basics.html

---
index: 1
title: jQuery tools basics
---

{% block blurb %}
<h2 class="first">In this document</h2>

<p>
  This document describes common practices for each of the tools such
  as:
</p>

<ul>
  <li><a href="#html">The role of HTML</a></li>
  <li><a href="#jquery">The role of JavaScript and jQuery</a></li>
  <li><a href="#css">The role of CSS</a></li>
  <li><a href="#graphics">Graphic design and Presentation</a></li>
  <li><a href="#include">Including the Tools</a></li>
  <li><a href="#initialize">Initializing the Tools</a></li>
  <li><a href="#global_configuration">Using global configurations</a></li>
  <li><a href="#extending">Using jQuery Tools plugins and effects</a></li>
</ul>

{% endblock %}

{% block content %}
<a name="html"></a>
<h2>The role of <em>HTML</em></h2>

<p>
  jQuery Tools was primarily developed for "normal" HTML
  developers. You either have an existing website or are starting with
  a new one and these tools are used to enhance it. The goal here is
  to use "progressive enhancement" so that browsers that do not
  support JavaScript at all can still visualize your content.
</p>

<p>
  These tools are not bound to any specific HTML structure. For
  example, tabs can be constructed
  from <samp>ul</samp>, <samp>ol</samp>, <samp>dl</samp>, <samp>div</samp>
  or <samp>table</samp> elements. The same is true of our other jQuery
  Tools as well. The most important thing is to <em>understand</em>
  what you are doing and what HTML element is suitable for which
  specific situation.
</p>

<p>
  All of the tools deal with a <em>root element</em> which is
  typically a <samp>div</samp> element, but it does not have to
  be. For example, a root element for an overlay is the one that
  contains all overlayed data. In every tool you can have <em>any</em>
  combination of HTML inside the root element such as images, forms,
  Flash objects and tables.
</p>


<a name="jquery"></a>
<h2>The role of <em>JavaScript</em> and <em>jQuery</em></h2>

<p>
  <a href="http://www.jquery.com" class="external">jQuery</a> is a
  fast and concise JavaScript library that simplifies the development
  of cross-browser applications. All <samp>tools</samp>
  except <a href="flashembed.html">flashembed</a> are dependent on
  this library. jQuery skills are <strong>not required</strong> when
  using these tools. People have been using these tools without any
  prior knowledge about jQuery and even JavaScript itself. Of course,
  those skills would be a great help, but they are not required.
</p>

<p>
  If you want to enhance your jQuery and JavaScript skills, the best
  things to learn about when using these tools would definitely
  be <a href="http://api.jquery.com/category/selectors/"
  class="external">jQuery selectors</a>
  and <a href="http://www.dyn-web.com/tutorials/obj_lit.php"
  class="external">object literals</a>. The first skill is used to
  select elements from the page to be enhanced with the tools and the
  latter is used for configuring the tools. Here is an example that
  introduces you to both of these skills:
</p>

{% filter syntax('js') %}
  // two jquery selectors and a configuration given as an object literal
  $("#content ul.tabs").tabs("div.panes > div", {

  // configuration variables
  current: 'current',
  effect: 'fade'

  });
{% endfilter %}

<p>
  Here we have two jQuery selectors. The first one selects
  all <samp>ul</samp> elements whose class name is <samp>tabs</samp>
  which are all contained inside an element whose <samp>id</samp> is
  "content". This query is similar to CSS selectors and if you know
  CSS, you will feel at home here. The second selector selects
  all <samp>div</samp> elements that are directly nested inside
  a <samp>div</samp> whose class name is <samp>panes</samp>.
</p>

<p>
  Finally, we have a configuration object starting with <samp>{</samp>
  and ending with <samp>}</samp>. It contains a comma-separated list
  of name-value pairs. The name is followed by a colon which is
  followed by a value. The value can be a number, string, boolean,
  array, function or another object literal. Care must be taken to
  enclose string values in quotes. That is about it. You use this
  syntax to configure these tools.
</p>

