Posts Tagged 'Jquery'

October 16, 2014

#T4 – Tips and Tricks–jQuery Select2

Who doesn’t like a walk down memory lane? In our #T4 series, SoftLayer brings back popular tech tip blog posts. #ThrowbackThursday #T4 #ThrowbackThursdayTechTips

Creating a drop-down menu? Here’s an abridged version of our Tips and Tricks – jQuery Select2 Plugin post from two years ago tomorrow!

Turn your drop-down menu from this:
Option Select

To this:

Pretty Option Select

  1. Download Select2 and upload it to your server.
  2. Add the jQuery library and scripts to the <head> of the page document:
  3. <script src="jquery.js" type="text/javascript"></script> 
    <script src="select2.js" type="text/javascript"></script>
  4. Add Select2's included style sheet:
  5. <link href="select2.css" rel="stylesheet"/>

  6. Before closing the <head> tag, invoke the Select2 function:
  7. <script>
    $(document).ready(function() { $("#selectPretty").select2(); });
    </script>
  8. Then add the #selectPretty ID to the select element you want to improve:
    <select id="selectPretty">
    <option value="Option1">Option 1</option>
    <option value="Option2">Option 2</option>
    <option value="Option3">Option 3</option>
    <option value="Option4">Option 4</option>
    </select>

For questions, comments, or just feel like chatting, contact us at social@softlayer.com.

-Cassandra

September 24, 2014

HTML5 – Back to Basics with a Strong Foundation Pt. 1

If you guys have read any of my other blogs, I’m sure you’ll notice a pattern: rather than discussing opinions or news of new technologies, more often than not, I like to write more in the form of tutorials and hands-on exercises that demonstrate either fundamentals or new tips and tricks that I have learned.

In this blog, I’d like to discuss HTML5. I know, I know, it’s not exactly a subject that’s brand new. However, with as many HTML5 implementations as there are out there, and throughout many discussions, I’ve realized that many of the most talented Web developers have had to return to the basics of HTML5 features and techniques in order to redesign projects the same way they developed them.

Simply put: If we forget what we’ve done and scripted for over two decades with previous HTML versions and return to the basics, we can re-learn a new foundation that is sure to make us stronger developers and smarter engineers.

I. Declaration of Independence … or at least a declaration you don’t have to spend hours memorizing!

One of the most raved about features of HTML5 (and yet one of the simplest new features) is the new Doctype. How many of you had to Google the standard Doctype every single time you started a new project? Or perhaps you kept the tag in a code bin for easy copy/pasting? Well, no more!

The old (4 and below) way:

<!DOCTYPE HTML PUBLIC “=//W3C//DTD HTML 4.01//EN”
http://www.w3.org/TR/html4/strict.dtd>

Of course the actual strict/transitional or html/xhtml would vary depending on your page, but they pretty much worked the same way.

The new HTML5 way:

<!DOCTYPE html>

Done. I know it seems like such a simple thing, but returning to the foundation of what we learned so many years ago and re-learning them in the new HTML5 way will not only strengthen our sites, but it will also build a brand new foundation of flexibility and efficiency. Technology evolves at such a rapid pace that if we don’t keep up, we’re going to be left chasing the wagon of the future.

II. Editable content WITHOUT JavaScript!

HTML5 has added so many advanced features that our need for jQuery can be cut by nearly a third (depending on our requirements of course), which in turn greatly reduces the overhead of the browser’s need to process a ton of jQuery functions. If we utilize just a few of HTML5’s awesome new jQuery-like features, we can speed up our site and keep our .js scripts smaller!

Just for giggles (if you’re not familiar with HTML5’s editable content), give this a try:

<!DOCTYPE html>
 <html>
<head>
    <title>SLayer’s Awesome List</title>
</head>
<body>
    <h1> SLayer’s 5 Most Awesome Bloggers </h1>
        <ul contenteditable=”true”>
            <li>Steve Kinman</li>
            <li>Kevin Hazard</li>
            <li>Gary Kinman</li>
            <li>Matthew Herring</li>
            <li>Mark Quigley</li>
        </ul>
</body>
</html>

Put that into an .html file, and open it up in your favorite browser. You’ll see what should look like this:

A simple list of course. In the years of your career I’m sure you’ve made tens of thousands of these. What’s cool about this list, if you’re not familiar with all of HTML5’s neat little tricks, is that this list is editable. Go ahead and try clicking on the list item and replace the names; even add your own name!

As you can see, I didn’t have the heart to remove any of our most frequent bloggers, so I just appended my name to Mark Quigley (of course, that’s not my true SoftLayer Blog ranking, but one day soon … it shall be!)
This feature may not save the user’s edits, but if you add in some nifty HTML5 storage abilities (local or session), you could have yourself a pretty robust application!

III. Beautiful placeholders to hold a place for my heart.

One of my biggest gripes every time I’d either design or program a user interface (registration, account functionality) was the fact that I would have to integrate a jQuery function just to add a little bit of extra help with the text boxes. Placeholders never worked as they should. Sometimes we just didn’t have enough real estate on the page for the amount of instruction as we needed, which meant another placeholder maker for jQuery.

