Displaying Hidden Javascript Divs if Java Enabled without Duplicate content - javascript

In short, I am trying to have an HREF menu with Javascript functions to display DIVs. However, my concern is that while I could have two seperate DIVs, one with Javascript if enabled, and one with No JAvascript enabled, I do not want to duplicate raw content on my page (as spiders will index Display: none html)
I am not familiar with functions of javascript, and best practices. My instinct is to string replace the DIVs for a specific id style tags when javascript is present..
Ie, logic that if javascript enabled, then replace text of style tags to to display=none (for specific ID's)
Also - is there a way to be nonspecific with javascript. Such as if i have contentid1,contentid2,contentid3,contentid4,contentid5,contentid6 I could use, via regular expression or equivalent for contentid 2-6
I will use this on multiple pages where contentids change. I do not know if i should create a javascript conditional style, as I am not sure how that style would be applied for multiple IDs (seen here)
Hide html only when Javascript is available
Heres my current code
<script type="text/javascript">
function showHide(d)
{
var onediv = document.getElementById(d);
var divs=['content1','content2','content3','content4'];
for (var i=0;i<divs.length;i++)
{
if (onediv != document.getElementById(divs[i]))
{
document.getElementById(divs[i]).style.display='none';
}
}
onediv.style.display = 'block';
}
</script>
then here is my menu
<ul>
<li>link1</li>
<li>link2</li>
<li>link3</li>
<li>link4</li>
</ul>
Then here is my content (note, i leave the content1 div visible by default
<div id="content1" >Content</div>
<div id="content2" style="display: none;">Stuff</div>
<div id="content3" style="display: none;">Things</div>`
I would like to avoid flickering if possible, and page refreshing if possible. Like could there be a condition so that content2+ have inlinestyle changed to hidden. If no javascript, my paeg just becomes really, really long.
?
Sorry-rambling. Tired, and have pneumonia :)

Related

Trying to build a content locker using jQuery

I am very new to jQuery and not entirely sure what I'm doing. Will try my best to explain the problem I'm facing.
I'm trying to lock some content on a landing page until a user shares the link using FB, Twitter, LinkedIN or G+. The first version of the script I wrote (which worked fine) ran like this:
<head>
<script type="text/javascript">
...
$(document).ready(function()
{
$('.class').click(clearroadblock());
buildroadblock();
}
</script>
<style>
.class
{
[css stuff]
}
</style>
</head>
<body>
<div id="something">
<ul>
<li> Link1 </li>
<li> Link2 </li>
</ul>
</div>
</body>
The problem I'm now facing is changing out this code to replace the list elements with social share buttons. As they are no longer under .class, but classes like fb-share-button and twitter-share-button. Please help me understand what I need to modify to accommodate this? PS: This is not a Wordpress site.
function clearroadblock()
{
$('#roadblockdiv').css('display', 'none');
$('#roadblockBkg').css('display','none');
}
This is the way I'm clearing the overlay once a click is detected, BTW.
Can I wrap the social buttons in divs, assign them IDs and use those IDs to trigger the click like below?
<div id="Button">
Tweet
</div>
$('#Button').click(clearroadblock());
You can have multiple classes on an element by separating them with a space. Try the following:
class="class fb-share-button"
Your jquery will still work off the "class" class. I would recommend you change this name to something more meaningful though. Your css can target the "class" for general styles, but you can also target fb and twitter separately.
Update
I decided to create a quick JSFiddle for this.
Some of the styles etc won't be the same as what you're doing, but the problem is resolved. I've created a div with id main that contains the content that you want to hide. There's an absolutely positioned div over the top of this, this is the roadblock. The javascript is showing the roadblock (assuming that's what you wanted to do with buildroadblock()).
On click of a link in the ul with id socialMedia we call clearroadblock. Notice the lack of parenthesis. This hides the roadblock.
This isn't a great way of preventing someone from seeing information, you might want to think about pulling the content down from the server when the action is performed, however, I think this answers your question.