<a name="document_ready"></a>
<h3>Execute your scripts when the document is ready</h3>

<p>
  It is important that you execute all your scripts only after the
  document is ready and scriptable. This can be done by enclosing your
  JavaScript calls inside a <samp>$(document).ready()</samp> block as
  follows:
</p>

{% filter syntax('js') %}
  $(document).ready(function() {

  // put all your JavaScript wizardry here

  });
{% endfilter %}

<p>
  This might be the most important thing in jQuery. Everything inside
  the block will load as soon as the document is scriptable
  but <em>before</em> the whole page contents such as images and Flash
  are loaded. Everything that you stick inside the braces is ready to
  go at the earliest possible moment. And as opposed to the
  traditional old-school "onload" attribute in the <samp>body</samp>
  tag you can have multiple <samp>$(document).ready()</samp> blocks on
  your page.
</p>

<p>
  You can also use a shorter syntax:
</p>

{% filter syntax('js') %}
  $(function() {

  // same thing here.

  });
{% endfilter %}

<p>
  Which does exactly the same thing but is not so intuitive for a
  newcomer.
</p>


<a name="css"></a>
<h2>The role of <em>CSS</em></h2>

<p>
  Cascaded Style Sheets (CSS) are the industry standard for styling
  the presentation and positioning of your elements. It is a powerful
  language which can do many things that surprise even experienced web
  developers. Learning this skill is definitely encouraged for every
  web developer.
</p>

<p>
  These tools are very strict about <strong>not</strong> mixing any
  style declarations in the JavaScript code. You would think that this
  is an obvious coding principle and should be taken for granted but
  it isn't. Taking a quick look at the list
  of <a href="http://plugins.jquery.com" class="external">jQuery
  plugins</a> reveals many tools that mix CSS into their code and hard
  code their style. Even if those styling variables are given as
  configuration variables, be it borders, images, colors, size or
  positioning, this leads to poor application design.
</p>

<p>
  A proper tool should only rely on CSS <em>class names</em> - because
  they offer a much more flexible styling environment. Let's take
  the <samp>tabs</samp> tool as an example. It offers a configuration
  variable called <samp>current</samp> representing a class name that
  is set to the currently active tab. Lets say you have set the value
  "active" as follows:
</p>

{% filter syntax('js') %}
  $("ul.tabs").tabs("div.panes > div", {current: 'active'});
{% endfilter %}

<p>
  After that you can style the current tab with CSS as follows:
</p>

{% filter syntax('css') %}
  ul.tabs .active {
  color: '#fff';
  fontWeight: bold;
  background-position:0 -40px;
  }
{% endfilter %}

<p>
  This means that you can have a whole CSS arsenal at your disposal
  while designing what the currently selected tab should look
  like. This kind of design principle is used throughout these
  tools. There are no hidden surprises in the tools related to
  styling. The tools are responsible for setting and removing classes
  from elements and after that all style is the responsibility of
  CSS. You can also customize all class names that these tools use.
</p>

<h3>Default CSS files</h3>

<p>
  For each tool we offer a default CSS file that you can use as the
  basis for your design. You can use the code, images and ideas from
  there for free. No obligations. They are fully documented and coded
  with good CSS practices. For example, you will never see this kind
  of statement:
</p>

{% filter syntax('css') %}
  /* define colors for body and p elements */
  body {
  color:#ccc;
  }

  p {
  color:#ccc;
  }
{% endfilter %}

<p>
  Instead it will always be shortened to:
</p>

{% filter syntax('css') %}
  body, p {
  color:#ccc;
  }
{% endfilter %}


<p>
  This was just a primitive example of good CSS practice, but it is
  used extensively in our CSS files.
</p>


<a name="graphics"></a>
<h2>Graphic design and presentation</h2>

<p>
  Since you are not tied to any specific HTML/CSS structures, you have
  lots of freedom in designing the look and feel of the tools. When
  designing the presentation of these tools or basically anything on
  the web, you have three important but different approaches to choose
  from. Now think of designing a rounded box for any content or a
  tooltip background for example. You have to choose one design
  pattern and stick with it. Here are the advantages and disadvantages
  of these choices:
</p>