HTML5 now comes equipped with beautiful support for placeholder text (well, I suppose it depends on your POV on designing/developing forms. If you do it as much as I do, the new placeholders are the holy grail of usable forms!). A very simple preview of what HTML form life was like before HTML5 (without the jQuery function to add text to just one input box):

The fact is: Sometimes we don’t always have the real estate that we would like to provide the user enough instructions to clarify what needs to be done!

This simple form could end up being very confusing for the user. It’s so simple, yet there are several ways to enter a phone number, and depending on the backend, it may only accept one format.

Let’s add a placeholder to that textbox and clear things up:

<input placeholder="(555) 555-5555" type="text" name="phone" id="phone" />

Just by adding the simple placeholder attribute, we have now cleared up exactly what format we need the phone number! Now let’s have a look:

It’s funny how a simple, light-colored demonstration of acceptable input can really beautify a form and increase usability. With the placeholder attribute in place in this example, I’m not even sure it’s necessary to have the instruction text on the right, as we can clearly see we need 10 digits, with parenthesis and dashes.

Well my friends, looking at the word count of this document, it looks like this blog is coming to a close, and I’ve only gone over three of my favorite foundational features of HTML5, so you know what that means … Part 2!

-Cassandra

September 16, 2014

CSS3 Tips and Tricks – Generated Content Without jQuery

If you guys have read any of my past blogs, you know how much I LOVE jQuery, but every good developer knows that if there’s an easier or more efficient way of doing something: DO IT. With all the new developments with CSS3, HTML5, etc. etc., sometimes we have to get back to basics to relearn how to do things more efficiently, so here it goes!

Nearly every website has some form of 2.0/dynamic/generated content nowadays, and if your site doesn’t… well, it probably should catch up! I’ll show you how with some new CSS tricks and how it can reduce a lot of overhead of including the entire jQuery library (which would save you approximately 84kb per page load, assuming you have no other asynchronous/client side functionality you need).

I’ll start off with an easy example, since I know most of you take these examples and let your creativity run wild for your own projects. (Note to self: start a “Code Gone Wild” series.)

Usually this is the part where I say “First, let’s include the jQuery library as always.” Not this time, let’s break the rules!

FIRST, start off your document like any other (with the basic structure, set your DOCTYPE appropriately, i.e. strict vs transitional):

<!DOCTYPE html>
<html>
<head>
</head>
<body>
</body>
</html>

Wow, you can already tell this generated content’s going to be a TON easier than using jQuery (for those of you whom aren’t already jQuery fans).

Now let’s add in a div there; every time we hover over that div, we’re going to display our generated content with CSS. Inside of our div, we’re going to place a simple span, like so:

<!DOCTYPE html>
<html>
<head>
</head>
<body>
     <div class=”slisawesome”>
          <span data-title="Hello Cassandra!">What’s my name?</span>
     </div>
</body>
</html>

As you can see, the span content contains a simple question and the data-title attribute contains the answer to that question.

Now let’s just make this div a little bit prettier before we get into the fancy stuff.

Add some style to the <head> section of our document:

<style>
     .slisawesome  {
          /* Will TOTALLY be making another blog about the cool CSS gradients soon */
          background:linear-gradient(to bottom, #8dd2d9 , #58c0c7);
          padding: 20px;  /* give the box some room to breathe */
          width: 125px;  /* give it a fixed width since we know how wide it should be  */
          margin: 100px auto;  /* move it away from the top of the screen AND center it */
          border: 1px solid black;  /* this is just a little border */
          position: relative;  /* this is to help with our generated content positioning */
     }
</style>

Now you should have something that looks like this:

This is good; this is what you should have. Now let’s make the magic happen and add the rest of our CSS3:

<style>
     .slisawesome  {
          /* Will TOTALLY be making another blog about the cool CSS gradients soon */
          background:linear-gradient(to bottom, #8dd2d9 , #58c0c7);
          padding: 20px;  /* give the box some room to breathe */
          width: 125px;  /* give it a fixed width since we know how wide it should be  */
          margin: 100px auto;  /* move it away from the top of the screen AND center it */
          border: 1px solid black;  /* this is just a little border */
          position: relative;  /* this is to help with our generated content positioning */
     }
     .slisawesome span::before {
          content:attr(data-title); /* assigning the data-title attribute value to the content */
          opacity: 0; /* hiding data-title until we hover over it */
          position: absolute; /* positioning our data-title content */
          margin-top: 50px; /* putting more space between our question and answer */
 
          /* Fancy transitions for our data-title when we hover over our question */
          /* which I’m TOTALLY going to write another blog for ;) If you guys want, of course */
          -webkit-transition:opacity 0.4s; /* determines the speed of the transition */
          transition:opacity 0.4s; /* determines the speed of the transition */
     }
</style>

Now, right now, your page should still look like this:

That’s okay! We still have ONE more step to go:

