Questions about JavaScript and a vertical, multi-level navigation bar - javascript

Is it possible to make a vertical, multi-level navigation bar using only CSS and WITHOUT using JavaScript?
Like the one in here:
http://www.dhtmlgoodies.com/scripts/slidedown-menu2/slidedown-menu2.html#
I am trying to avoid using JavaScript because browsers today has an option that can disable JavaScript codes. I don't want my webpages to be broken because of that settings. Should I even be thinking about this? Or should I just use JavaScript anyway?
I was hoping on using only CSS for this, though I'm not sure if CSS is enough for this.
EDIT: By the way, is there a CSS selector when you click an <a> tag? Something like 'a:click'. I only know a:hover.

You won't be able to have any sort of animation like that example, unless you use CSS3 animations, in which case you will have LESS support than if you used JavaScript.
If it were me, I would just use JavaScript to do it. If the user has it turned off, they will still receive the menu, just not the animation (if you code it correctly).

There are some examples here of what you can do with CSS:
http://www.cssmenus.co.uk/dropdown.html

CSS is mainly for styling your webpages, while JavaScript is mainly for giving them different behaviors and interactivity.
That said, CSS3 is doing a lot to change that. But, if you want a web page with any kind of Cross- browser support currently, that's not really an option.
Like you have said, users have the option of disabling JavaScript, which is a good thing for security. This, however, means that you should always try to make any JavaScript supplementary to your page, so there is still some functionality even if JavaScript is disabled.
If you want any interesting effects in your menu, you will need some mix of CSS and JavaScript, and if you define and apply your styles within your CSS documents and not from within your JavaScript, you will still sustain some level of usability

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When should I control background image change with CSS vs Javascript? [closed]

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This is more of a general practice question that a problem specific one but I'll give an example of what I mean. There are a lot of things you can control with CSS that you can also do with Javascript, but is one better to lean on than the other?
Example:
I have four buttons in a nav that are given a class of "selected" when the section they're associated with is in view. So I could either write a CSS statement for each button (or have Sass do it for me with a mixin)
#home-butt.selected{
background-image: url(images/home-up.png);}
#about-butt.selected{
background-image: url(images/about-up.png);}
#work-butt.selected{
background-image: url(images/work-up.png);}
#contact-butt.selected{
background-image: url(images/contact-up.png);}
Orrr I could write something in javascript to do the same thing. (*I gave the images a title attribute that matched the image name so it could pull from there).
title = $(this).attr('title');
$(this).find('img').css("background-image",
"url(" + 'images/' + (title) + '-up.png' + ")");
So my question is which is better to use? Is it the javascript because it's less lines of code? Or the CSS incase javascript is disabled? Or is this a very situational question where there isn't always a right or wrong answer?
Opinions and rebuttals are welcome!
To answer your question about "is one better to lean on than the other?"
Keep in mind, that CSS has a specific purpose. To apply the look to your application. JavaScript on the otherhand, is mostly the feel of your app. Always prefer CSS over JavaScript when editing styles.
The only time that you ever should modify styles using JavaScript is when you have a dynamic application, and need to change styles based on some unknown variable. Even then, a lot can be achieved with just using CSS.
Also keep in mind that you are using jQuery. think about jQuery's constructor. it is a CSS selector.
With the concept of CSS pseudo-classes introduced, there is very little that you cannot achieve style-wise with CSS.
In many cases where Javascript developing makes what I'm trying to accomplish much more easy and other cases where CSS does that to.
" In the end each "language" has its appropriate place in web development and used wisely can enhance both development and user experience. Learn what those uses are (I recommend experience learning) and apply wisely. In my experience, set in stone rules such as "Never use JS when a CSS solution exists" (paraphrased) are rarely best in the practical world. "
If you are working with layout, use CSS, if your creating the look and feel use CSS, if your doing animations use CSS3
If you attach event handlers or reacting to user input use JavaScript.
Usually you want to use CSS, because it's much faster than javascript. Also there are going to be users with javascript disabled, which aren't going to see your enhanced presentation if it relied on js function.
The usual answer is, use CSS when you can, because it will work with JavaScript disabled, and also because you don't have to deal with issues like waiting for elements being available in the DOM before referencing them.
But sometimes it depends. Keep in mind that:
Depending on the selector or properties you're changing you may have issues with browser compatibility.
If you're changing the image like in your example, you may see it flicker while the new image is loaded. You can avoid that by using a sprite image, or preloading the images with JavaScript.
As a general rule of thumb, I would use CSS for styling and JavaScript only to "make the page alive".
So the best and the most ideal use of JavaScript is to add and remove classes from elements
- classes, which your CSS is depend on.
Loading the jQuery library to perform this simple task is unnecessary and relying on javascript to apply background images to your img tags is unnecessary as well.
If it can be done properly in CSS, and work in all browsers, then it should be done in CSS.
Javascript is for more advanced or complex tasks, which require interaction or animations that CSS can't provide for all browsers (due to cross browser compatibility issues - check out caniuse.com)
In your example, if the .selected attribute is being given dynamically by javascript for instance:
makeSelected(elm)
{
document.getElementById(elm).className='selected';
}
then i would still personally add the styling for .selected in CSS instead of adding the image through javascript.
If you're adding .selected based on the current page you're on and not through javascript then I would recommend using CSS.
I prefer CSS over Script for one main reason Browser compatibility
There are just soooo many times when one script code or the other isn't compatible in one browser or the other (cough or just IE)
With css I haven't had such issues yet (touchwood) and also if there were any issues CSS's won't affect as much as script's which just don't let any other following codes to execute.
Let me provide my opinion.
Personally I don't believe a website should have a lot of "gimmicks" in terms of designing.
BY gimmicks I mean hovering effects, music in the background(absolute no-no) or other "eye-catching details". All of this looks good the first time but subsequently visitors get fed up with this distractions.
Without deviating from the main issue. CSS/JavaScript for styling.
Well they do exist hand in hand. The best example for this would be Bootstrap library. Although I have never used it personally but it seems amazing what can be achieved using CSS and JavaScript.
So, We will need both to design spectacular website. CSS helps in the basic designing and to make the website more responsive we use JavaScript and its derivative libraries like Jquery for all the finer looking stuff

