The code below works fine with ONE Reveal/Hide Text process
<div class="reveal">Click Here to READ MORE...</div>
<div style="display:none;">
<div class="collapse" style="display:none;">Collapse Text</div>
However if this code is duplicated multiple times, the Collapse Text shows up and doesn't disappear and in fact conflicts with the Expand to reveal even more text instead of collapsing as it should.
In this http://jsfiddle.net/syEM3/4/ click on any of the Click Here to READ MORE...
Notice how the Collapse Text shows up at the bottom of the paragraphs and doesn't disappear. Click on the Collapse and it reveal more text.
How do I prevent this and getting to work as it should?
The two slideDown function calls are not specific to the .reveal and/or .collapse that you are currently doing. i.e.
$(".collapse").slideDown(100);
will find all the elements with the class .collapse on the page, and slide them down. irrespective of what element you just clicked.
I would change the slideDown call to be relavant to the element you just clicked i.e. something like this
$('.reveal').click(function() {
$(this).slideUp(100);
$(this).next().slideToggle();
$(this).next().next(".collapse").slideToggle(100);
});
in your code
$('.reveal').click(function() {
$(this).slideUp(100);
$(this).next().slideToggle();
$(".collapse").slideDown(100);
});
$('.collapse').click(function() {
$(this).slideUp(100);
$(this).prev().slideToggle();
$(".reveal").slideDown(100);
});
this two rows doesn’t do what you want as they act on all elements of the specified class
$(".reveal").slideDown(100);
$(".collapse").slideDown(100);
When you do $(".collapse").slideDown(100);, jQuery runs slideDown on everything with the .collapse class, not just the one that's related to your current this. To fix this, refer to the collapse based on its location to $(this).
Do do this, use something like $(this).siblings(".collapse").slideDown(100);
Note that this particular selector will only work if you enclose each text block in its own div. With each text element in its own div, like you have it now, .siblings(".collapse"), which selects all the siblings of $(this) with the collapse class, will still select both of the collapse elements.
Okay, I think you should take a different approach to your problem.
See, jQuery basically has two purposes:
Selecting one or more DOM elements from your HTML page
manipulate the selected elements in some way
This can be repeated multiple times, since jQuery functions are chainable (this means you can call function after function after function...).
If I understood your problem correctly, you are trying to build a list of blog posts and only display teasers of them.
After the user clicks the "read more" button, the complete article gets expanded.
Keep in mind: jQuery selects your elements very much like CSS would do. This makes it extremely easy to
come up with a query for certain elements, but you need to structure your HTML in a good way, like
you would do for formatting reasons.
So I suggest you should use this basic markup for each of your articles (heads up, HTML5 at work!):
<article class="article">
<section class="teaser">
Hey, I am a incredible teaser text! I just introduce you to the article.
</section>
<section class="full">
I am the articles body text. You should not see me initially.
</section>
</article>
You can replace the article and section elements with div elements if you like to.
And here is the CSS for this markup:
/* In case you want to display multiple articles underneath, separate them a bit */
.article{
margin-bottom: 50px;
}
/* we want the teaser to stand out a bit, so we format it bold */
.teaser{
font-weight: bold;
}
/* The article body should be a bit separated from the teaser */
.full{
padding-top: 10px;
}
/* This class is used to hide elements */
.hidden{
display: none;
}
The way we created the markup and CSS allows us to put multiple articles underneath.
Okay, you may have noticed: I completely omitted any "read more" or "collapse" buttons. This is done by intention.
If somebody visits the blog site with javascript disabled (maybe a search engine, or a old mobile which doesn't support JS or whatever),
the logic would be broken. Also, many text-snippets like "read more" and "collapse" are not relevant if they don't actually do anything and are not part of the article.
Initially, no article body is hidden, since we didn't apply the hidden css class anywhere. If we would
have embedded it in the HTML and someone really has no JavaScript, he would be unable to read anything.
Adding some jQuery magic
At the bottom of the page, we are embedding the jQuery library from the google CDN.
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
This is a best practice and will normally speed up your page loading time. Since MANY websites are embedding
jQuery through this URL, chances are high that its already in the visitors browser cache and doesn't have
to be downloaded another time.
Notice that the http: at the beginning of the URL is omitted. This causes browsers to use the pages current protocol,
may it be http or https. If you would try and embed the jQuery lib via http protocol on a https website, some browsers will refuse to download the file from a unsecure connection.