<style>
     .slisawesome  {
          /* Will TOTALLY be making another blog about the cool CSS gradients soon */
          background:linear-gradient(to bottom, #8dd2d9 , #58c0c7);
          padding: 20px;  /* give the box some room to breathe */
          width: 125px;  /* give it a fixed width since we know how wide it should be  */
          margin: 100px auto;  /* move it away from the top of the screen AND center it */
          border: 1px solid black;  /* this is just a little border */
          position: relative;  /* this is to help with our generated content positioning */
     }
     .slisawesome span::before {
          content:attr(data-title); /* assigning the data-title attribute value to the content */
          opacity: 0; /* hiding data-title until we hover over it */
          position: absolute; /* positioning our data-title content */
          margin-top: 50px; /* putting more space between our question and answer */
 
          /* Fancy transitions for our data-title when we hover over our question */
          /* which I’m TOTALLY going to write another blog for ;) If you guys want, of course */
          -webkit-transition:opacity 0.4s; /* determines the speed of the transition */
          transition:opacity 0.4s; /* determines the speed of the transition */
     }
     /* Drum Roll --------- Here’s our hover magic */
     .slisawesome span:hover::before{
          opacity:1;
     }
     /* Okay… that was a little anticlimactic… losing cool points */
</style>

Despite my anticlimactic adding of “the magic,” we just added a :hover that will show full opacity when we hover, so refresh your page and try it out! You should see something like this when you hover over THE QUESTION:

Of course you could REALLY start getting fancy with this by adding some php variables for the logged in user, or perhaps make it dynamic to location, time, etc. The possibilities are endless, so go… go and expand on this awesome generated content technique!

-Cassandra

September 20, 2013

Building a Mobile App with jQuery Mobile: The Foundation

Based on conversations I've had in the past, at least half of web developers I've met have admitted to cracking open an Objective-C book at some point in their careers with high hopes of learning mobile development ... After all, who wouldn't want to create "the next big thing" for a market growing so phenomenally every year? I count myself among that majority: I've been steadily learning Objective-C over the past year, dedicating a bit of time every day, and I feel like I still lack skill-set required to create an original, complex application. Wouldn't it be great if we web developers could finally get our shot in the App Store without having to unlearn and relearn the particulars of coding a mobile application?

Luckily for us: There is!

The rock stars over at jQuery have created a framework called jQuery Mobile that allows developers to create cross-platform, responsive applications on a HTML5-based jQuery foundation. The framework allows for touch and mouse event support, so you're able to publish across multiple platforms, including iOS, Android, Blackberry, Kindle, Nook and on and on and on. If you're able to create web applications with jQuery, you can now create an awesome cross-platform app. All you have to do is create an app as if it was a dynamic HTML5 web page, and jQuery takes care of the rest.

Let's go through a real-world example to show this functionality in action. The first thing we need to do is fill in the <head> content with all of our necessary jQuery libraries:

<!DOCTYPE html>
<html>
<head>
    <title>SoftLayer Hello World!</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="http://code.jquery.com/mobile/1.3.2/jquery.mobile-1.3.2.min.css" />
    <script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
    <script src="http://code.jquery.com/mobile/1.3.2/jquery.mobile-1.3.2.min.js"></script>
</head>

Now let's create a framework for our simplistic app in the <body> section of our page:

<body>
    <div data-role="page">
        <div data-role="header">
            <h1>My App!</h1>
        </div>
 
        <div data-role="content">
            <p>This is my application! Pretty cool, huh?</p>
        </div>
 
        <div data-role="footer">
            <h1>Bottom Footer</h1>
        </div>
 
    </div>
</body>
</html>

Even novice web developers should recognize the structure above. You have a header, content and a footer just as you would in a regular web page, but we're letting jQuery apply some "native-like" styling to those sections with the data-role attributes. This is what our simple app looks like so far: jQuery Mobile App Screenshot #1

While it's not very fancy (yet), you see that the style is well suited to the iPhone I'm using to show it off. Let's spice it up a bit and add a navigation bar. Since we want the navigation to be a part of the header section of our app, let's add an unordered list there:

<div data-role="header">
    <h1>My App!</h1>
        <div data-role="navbar">
            <ul>
                <li><a href="#home" class="ui-btn-active" data-icon="home" data-theme="b">Home</a></li>
                <li><a href="#softlayer_cool_news" data-icon="grid" data-theme="b">SL Cool News!</a></li>
                <li><a href="#softlayer_cool_stuff" data-icon="star" data-theme="b">SL Cool Stuff!</a></li>
            </ul>
        </div>
    </div>

You'll notice again that it's not much different from regular HTML. We've created a navbar div with an unordered list of menu items we'd like to add to the header: Home, SL Cool News and SL Cool Stuff. Notice in the anchor tag of each that there's an attribute called data-icon which defines which graphical icon we want to represent the navigation item. Let's have a peek at what it looks like now: jQuery Mobile App Screenshot #2

Our app isn't doing a whole lot yet, but you can see from our screenshot that the pieces are starting to come together nicely. Because we're developing our mobile app as an HTML5 app first, we're able to make quick changes and see those changes in real time from our phone's browser. Once we get the functionality we want to into our app, we can use a tool such as PhoneGap or Cordova to package our app into a ready-to-use standalone iPhone app (provided you're enrolled in the Apple Development Program, of course), or we can leave the app as-is for a very nifty mobile browser application.