<h3><em>1.</em> CSS-based design</h3>

<p>
  This approach depends primarily on CSS for the presentation. You'll
  use background colors, border colors and styling, web fonts and have
  only minimal use of graphics.
</p>


<ul>
  <li class="minus">
    <strong>limited visual control</strong>. There are lots of things
    you can tweak with CSS, but in the end they are limited and you
    simply cannot do everything with them.
  </li>
  <li class="plus">
    <strong>scalable size</strong>. Your elements can stretch
    horizontally and vertically without problems.
  </li>
  <li class="plus">
    <strong>maintenable</strong>. You can easily change the design
    just by editing a few lines of code.
  </li>
  <li class="plus">
    <strong>lightweight</strong>. CSS files are text which means that
    they can be downloaded much faster than images. CSS files can also
    be compressed and GZIPped which makes them even faster.
  </li>
</ul>

<p>
  There are lots of new features in the latest CSS version such as
  rounded borders, gradient borders, shadows and opacity, but these
  are not yet supported by every major browser. Some of the demos on
  this site uses these CSS3 features. If you are using
  Firefox&nbsp;3.5, Safari&nbsp;4.0 or other CSS3 compatible browser
  please take a look at the
  <a href="{{ content_url('demos/combine/scrollable-gallery-with-tooltips.html') }}">scrollable gallery with tooltips</a>
  demo and click on the thumbnails. You'll
  see nice looking drop shadows on the overlay. As you can see you can
  create stunning looks by only using CSS and the design will also be
  well-behaved in older browsers.
</p>


<h3><em>2.</em> Image-based design</h3>

<p>
  In this approach you'll typically use a single background image that
  is optimized for the purpose.
</p>

<ul>
  <li class="plus">
    <strong>Best visual control.</strong> Your design will look
    exactly how you want it to look. No compromises.
  </li>
  <li class="minus">
    <strong>Fixed size.</strong> Your elements' width and height is
    fixed. You have to optimize the content to fit inside elements and
    for excessive content you must rely on scripting or scrollbars.
  </li>
  <li class="minus">
    <strong>Heavy.</strong> More kilobytes to download and more
    requests to the server. Heavy use of images will slow down your
    pages.
  </li>
</ul>


<h3><em>3.</em> CSS <strong>and</strong> image-based design</h3>

<p>
  With this approach you'll use a lot of CSS tricks together with
  multiple background images.
</p>

<ul>
  <li class="plus">
    <strong>Best of both worlds.</strong> Scalable elements that look
    good.
  </li>
  <li class="minus">
    <strong>Lots of work.</strong> You must master CSS, and a tight
    integration with the graphics designer is needed. This approach
    requires more planning.
  </li>
</ul>

<p>
  jQuery Tools allows you to use any of above approaches and it does
  not restrict you to any hard-coded CSS coding or theming
  frameworks. Our demo area contains examples of all these approaches,
  but we mainly use the second approach. We typically use a single
  background image to demonstrate the tool in an appealing manner. We
  also offer you a lot of different general-use background images that
  you can use as the basis for your own design.
</p>

<a name="png24"></a>
<h3><strong>PNG-24 format</strong></h3>

<p>
  This website uses a lot of semi-transparent PNG-24 images which are
  not natively supported by IE6.
</p>

<div class="box petrol">
  jQuery Tools are <strong>proven</strong> to work with IE
  6.0+</strong> but this website does not optimize the visual
  experience for IE6 users.
</div>

<p>
  Because of this and many other huge limitations in IE6 all major
  players such as YouTube
  are <a href="http://www.techcrunch.com/2009/07/14/youtube-will-be-next-to-kiss-ie6-support-goodbye/"
  class="external">dropping the support for IE6</a>. Having said that
  we can get to the real point.
</p>