Simple lightbox feedback form? Included screenshot

There are so many lightboxes to choose from, I'm looking for a very lightweight one to use in an embedded javascript widget that would be a single domain name. I saw the perfect one on chainreactioncycles.com, it popped up out of nowhere so I took a screenshot:
I tried looking for info on it on the page source, but couldn't find anything that would let me trace where it came from... Would anybody know of one like this? Or exactly that one?
If not exactly like above, anything similar would be great too, keeping the following in mind:
Very small javascript download (animation not needed)
Self contained, not dependent on any libraries other than jquery (since I'm already using that anyway).
Works in major browsers
Close button (like GetSatisfaction or UserVoice)
Dims background
Avoids javascript namespace conflicts (or can easily be made to avoid them)
CSS styling of lightbox does not interfere with site styling
Have you used an existing lightbox scripts for this same purpose with similar requirements? Did you roll your own? Insights welcome!
What you are looking for is called a modal box.
Here is a list of them
... and here is a striking replica of what you are looking for
Check out Zoombox.. It sounds like what you're looking for... Simple to use... Allows custom content.. jQuery Module... From past experience it covers what you have outlined as requirements etc
http://www.grafikart.fr/zoombox will tell you all you need to know.

Javascript widget implementation

I have a question about Javascript widgets. The widget I am working on simply embeds content on a page instead of using iframes. So far it looks good. But there are cases where some users layouts are messing up the widget. For example, the widget might require a width of 300px to appear. But the parent div is set to 250px and hence the right part of the widget is cut off.
I was wondering what sort of precautions should be taken to prevent this? I was talking to the product manager who mentioned he wanted me to check the parent div elements and get the size and then show an alternate message if their size is not accurate. But again, since this is Javascript and the widget is supported in many diff browsers(including IE6), I am wondering how fail-safe this method would be? What if I need to iterate the DOM all the way up before getting a valid size? I am also worried about performance here. This extra checks would slow down the delivery of my widget content to "good users" since I am adding a layer of complexity to all users. I don't want to penalize good users just because of the few errant ones.
I am not using any sort of JS library here, so any solution should not suggest the use of one. Also, the reason for not using a library was simply not to add extra weight to the page load to deliver a widget. I understand that "jquery" for example is small, but in my case, even 24k compressed seems like an overkill for a widget delivery that contains no core code for the widget.
Has anyone dealt with such issues before? What are your solutions to these?
There are reliable ways of determining the size of an element using JavaScript. You're quite right that you may need to iterate up the tree in some cases, but the answer you get will ultimately be quite valid.
Although you don't want to directly include any library code in this project, you may consider looking at how the major libraries implement their "what's the width of this element" functions to drive your own implementation.
Beware of quirks mode too.
I'd check to see of the page has Jquery, if not load it into the page using no-conflict mode. Then use jQuery to examine the page.
See: How to embed Javascript widget that depends on jQuery into an unknown environment

What happens to my web application if JavaScript is disabled?