In my next few blogs, I plan to expand on this topic by showing you some of the amazingly easy (and impressive) functionality available in jQuery Mobile. In the meantime, go grab a copy of jQuery Mobile and start playing around with it!

-Cassandra

March 7, 2013

Script Clip: HTML5 Audio Player with jQuery Controls

HTML5 and jQuery provide mind-blowing functionality. Projects that would have taken hours of development and hundreds of lines of code a few years ago can now be completed in about the time it'll take you to read this paragraph. If you wanted to add your own audio player on a web page in the past, what would it have involved? Complicated elements? Flash (*shudders*)? It was so complicated that most developers just linked to the audio file, and the user just downloaded the file to play it locally. With HTML5, an embedded, cross-browser audio player can be added to a page with five lines of code, and if you want to get really fancy, you can easily use jQuery to add some custom controls.

If you've read any of my previous blogs, you know that I love when I find little code snippets that make life as a web developer easier. My go-to tools in that pursuit are HTML5 and jQuery, so when I came across this audio player, I knew I had to share. There are some great jQuery plugins to play music files on a web page, but they can be major overkill for a simple application if you have to include comprehensive controls and themes. Sometimes you just want something simple without all of that overhead:

Oooh... Ahhh...

That song — Pop Bounce by SoftLayer's very own Chris Interrante — is written in five simple lines of HTML5 code:

<audio style="width:550px; margin: 0 auto; display:block;" controls>
  <source src="http://cdn.softlayer.com/innerlayer/Interrante-PopBounce.ogg" type="audio/ogg">
  <source src="http://cdn.softlayer.com/innerlayer/Interrante-PopBounce.mp3" type="audio/mpeg">
Your browser does not support the audio element.
</audio>

If IE 9+, Chrome 6+, Firefox 3.6+, Safari 5+ and Opera 10+ would all agree on supported file formats for the <audio> tag, the code snippet would be even smaller. I completely geek out over it every time I look at it and remember the days of yore. As you can see, the HTML5 application has some simple default controls: Play, Pause, Scan to Time, etc. As a developers, I couldn't help but look for a to spice it up a little ... What if we want to fire an event when the user plays, pauses, stops or takes any other action with the audio file? jQuery!

Make sure your jQuery include is in the <head> of your page:

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>

Now let's use jQuery to script separate "Play" and "Pause" links ... And let's have those links fire off an alert when they are pressed:

$(document).ready(function(){
  $("#play-button").click(function(){
   $("#audioplayer")[0].play();
   alert('You have played the audio file!');
  })    
 
  $("#pause-button").click(function(){
   $("#audioplayer")[0].pause();
   alert('You have paused the audio file!');
  })    
})

With that script in the <head> as well, the HTML on our page will look like this:

<div class=:"audioplayer">
  <audio id="audioplayer" name="audioplayer" controls loop>
    <source src="http://cdn.softlayer.com/innerlayer/Interrante-PopBounce.ogg" type="audio/ogg">
    <source src="http://cdn.softlayer.com/innerlayer/Interrante-PopBounce.mp3" type="audio/mpeg">
  Your browser does not support the audio element.
  </audio>
 
  <a id="play-button" href="#">Play!</a>
  <a id="pause-button" href="#">Pause!</a>
</div>

Want proof that it works that simply? Boom.

You can theme it any way you like; you can add icons instead of the text ... The world is your oyster. The bonus is that you're using one of the lightest media players on the Internet! If you decide to get brave (or just more awesome), you can explore additional features. You're using jQuery, so your possibilities are nearly limitless. If you want to implement a "Stop" feature (which returns the audio back to the beginning when "Stop" is pressed), you can get creative:

$("#stop-button").click(function(){
    $("#audioplayer")[0].currentTime = 0; // return the audio file back to the beginning
}

If you want to include some volume controls, those can be added in a snap as well:

$("#volumeUp").click(function(){
    $("#audioplayer")[0].volume +=0.1;
}
 
$("#volumeDown").click(function(){
    $("#audioplayer")[0].volume -=0.1;
}

Try it out and let me know what you think. Your homework is to come up with some unique audio player functionality and share it here!

-Cassandra

February 14, 2013

Tips and Tricks – Building a jQuery Plugin (Part 2)

jQuery plugins don't have to be complicated to create. If you've stumbled upon this blog in pursuit of a guide to show you how to make a jQuery plugin, you might not believe me ... It seems like there's a chasm between the "haves" of jQuery plugin developers and the "have nots" of future jQuery developers, and there aren't very many bridges to get from one side to the other. In Part 1 of our "Building a jQuery Plugin" series, we broke down how to build the basic structure of a plugin, and in this installment, we'll be adding some usable functionality to our plugin.

