize();
    }
};

What this does is first empty the $content element of it's contents/elements, then add the specified string-based markup that we saved earlier by getting the $content.html(). This is what we'll re-add when possible; you can see once the different links have been clicked and loaded, reclicking to get that to redisplay is really quick. Also, if it's the same request as currently loaded, it also will skip running the code altogether.

(We use $content like because it is a reference to a variable containing a jQuery element. I am doing this because it's in a closure-scope, which means it doesn't show up in the global scope, but will be available for things like event handlers.

Look for the inline comments in the code.

var menuLoadContent = function(){
    // This is where I cancel the request; we're going to show the same thing
    // again, so why not just cancel?
    if (view == this.id || !this.rel) {
        return false;
    }

    // I use this in setContent() and loadCallback() functions to detect if
    // the Shadowbox needs to be cleared and re-setup. This and code below
    // resolve the issue you were having with the compass functionality.
    init = this.id == 'menu-home' ? boxInitialize : '';
    view = this.id;
    detectcachedview = "__" + view;

    // This is what blocks the superfluous $.load() calls for content that's
    // already been cached.
    if ($content.data(detectcachedview) === true) {
        setContent($content.data(view));
        return false;
    }

    // Now I have this in two different spots; there's also one up in 
    // loadCallback(). Why? Because I want to cache the content that
    // loaded on the initial page view, so if you try to go back to
    // it, you'll just pickup what was sent with the full document.
    // Also note I'm cloning $content, and then get it's .html() 
    // in cacheContent().
    $fragment = $content.clone(true, true);
    cacheContent(view, $fragment);

    // See how I use the loadCallback as a function reference, and omit
    // the () so it's not called immediately?
    $content.load(this.rel, loadCallback);

    // These return false's in this function block the link from navigating
    // to it's href URL.
    return false;
};

Now, I select the relevant menu items differently. You don't need a separate $.click() declaration for each element; instead, I select the #menu a[rel], which will get each a element in the menu that has a rel="not empty rel attribute". Again, note how I use menuLoadContent here as a function reference.

jQuery("#menu a[rel]").click(menuLoadContent);

Then, at the very bottom, I run the boxInitialize(); to setup Shadowbox.

Let me know if you have any questions.


I think I might be getting to the bottom of this. I think the flaw is the way you're handling the $.load() of the new content when clicking a menu item, coupled with an uncaught exception I saw having to do with an iframe:

Uncaught exception: Unknown player iframe

This Nabble-Shadowbox forum thread deals with this error. I'm actually not getting that anymore, however I think it came up with I clicked on the tour menu item.

Now, what you're doing to load the content for the menu items really doesn't make any sense. You're requesting an entire HTML document, and then selecting just an element with a class="content". The only benefit I can see for doing this is that the page never reloads, but you need to take another approach to how to get and display the data that doesn't involve downloading the entire page through AJAX and then trying to get jQuery to parse out just the part you want.

I believe handling the content loading this way is the root cause of your problem, hence the $.load() toggling of menu views breaks your page in unexpected ways.

Question: Why don't you just link to the actual page and skip all the $.load() fanciness? Speed-wise, it won't make that much of an impact, if any at all. It just doesn't make sense to use AJAX like this, when you could just link them to the same content without issue.

There are two alternatives that would allow you to prevent roundtrip page reloads:

  1. Setup your AJAX calls to only request the .content portion of the markup if you have the ?contentonly=true flag in the URL, not the entire HTML document. This is how it's traditionally done, and is usually relative simple to do if you have a scripting environment.

    $(".content").load('index.html?contentonly=true');
    

    Then your server responds only with the content view requested.

  2. Serve all of the content views within the same HTML document, then show as appropriate:

    var $content = $('.content');
    $content.find('.content-view').hide();
    $content.find('#services-content').show();
    

    It doesn't look like you have a whole lot of content to provide, so the initial page load probably won't have that much of an impact with this particular approach. You might have to look into how to preload images, but that's a very well known technique with many quality scripts and tutorials out there.

Either one of these techniques could use the #! (hashbang) technique to load content, although I believe there are some issues with this for search engines. However, here is a link to a simple technique I put together some time ago:

http://jfcoder.com/test/hash.html

Also, this is just a tip, but don't refer to your "content" element with a class, ie, .content. There should only be one content-displaying element in the markup, right? There's not more than one? Use an id="content"; that's what ID attributes are for, to reference a single element. classes are meant to group elements by some characteristic they share, so above when I .hide() the inline content views (see #2), I look for all of the class="content-view" elements, which are all similar (they contain content view markup). But the $content variable should refer to $('#content');. This is descriptive of what the elements are.

like image 84
Jared Farrish Avatar answered Nov 15 '22 20:11

Jared Farrish