After you included jQuery into the page, we are going to add our logic into a script tag. Normally we would
save the logic into a separate file (again caching and what not all), but this time a script block will do fine.
Finally some JavaScript
At first, we want to hide all elements with the css-class full, since only teasers should remain displayed. This is very easy with jQuery:
$('.full').hide();
The beginning of the script $('.full') tells jQuery: I need all elements with the CSS-class full. Then we call a function on that result, namingly hide() which purpose should be clear.
Okay, in the next step, we want to add some "read more" buttons, next to every teaser. Thats an easy task, too:
$('.teaser').after('<button class="more">Read more</button>');
We now select every element with the css-class teaser and append some HTML code after() each element - a button with the css-class more.
In the next step, we tell jQuery to observe clicks on every one of this freshly created buttons. When a user has clicked, we want to expand the next element with the css-class full after the clicked button.
$('.more').on('click', function(){
//"this" is a reference to the button element!
$(this).slideUp().next('.full').slideDown();
});
Phew, what did we do here?
First, we told jQuery that we wanted to manipulate this, which is a reference to the clicked button. Then we told
jQuery to hide that button (since its not needed anymore) slowly with slideUp().
We immediately continued telling jQuery what to do: Now take the next() element (with the css-class full) and make it visible by sliding it down with slideDown().
Thats the power of jQuerys chaining!
Hiding again
But wait, you wanted to be able to collapse the articles again! So we need a "collapse" button, too and
some more JavaScript:
$('.full').append('<button class="collapse">Collapse text</button>');
Note: we didn't use the after() function to add this button, but the append() function to place the button
INSIDE every element with the css-class full, rather than next to it. This is because we want the
collapse buttons to be hidden with the full texts, too.
Now we need to have some action when the user clicks one of those buttons, too:
$('.collapse').on('click', function(){
$(this).parent().slideUp().prev('.more').slideDown();
});
Now, this was easy: We start with the button element, move the focus to its parent() (which is the element that contains the full text) and tell jQuery to hide that element by sliding it up with slideUp().
Then we move the focus from the full-text container to its previous element with the css-class more, which is its expanding button that has been hidden when expanding the text. We slowly show that button again by calling slideDown().
Thats it :)
I've uploaded my example on jsBin.
Related
So my website is built using a company's software called Inksoft which leaves me very little to work in the way of customization. So I have to do many workarounds.
Here is my site's homepage.
The header on top of the page only has two links right now. "Products" and "Design Studio". My goal is to add an "About Us" link and "Buyers Guide" to the header as well.
I cannot add new content to the header using Inksoft's backend. So I coded a workaround to replace the content of existing DIV's within the header to say and link to where I want them to go.
The only issue is, the responsive mobile-nav loses functionality when this is implemented. As seen here on this test page.
The test page has the About Us in the top header, added by the use of this code:
<script>
$("#header-nav-designs").html('<document.write="<li id="header-nav-studio"><font color="#000000">About Us</font></li>');
</script>
So, the simplified question is: how do I implement this code without losing the responsive functionality of the nav bar?
The jQuery .html function will replace the HTML inside the target element. If you want to just append the one value, you likely want to .append to the element.
In addition, you aren't setting the HTML to a valid html string. You probably just want to get rid of the <document.write=" at the beginning of the string. The rest of it looks fine with just a cursory glance.
So:
<script>
$("#header-nav-designs").append('<li id="header-nav-studio"><font color="#000000">About Us</font></li>');
</script>
Edit:
After looking at it a little more, it appears as though the $('#header-nav-designs') that you are selecting is already an <li> which means you need to either select the parent <ul> list or you can use the jquery .after function instead.
<script>
$("#header-nav-designs").after('<li id="header-nav-studio"><font color="#000000">About Us</font></li>');
</script>
And as someone else commented above, you are getting an error on the page. It appears as though you are trying to get an element with the id divID and the appending some html to it, but there is no element with the id divID and so you are getting an error saying that you can't read the property innerHTML of null as the call to document.getElementById is returning null (element not found).
Element id header-nav-designs witch your code is referring have CSS style on line 170:
#header-nav-designs {display:none;}
The element will be hidden, and the page will be displayed as if the element is not there. With display:none;
If I understand you correctly your code selector points to wrong element id. It should point $(".header-nav > ul"). Document.write is not needed inside jQuery you need to give only an valid html string as argument.
jQuery html function erase html that is all ready inside element and replace it with html string given as argument. You have to use append if you want to add more html but not remove what is allready in element.