Replacing text on web page using HTML or Javascript

I am customizing an HTML page provided and hosted by a third-party, so I am severely restricted in what I can do to the page. On the page there is a navigation menu that looks like this.
<ul class='nav'>
<li class='active'>
<a href='/affiliate'>
<span id='affiliate-nav-homepage'>
<span class='default'>Home Page</span>
</span>
</a>
</li>
<li>...
Question: How can I make the above snippet display the text "Home" instead of "Home Page", if all I am allowed to do is add a <style> element in the page <head>; and add some HTML code (which may include Javascript) near the start of the page?
I have a considered going down one of these two paths, but both paths are problematic.
1) Use CSS to hide their text ("Home Page"). Add my own text ("Home") using :before or :after pseudo-selectors.
display: none is probably not a good way to hide the text, because browsers that don't understand :before and :after will still understand display: none and I will end up with no text at all.
Are there better CSS alternatives for me? Change font size to 0? change text color? Manipulate z-index somehow? It is OK if some older browsers display the text "Home Page". It is not OK if some browsers display "Home Page Home", or if some browser do not display any text at all.
-- OR --
2) Use Javascript to manipulate the DOM
The difficulty with Javascript is that I can only insert it near the start of the page body before the elements that I want to modify. I could hook an event that fires after the entire page is loaded, but I want to avoid the page text flashing (the text "Home Page" being displayed briefly and then changing to "Home"). Is there such an event and how would I hook it?
Thank you for you help.
Anti flashing fix:
.default { display: none; }
Changing text and showing, when document is ready:
body.onload = function (){
//getElementsByClassName not working in old browsers, so ...
var el = document.getElementById('affiliate-nav-homepage').getElementsByTagName('span')[0];
el.innerHTML = 'Home';
el.style.display = 'block';
};
Additional You can hide all content and show it after all javascript changes by this method.
This is not elegant solution, but as You say, You have limited options to resolve Your problem.
In JavaScript
window.addEventListener("load", function(){
document.querySelector("span.default").textContent = "Home";
//using document.querySelector to select the span with classname default
//using textContent to change the content of the node.
}, false);
In a script block will do it.
This will execute on page load. This will be executed so fast that in almost all cases you won't see text jumping.
Example:
window.addEventListener("load", function(){
document.querySelector("span.default").textContent = "Home";
}, false);
<ul class='nav'>
<li class='active'>
<a href='/affiliate'>
<span id='affiliate-nav-homepage'>
<span class='default'>Home Page</span>
</span>
</a>
</li>
</ul>
When your page loading becomes slowed by other resources, #Mateusz Mania's idea of using CSS to hide the element and bring it up again is actually pretty nice. I would suggest using opacity: 0 or visibility: hidden instead of display:none since the latter will remove the element from the page and when it becomes visible again it will make the content jump down below it.
Exploring the CSS option
#affiliate-nav-homepage:before{
content: "Home";
}
.default {
display: none;
}
<ul class='nav'>
<li class='active'>
<a href='/affiliate'>
<span id='affiliate-nav-homepage'>
<span class='default'>Home Page</span>
</span>
</a>
</li>
</ul>

Formatting dynamically formed HTML elements created after Script is run

So this is actually a very tricky concept to portray so here is my attempt.
I am utilizing an HTML form template in LANDesk Service Desk - tool is irrelevant but important to note that there is back-end code that I cannot touch that is generating HTML.
So basically, the tool is pulling data from a back-end database containing a list of objects. It then inputs this data into an HTML form template that I have created using variables as placeholders for the objects. The HTML is then built on the fly with however many objects are in the database. Thus, I have no way of accessing the head - (which means native JS, and inline CSS).
My template looks like this...
<div class="my-template">
<a class="my-template my-link">My Link</a>
</div>
<script>
var myLinks = document.getElementsByClassName('my-link');
for (var i = 0 ; i < myLinks.length ; i++) {
myLinks[i].style.display = "none";
}
</script>
When I view the source on the loaded page it looks something like this...
<body>
<!--misc. page stuff-->
<!--First Item-->
<div class="auto-create">
<div class="my-template">
<a class="my-template my-link">My-Link</a>
</div>
</div>
<!--Second Item-->
<div class="auto-create">
<div class="my-template">
<a class="my-template my-link">My-Link</a>
</div>
</div>
</body>
All of the elements are formatted the way I want them to be...besides the last element on each page. I have determined that this is because each time the tool is running the object through the template, it is running the script. The issue is, there is a stupid default button that they place at the bottom of each object that is broken. (This is why I have the script changing the style to display: none..should have mentioned this earlier). Basically I want to delay the execution of the script until not only the object has been run through the template...but the entire page has loaded...but I can't seem to get the last button to go away.
I know that this is a lot of poorly written words trying to form an explanation, but I really think this is impossible...but I am convinced there has to be a way. (Also, the company isn't providing us with any help in finding a workaround, so I had to basically MacGyver this one