Let's start with the jQuery code block we created in Part 1:

(function($) {
    $.fn.slPlugin = function(options) {
            var defaults = {
                myVar: "This is", // this will be the default value of this var
                anotherVar: "our awesome",
                coolVar: "plugin!",
            };
            var options = $.extend(defaults, options);
            this.each(function() {
                ourString = myVar + " " + anotherVar + " " + coolVar;
            });
            return ourString;
    };
}) (jQuery);

We want our plugin to do a little more than return, "This is our awesome plugin!" so let's come up with some functionality to build. For this exercise, let's create a simple plugin that allows truncates a blob of text to a specified length while providing the user an option show/hide the rest of the text. Since the most common character length limitation on the Internet these days is Twitter's 140 characters, we'll use that mark in our example.

Taking what we know about the basic jQuery plugin structure, let's create the foundation for our new plugin — slPlugin2:

(function($) {
    $.fn.slPlugin2 = function(options) {
 
        var defaults = {
            length: 140,
            moreLink: "read more",
            lessLink: "collapse",
            trailingText: "..."
        };
 
        var options = $.extend(defaults, options);
    };
})(jQuery);

As you can see, we've established four default variables:

  • length: The length of the paragraph we want before we truncate the rest.
  • moreLength: What we append to the paragraph when it is truncated. This will be the link the user clicks to expand the rest of the text.
  • lessLink: What we append to the paragraph when it is expanded. This will be the link the user clicks to collapse the rest of the text.
  • trailingText: The typical ellipses to append to the truncation.

In our jQuery plugin example from Part 1, we started our function with this.each(function() {, and for this example, we're going to add a return for this to maintain chainability. By doing so, we're able to manipulate the segment with methods. For example, if we started our function with this.each(function() {, we'd call it with this line:

$('#ourParagraph').slPlugin2();

If we start the function with return this.each(function() {, we have the freedom to add further manipulation:

$('#ourParagraph').slPlugin2().bind();

With such a simple change, we're able to add method calls to make one massive dynamic function.

Let's flesh out the actual function a little more. We'll add a substantial bit of code in this step, but you should be able to follow along with the changes via the comments:

(function($) {
    $.fn.slPlugin2 = function(options) {
 
        var defaults = {
            length: 140, 
            moreLink: "read more",
            lessLink: "collapse",
            trailingText: "..."
        };
 
        var options = $.extend(defaults, options);
 
        // return this keyword for chainability
        return this.each(function() {
            var ourText = $(this);  // the element we want to manipulate
            var ourHtml = ourText.html(); //get the contents of ourText!
            // let's check if the contents are longer than we want
            if (ourHtml.length > options.length) {
                var truncSpot = ourHtml.indexOf(' ', options.length); // the location of the first space (so we don't truncate mid-word) where we will end our truncation.
 
   // make sure to ignore the first space IF the text starts with a space
   if (truncSpot != -1){
       // the part of the text that will not be truncated, starting from the beginning
       var firstText = ourHtml.substring(0, truncSpot);
 
       // the part of the text that will be truncated, minus the trailing space
       var secondText = ourHtml.substring(truncSpot, ourHtml.legnth -1);
                }
            }
        })
    };
})(jQuery);

Are you still with us? I know it seems like a lot to take in, but each piece is very straightforward. The firstText is the chunk of text that will be shown: The first 140 characters (or whatever length you define). The secondText is what will be truncated. We have two blobs of text, and now we need to make them work together:

(function($) {
    $.fn.slPlugin2 = function(options) {
 
        var defaults = {
            length: 140, 
            moreLink: "read more",
            lessLink: "read less",
            trailingText: "..."
        };
 
        var options = $.extend(defaults, options);
 
        // return this keyword for chainability
        return this.each(function() {
            var ourText = $(this);  // the element we want to manipulate
            var ourHtml = ourText.html(); //get the contents of ourText!
            // let's check if the contents are longer than we want
            if (ourHtml.length > options.length) {
                var truncSpot = ourHtml.indexOf(' ', options.length); // the location of the first space (so we don't truncate mid-word) where we will end our truncation.
 
   // make sure to ignore the first space IF the text starts with a space
   if (truncSpot != -1){
       // the part of the text that will not be truncated, starting from the beginning
       var firstText = ourHtml.substring(0, truncSpot);
 
       // the part of the text that will be truncated, minus the trailing space
       var secondText = ourHtml.substring(truncSpot, ourHtml.legnth -1);
 
       // perform our truncation on our container ourText, which is technically more of a "rewrite" of our paragraph, to our liking so we can modify how we please. It's basically saying: display the first blob then add our trailing text, then add our truncated part wrapped in span tags (to further modify)
       ourText.html(firstText + options.trailingText + '<span class="slPlugin2">' + secondText + '</span>');
 
       // but wait! The secondText isn't supposed to show until the user clicks "read more", right? Right! Hide it using the span tags we wrapped it in above.
       ourText.find('.slPlugin2').css("display", "none");
                }
            }
        })
    };
})(jQuery);

Our function now truncates text to the specified length, and we can call it from our page simply:

<script src="jquery.min.js"></script>
<script src="jquery.slPlugin2.js"></script>
<script type="text/javascript">
$(document).ready(function() {  
    $('#slText').slPlugin2();  
});
</script>

Out of all the ways to truncate text via jQuery, this has to be my favorite. It's feature-rich while still being fairly easy to understand. As you might have noticed, we haven't touched on the "read more" and "read less" links or the expanding/collapsing animations yet, but we'll be covering those in Part 3 of this series. Between now and when Part 3 is published, I challenge you to think up how you'd add those features to this plugin as homework.