$(".header-nav > ul").append('<li><font color="#000000">About Us</font></li>');
$(".header-nav > ul").append('<li><font color="#000000">Buyers Guide</font></li>');
I was hoping someone could help me out with this simple question: I’ve just started to learn jQuery and found a code to show hidden text after selecting an item.
I’d like to update it so that:
a.) The selected item is bold
b.) I can add placeholder text instead of starting off with a blank hidden text field
I foolishly assumed I could solve a.) by using the :active property in css, but that only works as long as the link is clicked on. (As soon as you release the mouse button it’s gone.) Just like b.), this is probably only possible by using jQuery as well? If so, would be really great if you could show me how to solve it. :)
The codes: http://jsfiddle.net/KUtY5/1/
JS
$(document).ready(function(){
$("#nav a").click(function(){
var id = $(this).attr('id');
id = id.split('_');
$("#menu_container div").hide();
$("#menu_container #menu_"+id[1]).show();
});
});
CSS
#menu_container {
width: 650px;
height: auto;
padding-left: 30px;
}
#menu_container div {
display:none;
}
HTML
<div id='nav'>
<a id="show_apps">Appetizers</a> | <a id="show_soups">Soups and Salads</a> | <a id="show_entrees">Entrees</a>
</div>
<div id="menu_container">
<div id="menu_apps">
Content of the App Section Here
</div>
<div id="menu_soups">
Content of the Soups Section Here
</div>
<div id="menu_entrees">
Content of the Entrees Section Here
</div>
</div>
Updated fiddle
You can realize a) using a custom class bold for example and the following code :
CSS
.bold{ font-weight: bold;}
JS
$(this).addClass('bold').siblings('a').removeClass('bold');
For b) I can't find any textfield in your code.
Hope this helps.
I have added some extra lines to your code and you can check it from here http://jsfiddle.net/KUtY5/483/.
You bold like this
$("#nav a").css("font-weight", 400); // First you make them thin
$(this).css("font-weight", 800); // Than you make them bold
You put placeholder like this
<div id="placeholder">
Placeholder
</div>
$("#placeholder").hide();
On the other hand I recommend you not to hide menu container. Rather hide the elements inside the menu_container. So you can put a plcaeholder in menu container and you can hide it.
To figure this out 2 questions must be asked / solved
how do you normally make text bold on a page... css right?
where do you want those styles to be defined? There are 2 places:
a. You can define it inside the javascript.
b. You can define it inside the projects css through normal methods (inline, external, embedded).
What's the difference? If you define it inside the javascript the code is self-contained. What i mean by that is you can copy/paste the JS code from one project to the next and you don't need to worry about copying related styles from the stylesheets or other sources because it's all in the JQuery that you've written.
In contrast if you define it outside the javascript in the regular places the code may not be self-contained however some find it easier to manage in the scope of that particular project because all your css is contained in one place (external stylesheet typically).
If you want to take option a, see the .css() method
If you want to take option b, see the style manipulation (toggle class in particular)
Note the examples in the above references should get you 90% of the way to understanding it.
Some final words. Learn Jquery, but i advise you to stay away from it as much as possible because it implements DOM thrashing instead of DOM caching (sizzle engine).
This video series will briefly go into why Jquery sucks for performance in the first video and the rest of the series is about how to create modular vanilla JS.
JQuery goes back and searches the DOM every time you need to make a change that is what
$.(*element*) is doing instead of just caching it.
The more nodes you have in the DOM the more processing power is used searching (because it has to go through the entire tree).
Then on top of that the more elements you have to make changes to (say if you use a css class selector) you have to add even more processing on top of that.
All this is fine if you're on a desktop, but what about a mobile platform? Where would you get all this processing power from?... It doesn't exist.
As you may know, the Twitter bootstrap tooltips are not accessible (I.E. they are not being read by screen readers). To make that happen, the following things should be done:
Upon calling the tooltip() function, the generated text element (the one that contains the text of the tooltip) should get a new attribute added to it: aria-hidden="true".
The original element (the one tooltip() has been called on) should get an attribute added to it: aria-describedby="#<tooltip-id>", where tooltip-id refers to the id of the new element that was just created above.