<p>
  When saving your web graphics, you should really consider using the
  PNG-24 file format. It has support for <a class="external"
  href="http://en.wikipedia.org/wiki/Alpha_compositing">alpha
  transparency</a>. This means that you can use any kind of opacity
  setting on your image. It's like working with Adobe Photoshop's
  layers. You can layer multiple PNG images on top of each other and
  there is lots of room for experimentation. Below you can see two
  images. The gray box is a PNG24 image with alpha transparency.
</p>


<p>
  <img src="{{ media_url('img/global/logo/eye.png') }}" border="0" />
  <img src="{{ media_url('img/tooltip/white_big.png') }}" border="0"
       style="margin-left:-150px"/>
</p>

<p>
  If you are not using IE6 you can see the eye <em>through</em> the
  PNG24 image. Many sites don't yet take full advantage of this
  wonderful graphics format.
</p>

<h4>Internet Explorer 6.0</h4>

<p>
  <strong>Alpha transparency is not natively supported by Internet
  Explorer 6.0</strong>. It is possible to make it work in IE6 by
  using the IE-proprietary AlphaImageLoader filter but, according to
  recent studies by Yahoo, this
  technology <a href="http://developer.yahoo.com/performance/rules.html#no_filters"
  class="external">should be avoided</a>. The problem with this filter
  is that it blocks rendering and freezes the browser while the image
  is being loaded; it increases memory consumption and is applied per
  element, not per image, so the problem is multiplied.
</p>

<p>
  You'll definitely get the most reliable results by using GIF or JPG
  images in place of PNG images on IE6. You can override this in your
  CSS as follows:
</p>

{% filter syntax('css') %}
  #myelement {
  background-image: url(corner.png);   /* all browsers */
  _background-image: url(corner.jpg);  /* IE6 only */
  }
{% endfilter %}

<p>
  The initial underscore is a hack that causes the CSS setting to be
  applied only to versions of IE older than 7. You may have the
  patience to do this, but I don't.
</p>

<h4>PNG24 and opacity in all versions of IE</h4>

<p>
  If you programmatically change the opacity of a PNG image in all
  versions of Internet Explorer it will cause ugly black borders
  around the image as seen in this screenshot:
</p>

<p>
  <img src="{{ media_url('img/png24-ie.png') }}" border="0" />
</p>

<p>
  This bug makes it impossible to make fading animations with PNG
  images in Internet Explorer. For this reason the Tooltip "slide"
  effect uses opacity fading in every browser other than in IE. This
  is the default behaviour but you can of course change this if your
  tooltip is not decorated with PNG graphics. Take a look at
  the <a href="{{ content_url('documentation/tooltip/index.html') }}">Tooltip front page</a> and
  look at the first demo in Firefox and then in IE. The tooltip fades
  in/out in Firefox but uses the sliding effect without opacity
  changes in IE.
</p>

<p>
  This "black box" bug can also happen in situations where a PNG image
  is placed on top of a transparent layer. I noticed this happening
  in <a href="{{
  content_url('demos/combine/scrollable-gallery-with-tooltips.html')
  }}">this demo</a>.
</p>


<a name="include"></a>
<h2><em>Including</em> the Tools</h2>

<p>
  The first thing you must do is include the tools on your pages. You
  can place the following statement on your page and you are ready to
  go:
</p>

{% filter syntax('html') %}
  {{ jqt.js }}
{% endfilter %}

<p>
  This will include the tools on your page with maximum
  performance. We are offering this high performance content delivery
  network (CDN) for free. You can use it in production
  environments. Enjoy!
</p>

<p>
  If you are using <a href="http://getfirebug.com/"
  class="external">Firebug</a> or similar JavaScript debugger you can
  easily test which tools are included and what are their versions by
  running the following command from the console:
</p>

{% filter syntax('js') %}
  console.dir($.tools);
{% endfilter %}

<p>
  You'll see following kind of result
</p>

<p style="margin:20px 0">
  <img src="{{ media_url('img/global-conf.gif') }}" alt="Global Configuration" />
</p>