-Cassandra

January 10, 2013

Web Development - JavaScript Packaging

If you think of JavaScript as the ugly duckling of programming languages, think again! It got a bad rap in the earlier days of the web because developers knew enough just to get by but didn't really respect it like they did Java, PHP or .Net. Like other well-known and heavily used languages, JavaScript contains various data types (String, Boolean, Number, etc.), objects and functions, and it is even capable of inheritance. Unfortunately, that functionality is often overlooked, and many developers seem to implement it as an afterthought: "Oh, we need to add some neat jQuery effects over there? I'll just throw some inline JavaScript here." That kind of implementation perpetuates a stereotype that JavaScript code is unorganized and difficult to maintain, but it doesn't have to be! I'm going to show you how easy it is to maintain and organize your code base by packaging your JavaScript classes into a single file to be included with your website.

There are a few things to cover before we jump into code:

  1. JavaScript Framework - Mootools is my framework of choice, but you can use whatever JavaScript framework you'd like.
  2. Classes - Because I see JavaScript as another programming language that I respect (and is capable of object-oriented-like design), I write classes for EVERYTHING. Don't think of your JavaScript code as something you use once and throw away. Write your code to be generic enough to be reused wherever it's placed. Object-oriented design is great for this! Mootools makes object-oriented design easy to do, so this point reinforces the point above.
  3. Class Files - Just like you'd organize your PHP to contain one class per file, I do the exact same thing with JavaScript. Note: Each of the class files in the example below uses the class name appended with .js.
  4. Namespacing - I will be organizing my classes in a way that will only add a single property — PT — to the global namespace. I won't get into the details of namespacing in this blog because I'm sure you're already thinking, "The code! The code! Get on with it!" You can namespace whatever is right for your situation.

For this example, our classes will be food-themed because ... well ... I enjoy food. Let's get started by creating our base object:

/*
---
name: PT
description: The base class for all the custom classes
authors: [Philip Thompson]
provides: [PT]
...
*/
var PT = {};

We now have an empty object from which we'll build all of our classes. We'll go I will go into more details later about the comment section, but let's build our first class: PT.Ham.

/*
---
name: PT.Ham
description: The ham class
authors: [Philip Thompson]
requires: [/PT]
provides: [PT.Ham]
...
*/
 
(function() {
    PT.Ham = new Class({
        // Custom code here...
    });
}());

As I mentioned in point three (above), PT.Ham should be saved in the file named PT.Ham.js. When we create second class, PT.Pineapple, we'll store it in PT.Pineapple.js:

/*
---
name: PT.Pineapple
description: The pineapple class
authors: [Philip Thompson]
requires: [/PT]
provides: [PT.Pineapple]
...
*/
 
(function() {
    PT.Pineapple = new Class({
        // Custom code here...
    });
}());

Our final class for this example will be PT.Pizza (I'll let you guess the name of the file where PT.Pizza lives). Our PT.Pizza class will require that PT, PT.Ham and PT.Pineapple be present.

/*
---
name: PT.Pizza
description: The pizza class
authors: [Philip Thompson]
requires: [/PT, /PT.Ham, /PT.Pineapple]
provides: [PT.Pizza]
...
*/
 
(function() {
    PT.Pizza = new Class({
        // Custom code here that uses PT.Ham and PT.Pineapple...
    });
}());

Before we go any further, let's check out the comments we include above each of the classes. The comments are formatted for YAML — YAML Ain't Markup Language (you gotta love recursive acronyms). These comments allow our parser to determine how our classes are related, and they help resolve dependencies. YAML's pretty easy to learn and you only need to know a few basic features to use it. The YAML comments in this example are essential for our JavaScript package-manager — Packager. I won't go into all the details about Packager, but simply mention a few commands that we'll need to build our single JavaScript file.

In addition to the YAML comments in each of the class files, we also need to create a YAML file that will organize our code. This file — package.yml for this example — is used to load our separate JavaScript classes:

name: "PT"
description: "Provides our fancy PT classes"
authors: "[Philip Thompson]"
version: "1.0.0"
sources:
    - js/PT.js
    - js/PT.Ham.js
    - js/PT.Pineapple.js
    - js/PT.Pizza.js

package.yml shows that all of our PT* files are located in the js directory, one directory up from the package.yml file. Some of the properties in the YAML file are optional, and you can add much more detail if you'd like, but this will get the job done for our purposes.

Now we're ready to turn back to Packager to build our packaged file. Packager includes an option to use PHP, but we're just going to do it command-line. First, we need to register the new package (package.yml) we created for PT. If our JavaScript files are located in /path/to/web/directory/js, the package.yml file is in /path/to/web/directory:

./packager register /path/to/web/directory

This finds our package.yml file and registers our PT package. Now that we have our package registered, we can build it:

./packager build * > /path/to/web/directory/js/PT.all.js

The Packager sees that our PT package is registered, so it looks at each of the individual class files to build a single large file. In the comments of each of the class files, it determines if there are dependencies and warns you if any are not found.