Updating the content of a div with javascript

Rather than trying to create tons of different pages on my website, I'm trying to update the content of a single div when different items in the navbar are click to update the maint div content. I tried to find a simple example using Javascript:
<script type="text/javascript">
function ReplaceContentInContainer(id,content) {
var container = document.getElementById(id);
container.innerHTML = content;
}
</script>
<div id="example1div" style="border-style:solid; padding:10px; text-align:center;">
I will be replaced when you click.
</div>
<a href="javascript:ReplaceContentInContainer('example1div', '<img src='2.jpg'>' )">
Click me to replace the content in the container.
</a>
This works just fine when I only try and update text, but when I put an img tag in there, as you can see, it stops working.
Either
1) what is the problem with how I am trying to do it?
or 2) What is a better/easier way to do it?
I'm not stuck on Javascript. jQuery would work too, as long as it is just as simple or easy. I want to create a function that will just let me pass in whatever HTML I want to update and insert it into the div tag and take out the 'old' HTML.
You just have some escaping issues:
ReplaceContentInContainer('example1div', '<img src='2.jpg'>')
^ ^
The inner ' need to be escaped, otherwise the JS engine will see ReplaceContentInContainer('example1div', '<img src=' plus some syntax errors resulting from the subsequent 2.jpg'>'). Change the call to (tip of the hat to cHao' answer concerning escaping the < and > in the HTML):
ReplaceContentInContainer('example1div', '<img src=\'2.jpg\'>')
A simple way to do this with jQuery would be to add an ID to your link (say, "idOfA"), then use the html() function (this is more cross-platform than using innerHTML):
<script type="text/javascript">
$('#idOfA').click(function() {
$('#example1div').html('<img src="2.jpg">');
});
</script>
First of all, don't put complex JavaScript code in href attributes. It's hard to read or to maintain. Use the <script> tag or put your JavaScript code in a separate file altogether.
Second, use jQuery. JavaScript is a strange beast: the principles underlying its patterns were not designed with modern-day web development in mind. jQuery gives you lots of power without miring you in JavaScript's oddities.
Third, if your goal is to avoid having to endlessly duplicate the same basic structure for all (or many) of your pages, consider using a templating system. Templating systems allow you to plug in specific content into scaffolds containing the common elements of your site. If it sounds complicated, it's because I haven't explained it well. Google it and you'll find lots of great resources.
Relying on JavaScript for navigation means your site won't be indexed properly by search engines and will be completely unusable to someone with JavaScript turned off. It is increasingly common--and acceptable--to rely on JavaScript for basic functionality. But your site should, at minimum, provide discrete pages with sensible and durable URLs.
Now, all that said, let's get to your question. Here's one way of implementing it in jQuery. It's not the snazziest, tightest implementation, but I tried to make something very readable:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>jQuery Example</title>
<style type="text/css" media="all">
/* all content divs should be hidden initially */
.content {
display: none;
}
/* make the navigation bar stand out a little */
#nav {
background: yellow;
padding: 10px;
}
</style>
</head>
<body>
<!-- navigation bar -->
<span id="nav">
about me |
copyright notice |
a story
</span>
<!-- content divs -->
<div class="content" id="about_me">
<p>I'm a <strong>web developer</strong>!</p>
</div>
<div class="content" id="copyright">
<p>This site is in the public domain.</p>
<p>You can do whatever you want with it!</p>
</div>
<div class="content" id="my_story">
<p>Once upon a time...</p>
</div>
<!-- jquery code -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js"></script>
<script>
// Wait for the document to load
$(document).ready(function() {
// When one of our nav links is clicked on,
$('#nav a').click(function(e) {
div_to_activate = $(this).attr('href'); // Store its target
$('.content:visible').hide(); // Hide any visible div with the class "content"
$(div_to_activate).show(); // Show the target div
});
});
</script>
</body>
</html>
Ok, hope this helps! If jQuery looks attractive, consider starting with this tutorial.
Your main problem with your example (besides that innerHTML is not always supported) is that < and > can easily break HTML if they're not escaped. Use < and > instead. (Don't worry, they'll be decoded before the JS sees them.) You can use the same trick with quotes (use " instead of " to get around quote issues).

Better alternative to an iframe to display tab content?