<p>
  You can see each tool you have included and the version number.  If
  you drill down a little deeper into these global settings you will
  see each tool's default configuration values (a good source of
  "documentation"!) which are discussed more extensively in the
  important <a href="#global_configuration">global configuration</a>
  section.
</p>


<a name="initialize"></a>
<h2><em>Initializing</em> the Tools</h2>

<p>
  After the needed tools are included on the page, you need to
  initialize them. All tools follow the same pattern. Initialization
  always starts with a jQuery selector followed by the tool
  initialization function (constructor) and its configuration
  object. Here is an example using the <samp>scrollable</samp> tool:
</p>

{% filter syntax('js') %}
  // initialize tools.scrollable with configuration variables
  $("#wrap").scrollable({
  keyboard: false,
  circular: true
  });
{% endfilter %}


<p>
  This will make all elements scroll that are contained within an
  element whose <samp>id</samp> is "wrap". Next, comes a tool
  constructor named <samp>scrollable</samp> which takes a
  configuration object as an <em>argument</em>. This object defines
  the settings for how we want our elements to be scrolled. This
  example above illustrates the general way you will initialize all
  jQuery Tools.
</p>

<h3>Return value</h3>

<p>
  The constructor will always return the jQuery object that is a
  collection of the elements that are selected by the selector. This
  is how all proper jQuery plugins are recommended to behave. Again we
  use the <samp>scrollable</samp> tool as our example:
</p>

{% filter syntax('js') %}
  // return elements specified in the selector as a jQuery object
  var elements = $("div.scrollable").scrollable();

  /*
  now you can continue working with the jQuery object. you can,
  for example, add new plugins and use built-in jQuery constructs
  */
  elements.someOtherPlugin().onClick(function() {
  // do something when this element is clicked
  });
{% endfilter %}


<a name="global_configuration"></a>
<h2>Using global configurations</h2>

<p>
  Although you can change the default settings of the tools by
  supplying a configuration in the initialization phase you may be
  using the same configuration settings over and over again. In this
  case you may want to change the default configuration variables for
  the tools so that you don't need to specify the same setting every
  time. Here is an example of a global configuration setting:
</p>

{% filter syntax('js') %}
  // all overlays use the "apple" effect by default
  $.tools.overlay.conf.effect = "apple";
{% endfilter %}

<p>
  Afterwards you can simply do this:
</p>

{% filter syntax('js') %}
  // "apple" effect is now our default effect
  $("a[rel]").overlay();
{% endfilter %}

<p>
  Of course you can override these default settings just like before:
</p>

{% filter syntax('js') %}
  // override the global configuration setting
  $("a[rel]").overlay({effect: 'default'});
{% endfilter %}

<p>
  Every tool has a global configuration
  under <samp>$.tools.[TOOL_NAME].conf</samp>. For
  example <samp>$.tools.tabs.conf</samp>. You can change many global
  settings simultaneously by using jQuery
  built-in <samp>$.extend</samp> method as follows:
</p>

{% filter syntax('js') %}
  $.extend($.tools.overlay.conf, {
  effect: 'apple',
  speed: 1000
  });
{% endfilter %}

<p>
  The list of various configuration settings can be found on each
  individual tool's documentation page. One important thing about the
  global configuration is that it provides you a good source of
  "documentation". Try typing the following command into your Firebug
  console:
</p>

{% filter syntax('js') %}
  console.dir($.tools.overlay.conf);
{% endfilter %}

<p>
  And you should see the following information appear:
</p>

<p>
  <img src="{{ media_url('img/global-config2.gif') }}"
       title="Overlay configuration as seen from FireBug" />
</p>

<p>
  Here you can see the available configuration options and their
  default values. Very useful.
</p>


<a name="extending"></a>
<h2>Using jQuery Tools <em>plugins and effects</em></h2>

<p>
  jQuery Tools is the first framework to take full advantage of
  jQuery's powerful chaining technology. Here is an example of a
  chaining pattern:
</p>