I'm learning jQuery and am about to write some pages using intensively that library. I just learned that some user disable JavaScript on their browser (I didn't even know that was possible and/or necessary).
Now, here's my question: What happens to my web application if a user disable JavaScript? For instance, I'd like to display some screens using AJAX and commands such as 'InsertBefore' to bring in live a DIV that will display the result.
So, if JavaScript is disabled, I wonder what going to happen to all this work that relies on JavaScript?
I'm kind of lost.
Thanks for helping
You may want to start by reading on Progressive Enhancement and Unobtrusive JavaScript.
I would also suggest to investigate how popular rich web applications like GMail, Google Maps and others, handle these situations.
I just learned that some user disable javascript on their browser
I do. The "NoScript" plugin for FireFox does the trick.
So, if Javascript is disabled, I wonder what going to happen to all this work that relies on Javascript?
It won't be functional.
A good practice suggests designing a site not to rely on JavaScript for major functionality. At least, accessing its content (in read-mode) should be possible. JavaScipt should only add interface enhancements like Ajax techniques etc. But the fallback version should always work.
I feel really sad when I see a site which is completely broken without JavaScript. Why can't people use CSS to put elements in proper places? Why do they try to align elements with JavaScript even if there is no dynamics involved?
The same goes for Flash sites. Once in a while a land upon a "web-design-agency" site which makes picky comments about me not allowing JavaScript. When I do I only see a basic primitive site with a few menus and that's it. What was the point of using Flash when the work is so primitive it can be done with raw HTML and CSS in an hour? For me it's a sign of unprofessional work.
All what's done in JavaScript won't work. Some users disable it for security reasons, NoScript is an excellent example. You can try it yourself by removing the scripts from your page or installing the NoScript-plugin for Firefox.
As a rule of thumb:
Make the website working with only semantic HTML
add the CSS
add the JS
But the website should be (almost) fully functional in stage 1.
If you disable Javascript in Safari things like Lexulous in Facebook won't work properly, the mouse letter carry function doesn't work.

Site nav when javascript is disabled

We have a nav that expands on rollover (based on this code: http://www.dynamicdrive.com/dynamicindex1/droptabmenu.htm).
First, should we have a no-javascript version of the nav?
If yes, what is the best way to do so?
Yes you should always have a non-javascript version of your navigation.
The best way to do this is to apply any styles that hide sub-menus with javascript - so if the javascript isn't run the whole menu will be visible.
The HTML for the menu you've linked to looks fine - <ul>s and <a>s - nice and easy for a spider or non-javascript user to read.
It's always a good idea to have a no-Javascript version of everything.
Search engine robots usually do not interpret Javascript, so your pages might not be indexed if they can't be reached without Javascript.
A sitemap page that simply has a link to every static page on your site is the easiest way to make sure everyone can get to anywhere.
You may want to use unobtrusive javascript, which basically means have no javascript in your html page, just load the javascript files.
Now, if you start with a menu on the left, for navigation, using <li> and anchor tags then you can have some navigation without javascript.
So, if your javascript runs, the first thing it should do, when the dom tree is ready, is to set display: none on the navigation div and put in the new, more interactive navigation bar.
This way you can see how it works without any javascript.
Or, you can have a message telling them that javascript is required and do nothing else, but this would also be hidden as above.
I prefer to have things work, even if it has less functionality, without javascript, when possible.
Don't get me wrong: It's a good idea to support browsers that don't have JavaScript turned on, especially for something as simple as a menu.
However, when a project doesn't have it in the budget, or the application that you're writing is deeply dependent on JavaScript, it just doesn't make sense to support it.
Statistic from w3c and the counter indicate that 93% to 95% of users have JavaScript enabled. Now, mind you that this is a global demographic. To really determine if it's worth your time and money, it would behoove you to do your own statistics to determine what percentage of your traffic/demographic has JavaScript enabled.
As a side note: for reasons similar to why people are moving away from supporting IE 6, my company is also moving away from noscript support. Especially in large scale RIA's, it's just not practical to write the same thing twice. Maintaining two code bases for one project is not my idea of a good time. But of course, this is always based on the client and the target demographic.

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