I have a page with an iframe to feature the contents of the clicked tab. There are 3 tabs and 1 iframe. The sources of the contents relating to each tab clicked are formatted and coded in other html & css files.
What is another alternative to using an iframe, because I noticed that when the tab is clicked, it still shows the white background, similar to when a new page is loading?
Here's my code:
<div id="tabs">
<div id="overview">
<a target="tabsa" class="imagelink lookA" href="toframe.html">Overviews</a>
</div>
<div id="gallery">
<a target="tabsa" class="imagelink lookA" href="tawagpinoygallery.html">Gallery</a>
</div>
<div id="reviews">
<a target="tabsa" class="imagelink lookA" href="trframe.html">Reviews</a>
</div>
</div>
<div id="tabs-1">
<iframe src="toframe.html" name= "tabsa" width="95%" height="100%" frameborder="0">
</iframe>
</div>
The only alternative to using IFRAMEs to load dynamic content (after the page has loaded) is using AJAX to update a container on your web page. It's pretty elegant and usually faster than loading a full page structure into an IFRAME.
Ajax with JQuery (use this and you will be loved on SO; the AJAX functions are great and simple)
Ajax with Prototype
Ajax with MooTools
Standalone Ajax with Matt Kruse's AJAX toolbox (Used to use this, using JQuery today because I needed a framework)
AJAX with Dojo (Said to be fast, but AJAX is not as straightforward)
Another alternative is to use AJAX to load the content of a tab and use a div to display the content. I would suggest that using an existing Tab library might be an option rather than trying to solve all the problems associated with creating tabs.
Maybe the jQuery UI Tab might be helpful here if you like to try it.
EDIT: AJAX example with UI Tabs.
First, the HTML will look like this.
<div id="tabs">
<ul>
<li><span>Overviews</span></li>
<li><span>Gallery</span></li>
<li><span>Reviews</span></li>
</ul>
</div>
Then make sure that you import the appropriate jQuery files:
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/themes/ui-lightness/jquery-ui.css" type="text/css" media="all" />
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js" type="text/javascript"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js" type="text/javascript"></script>
etc...
Then add the code to create the tabs:
<script type="text/javascript">
$(function() {
$("#tabs").tabs();
});
</script>
There's an alternative to AJAX!
You can load ALL three possible contents into separate DIVs.
Then clicking on a tab will simply make the display attribute of the appropriate content's DIV "block" while making the other two DIVs' display property "none".
Cheap, easy, does not require AJAX costs for extra http request or for coding.
Mind you, AJAX is a better solution if the contents of the tabs will change dynamically based on other data as opposed to being known at the time the page loads.
You don't need script.
<ul><li>foo link<li>bar link</ul>
<div class="tab" id="foo">foo contents</div>
<div class="tab" id="bar">bar contents</div>
Plus this CSS, in most browsers: .tab:not(:target) { display: none !important; }, which defaults to all content visible if :target isn't supported (any modern browser supports it).
If you're showing content with script, always hide it with script. Let it degrade gracefully if that script doesn't run.
It's probably better to load in the content for each tab into DIVs on the same page and then switch the visibility of each DIV when a tab button is clicked using JavaScript and the CSS display property.
If you can't do that then iframe is probably the best solution. You can make the iframe background transparent, see below:
<iframe src="toframe.html" name= "tabsa" width="95%" height="100%" frameborder="0" allowtransparency="true"></iframe>
You would then need to add the following CSS to the BODY element using:
BODY { Background: transparent; }
The HTML iframe is to be used to include/display non-template content, such as a PDF file. It's considered bad practice when used for template content (i.e. HTML), in both the SEO and UX opinions.
In your case you just want to have a tabbed panel. This can be solved in several ways:
Have a bunch of links as tabs and a bunch of div's as tab contents. Initially only show the first tab content and hide all others using CSS display: none;. Use JavaScript to toggle between tabs by setting CSS display: block; (show) and display: none; (hide) on the tab content divs accordingly.
Have a bunch of links as tabs and one div as tab contents. Use Ajax to get the tab content asynchronously and use JavaScript to replace the current tab contents with the new content.
Have a bunch of links as tabs and one div as tab contents. Let each link send a different GET request parameter or pathinfo representing the clicked tab. Use server-side flow-control (PHP's if(), or JSP's <c:if>, etc) or include capabilities (PHP's include(), or JSP's <jsp:include>, etc) to include the desired tab content depending on the parameter/pathinfo.
When going for the JavaScript based approach, I can warmly recommend to adopt jQuery for this.
This is jQuery example that includes another html page into your document. This is much more SEO friendly than iframe. In order to be sure that the bots are not indexing the included page just add it to disallow in robots.txt
<html>
<header>
<script src="/js/jquery.js" type="text/javascript">
</header>
<body>
<div id='include-from-outside'></div>
<script type='text/javascript'>
$('#include-from-outside').load('http://example.com/included.html');
</script>
</body>
</html>
You could also include jQuery directly from Google: http://code.google.com/apis/ajaxlibs/documentation/ - this means optional auto-inclusion of newer versions and some significant speed increase. Also, means that you have to trust them for delivering you just the jQuery ;)
As mentioned, you could use jQuery or another library to retrieve the contents of the HTML file and populate it into the div. Then you could even do a fancy fade to make it look all pretty.
http://docs.jquery.com/Ajax/jQuery.get
Something along these lines:
$.get("toframe.html", function(data){
$("#tabs-1").html(data);
});
edit..
you could prepopulate or onclick you could do the get dynamically
$("#tabs a").click(function(){
var pagetoget = $(this).attr("href");
$.get...
})
If you prepopulate could have three containers instead of the one you have now, 2 hidden, 1 display, and the click functions will hide them all except for the one you want.
The get is less code though, easier time.

Categories

Resources