{% filter syntax('js') %}
  // initialize a few scrollables and add more features to them
  $(".scroller").scrollable({circular: true}).
      navigator("#myNavi").autoscroll({interval: 4000});
{% endfilter %}

<p>
  You take one or more <samp>.scroller</samp> elements from a page and
  make them scrollable. The scrollable tool has only the absolute
  necessary features to make things scroll. If you want to have more
  features you can use <a href="#plugin">plugins</a>. In this example
  we used the <samp>navigator</samp> plugin to setup a navigator
  beside the scrollable. The <samp>autoscroll</samp> plugin makes the
  items scroll automatically without any user interaction.
</p>

<p>
  You can have multiple scrollables on the page and they can all be
  activated with this single line of code. All plugins may have their
  own set of configuration variables and they can also be set from
  the <a href="#global_configuration">global configuration</a>.
</p>

<p>
  Almost every tool has a few plugins that can be downloaded from
  the <a href="{{ content_url('download/index.html') }}">download page</a>.
  This kind of
  design pattern makes the overall file size dramatically smaller
  because you can only use the things you need. It also makes the code
  more organized and easier to understand. In the programming world
  this pattern is called
  a <a href="http://en.wikipedia.org/wiki/Decorator_pattern"
  class="external">decorator pattern</a> which is at the heart of
  jQuery: "take a bunch of elements from a page and do stuff with
  them". jQuery Tools takes this seriously and goes a step further
  than other libraries.
</p>

<p>
  Every tool has a built-in plugin architecture and you can
  easily <a href="#plugin">write your own plugins</a>.
</p>

<a name="effects"></a>
<h3>Effects</h3>

<p>
  Tabs, tooltip and overlay have a unique "effect framework" which
  enables you to change the default behaviour of each tool. Here is an
  example:
</p>

{% filter syntax('js') %}
  // use the "apple" effect for the overlays
  $("a[rel]").overlay({effect: 'apple'});
{% endfilter %}

<p>
  This configuration makes the overlay use an effect called "apple"
  which makes the overlay work as you may have seen on Apple's
  website. The purpose of the effects is to <em>change</em> the
  default behaviour whereas plugins <em>enrich</em> or add new
  features. In the case of the overlay the actual tool provides the
  basic functionality of overlaying such as initialization, keyboard
  and mouse interaction and document masking (with the mask tool)
  while the only job of the effect is to perform the opening and
  closing actions of the tool. This makes it fairly easy to implement
  different kind of effects. This design pattern makes the code more
  organized and makes the overall file size smaller just like the
  plugins.
<p>

<p>
  Some tools have many built-in effects and some have only one. You
  can also get more effects from
  the <a href="{{ content_url('download/index.html') }}">download page</a>.
  You can set
  the default effect in the <a href="#global_configuration">global
  configuration</a> so that you don't have to explicitly supply it to
  every initial configuration.
</p>

<h4>Writing your own effects</h4>

<p>
  Look at each individual tool's documentation for more information:
</p>

<ul>
  <li>
    <a href="{{ content_url('documentation/tabs/index.html') }}#effects">Writing effects for Tabs</a>
  </li>
  <li>
    <a href="{{ content_url('documentation/tooltip/index.html') }}#effects">Writing effects for Tooltip</a>
  </li>
  <li>
    <a href="{{ content_url('documentation/overlay/index.html') }}#effects">Writing effects for Overlay</a>
  </li>
  <li><a href="{{ content_url('documentation/validator/index.html') }}#effects">
      Writing effects for Validator
  </a></li>
</ul>

<p>
  <strong>Note:</strong> it is possible to define custom configuration
  variables for your effect by extending the global configuration. Say
  you have a custom overlay effect with the configuration
  property <samp>explosionSpeed</samp>; you can give it a default
  value as follows:
</p>

{% filter syntax('js') %}
  $.tools.overlay.conf.explosionSpeed = 500;
{% endfilter %}

<p>
  After that the users can either use the default value or override it
  from the overlay configuration.
</p>

{% endblock %}