It might seem like a lot of work when it's written out like this, but I can assure you that when you go through the process, it takes no time at all. The huge benefit of packaging our JavaScript is evident as soon as you start incorporating those JavaScript classes into your website ... Because we have built all of our class files into a single file, we don't need to include each of the individual JavaScript files into our website (much less include the inline JavaScript declarations that make you cringe). To streamline your implementation even further if you're using your JavaScript package in a production deployment, I recommend that you "minify" your code as well.

See ... Organized code is no longer just for server-side only languages. Treat your JavaScript kindly, and it will be your friend!

Happy coding!

-Philip

November 27, 2012

Tips and Tricks - Building a jQuery Plugin (Part 1)

I've written several blogs detailing the use of different jQuery plugins (like Select2, LazyLoad and equalHeights), and in the process, I've noticed an increasing frustration among the development community when it comes to building jQuery plugins. The resources and documentation I've found online have not as clear and easy as they could be, so in my next few posts, I'll break down the process to make jQuery plugin creation simple and straightforward. In this post, we'll cover the basic structure of a plugin and where to insert your own functionality, and in Part 2, we'll pick a simple task and add on to our already-made structure.

Before I go any further, it's probably important to address a question you might be asking yourself: "Why would I want to make my own plugin?" The best reason that comes to my mind is portability. If you've ever created a large-scale project, take a look back into your source code and note how many of the hundreds of lines of jQuery code you could put into a plugin to reuse on a different project. You probably invested a lot of time and energy into that code, so it doesn't make sense to reinvent the wheel if you ever need that functionality again. If that's not enough of a reason for you, I can also tell you that if you develop your own jQuery plugin, you'll level-up in cool points, and the jQuery community will love you.

For this post, let's create a jQuery plugin that simply returns, "This is our awesome plugin!" Our first step involves putting together the basic skeleton used by every plugin:

(function($) {
    $.fn.slPlugin = function() {
 
            // Awesome plugin stuff goes here
    };
}) (jQuery);

This is your template — your starting point. Practice it. Remember it. Love it. The "slPlugin" piece is what I chose to name this plugin. It's best to name your plugin something unique ... I always run a quick Google search to ensure I don't duplicate the name of a plugin I (or someone else) might need to use in a project alongside my plugin. In this case, we're calling the example plugin slPlugin because SoftLayer is awesome, and I like naming my plugins after awesome things. I'll save this code in a file called jquery.slPlugin.js.

Now that we have our plugin's skeleton, let's add some default values for variables:

(function($) {
    $.fn.slPlugin = function(options) {
            var defaults = {
                myVar: "default", // this will be the default value of this var
                anotherVar: 0,
                coolVar: "this is cool",                
            };
            var options = $.extend(defaults, options);
    };
}) (jQuery);

Let's look at the changes we made between the first example and this one. You'll notice that in our second line we added "options" to become $.fn.slPlugin = function(options) {. We do this because our function is now accepting arguments, and we need to let the function know that. The next difference you come across is the var defaults blurb. In this section, we're providing default values for our variables. If you don't define values for a given variable when you call the plugin, these default values will be used.

Now let's have our plugin return the message we want to send:

(function($) {
    $.fn.slPlugin = function(options) {
            var defaults = {
                myVar: "This is", // this will be the default value of this var
                anotherVar: "our awesome",
                coolVar: "plugin!",
            };
            var options = $.extend(defaults, options);
            this.each(function() {
                ourString = myVar + " " + anotherVar + " " + coolVar;
            });
            return ourString;
    };
}) (jQuery);

We've defined our default values for our variables, concatenated our variables and we've added a return under our variable declaration. If our jQuery plugin is included in a project and no values are provided for our variables, slPlugin will return, "This is our awesome plugin!"

It seems rather rudimentary at this point, but we have to crawl before we walk. This introductory post is laying the groundwork of coding a jQuery plugin, and we'll continue building on this example in the next installment of this series. As you've seen with the LazyLoad, equalHeights and Select2, there are much more complicated things we can do with our plugin, and we'll get there. Sneak Preview: In the next installment, we'll be creating and implementing a truncation function for our plugin ... Get excited!

-Cassandra

October 17, 2012

Tips and Tricks - jQuery Select2 Plugin

Web developers have the unique challenge of marrying coding logic and visual presentation to create an amazing user experience. Trying to find a balance between those two is pretty difficult, and it's easy to follow one or the other down the rabbit hole. What's a web developer to do?

I've always tried to go the "work smarter, not harder" route, and when it comes to balancing functionality and aesthetics, that usually means that I look around for plugins and open source projects that meet my needs. In the process of sprucing up an form, I came across jQuery Select2, and it quickly became one of my favorite plugins for form formatting. With minimal scripting and little modification, you get some pretty phenomenal results.