Since the way the Javascript currently works is selecting all the elements with the .tooltip class and applying the tooltip() function to it, I'm wondering how I can do this without modifying the source code of the tooltip() function.
Here is an example of the code for a button:
<span role="button" rel="tooltip" title="Add Youtube Video" class="fancyPostButton span1" tabindex="0" style="-webkit-user-select: none;padding-top: 10px">
<div id="fancyPostVideoPicker" class="fancyPostAttachment videoAttachment glyphicons film centerMe">
<i></i>
</div>
</span>
From the looks of the main example in the Bootstrap docs they are keyboard accessible (i.e. show to keyboard-only users) when used on natively-focusable elements, and they use text-content for the buttons.
So the default Bootstrap examples aren't too bad, if the tooltip text were needed to understand the button (like your example) that is when they create an accessibility issue.
So the main thing is that the button has no content, so a screen reader won't know what it is to start with. (NB: Some screen readers might fall back to the title if it were a native link or button, but you shouldn't rely on that.)
To do a button that shows a font-icon, you need content and the icon, so two elements:
<a href="target.html">
<span class="icon-home" aria-hidden="true"></span>
<span class="alt">Add YouTube Video</span>
</a>
Then use CSS to hide the text offscreen. The ARIA-hidden means that the font character won't be read out.
I would also recommend actually using a button or link, rather than span or div, as then you don't need to use javascript to simulate onclick etc. In this case, you've also got an inline element (span) wrapped around a block element (div) which isn't valid HTML either.
If you use the technique above screen reader users will hear the content of the item anyway, I don't think there is any other text to read out?
If you can't add the hidden text in the source, you could loop through the tooltip elements adding it dynamically.
I am trying to build a progressively enhanced page that works for JS and non-JS users. I would like to hide some form controls initially for JS users, but always show them for non-JS users.
My question is about how to do this without creating a distracting "visible, then instantly hidden" flash of content for JS users.
For example, in the JS version, I want to collapse part of my search form, and instead show a 'click here for extra options' button. I do this as follows:
$(document).ready(function() {
$("#extra-options").hide();
...
$("#show-extra-options").click(function() {
$("#extra-options").slideToggle();
});
});
This works, but it means that for JS users, when the page loads, the extra options are visible for 500ms or so, then they vanish. It's rather distracting.
Is there any sensible way to get around this?
StackOverflow has just suggested this answer: is this sensible? Sorry if this is now a duplicate question, but I figure it's still worth writing this question in my own language, as I didn't find the answer during searching.
Add this in your script tag in the head:
$('html').addClass('js');
Then you can use that to show and hide elements:
.hasJs { display: none; }
.js .hasJs { display: block; }
.js .noJs { display: none; }
You can hide content for either users with or without Javascript:
<div class="hasJs">Some content only visible for JS users.</div>
<div class="noJs">Some content only visible for non-JS users.</div>
As the class and CSS are in the head, the elements will already be styled when they come into existance when the body is parsed.
Demo: http://jsfiddle.net/Guffa/YuAyr/
This is a similar approach to the one in the first answer to the question that you linked to, but this is somewhat cleaner because you don't have to add a class to the html element in the markup, and the code simply adds the class instead of removing it.
How can I change the contents of my paragraph as well as the contents of my list once the link was clicked. reference: http://dummyproto.atspace.co.uk/
once i click woven badges on the navigation carousel i want to change the contents of the p as well as the imaged displayed. Is that possible via javascript? Is it a great alternative rather than creating a bunch of html pages for every page which has the same layout but different contents.
I'm looking forward to detailed solutions.Thanks
You need to modify your HTML a bit first so the content you want to swap out is contained in a single element that is easily selectable (for example wrap a div with a unique class name or id around just the stuff you want to swap out). Then do something like this:
document.getElementById('whateverIdYouGaveTheDiv').innerHTML = "blah blah blah";
maybe you can try jQuery template.
or, change the html when the trigger is clicked by using .click() and .html()
like:
var target_html = "something you want";
$('#trigger').click(function() {
$("#content").html(target_html);
});
Personally, I'd make a div "card" for each of your carousel options containing any images or text you want to go with them. Then I'd set all of them but the first to display: none;. When another link in the carousel is clicked, I'd cycle through the "cards," setting them all to display: none except the one needed (which should have the same number in the order of cards as the carousel item you selected in the order of carousel items), which will be display: block; so that I don't have to store HTML into Javascript variables.