We've all encountered drop-down selection menus on web forms, and they usually look like this:

Option Select

Those basic drop-downs meet a developer's need for functionality, but they aren't winning any beauty pageants. Beyond the pure aesthetic concerns, when a menu contains dozens (or hundreds) of selectable options, it becomes a little unwieldy. That's why I was so excited to find Select2.

With Select2, you can turn the old, plain, boring-looking select boxes into beautiful, graceful and more-than-functional select widgets:

Pretty Option Select

Not only is the overall presentation of the data improved, Select2 also includes an auto-complete box. A user can narrow down the results quickly ad easily, and if you've got some of those endlessly scrolling select boxes of country names or currencies, your users will absolutely notice the change (and love you for it).

What's even sexier than the form facelift is that you can add the plugin to your form in a matter of minutes.

After we download Select2 and upload it to our box, we add our the jQuery library and scripts to the <head> of our document:

<script src="jquery.js" type="text/javascript"></script> 
<script src="select2.js" type="text/javascript"></script>

For the gorgeous styling, we'll also add Select2's included style sheet:

<link href="select2.css" rel="stylesheet"/>

Before we close our <head> tag, we invoke the Select2 function:

<script>
$(document).ready(function() { $("#selectPretty").select2(); });
</script>

At this point, Select2 is locked and load, and we just have to add the #selectPretty ID to the select element we want to improve:

<select id="selectPretty">
<option value="Option1">Option 1</option>
<option value="Option2">Option 2</option>
<option value="Option3">Option 3</option>
<option value="Option4">Option 4</option>
</select>

Notice: the selectPretty ID is what we defined when we invoked the Select2 function in our <head> tag.

With miniscule coding effort, we've made huge improvements to the presentation of our usually-boring select menu. It's so easy to implement that even the most black-and-white coding-minded web developers can add some pizzazz to their next form without having to get wrapped up in styling!

-Cassandra

September 26, 2012

Tips and Tricks - jQuery Lazy Load Plugin

In the late 90's, web pages presented their information in a relatively structured fashion, with little concern on how "pretty" the content looked. To a certain extent, that was a result of available technology and resources being a little more limited, but much of the reason was probably because we had no idea what was possible. We've come a long way, my friend. These days, it's tough to spend an hour online without coming across a gorgeous web site with huge animations, a pallet of every color possible, full-width backgrounds and high definition detail.

Those sites may be aesthetically pleasing, but they can be a big pain from a developer's perspective.

How much load does all of that stuff put on the server every time that web page is visited? As developers, it's our job to think about both what the visitor sees AND the visitor's experience in seeing it. Even the most beautiful sites will be ignored if a page takes too long to load. We spend hours optimizing every detail so users can fluidly browse without having to wait. It was in one of these optimization sessions that I discovered "lazy load."

To be honest, I wasn't too fond of the word "lazy" in the name, and I especially wasn't fond of having to explain to my boss that *I* wasn't being lazy ... The jQuery plugin is *named* "Lazy Load." Lazy Load effectively allows large pieces of content to stay in the backlog until they're needed. To give you an example of what that looks like, let's say you have a website with three humungous images, but they're all in different locations. Instead of pushing the entire load onto the user when they first land on your page, we can break them up and have them load only when the user goes to view them. We're not reducing the size of the web page; we're merely helping it work smarter.

Without Lazy Load, a normal web page loads each item when its page is visited. If a website has videos, music, images and some neat user interactivity applications, each of those items will load at the same time:

Lazy Load Illustration

If you take into consideration how large each of those items are, you can sense the problem. The user only has so much bandwidth to load these items, and something's gotta give. Usually, it means long loading times. We can't control how fast each user's ISP is, but we can reorder our items and let Lazy Load help us prioritize items and load the page more efficiently.

After we snag Lazy Load on Github (jquery.lazyload.js), we put our jQuery scripts in the <head> of our page:

<script src="jquery.js" type="text/javascript"></script> 
<script src="jquery.lazyload.js" type="text/javascript"></script>

Now that the plugin is available to us, we need to determine what we want to load lazily. Images are probably one of the most bothersome page elements, so let's apply Lazy Load to the images we load in the belazy class. In the <head> of your page (or in the footer if you prefer your JavaScript entries there), you'll add:

<script type="text/javascript">$("img.belazy").lazyload();</script>

As a result of that function, all image tags with a class of belazy will have Lazy Load run on them. This helps us ensure that we're not loading ALL of our images lazily. Now we need to choose which images we want to apply Lazy Load to.

Let's say the image tag of the largest image on one of our page looks like this:

<img src="bighonkingimage.png"/>

To have the lazyload function apply to it, we just have to make a couple tweaks:

<img class="belazy" src="bighonkingimage.png" data-original="bighonkingimage.png"/>

We added class="belazy" to trigger the lazyload function, and we added data-original="bighonkingimage.png" to line up with the formatting required by the newest version of Lazy Load (it's simply a repeat of the source).

When a user visits our page, bighonkingimage.png will load only when it's needed!

Pretty neat, eh?

-Cassandra

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