University of Natural Resources and Life Sciences (BOKU)
Institute of Computational Biology

JQueryMetadata

Homepage: https://github.com/MichaelDaum/jquery-metadata
Author(s): John Resig, Yehuda Katz, Joern Zaefferer, Paul McLanahan
Version: 2.1ef2bb44c86f5d0e98d55

This plugin is capable of extracting metadata from classes, random attributes, and child elements.

Usage

A lot of jQuery plugins are initialized and configured using metadata embeded into the markup thus eliminating the need to explicitly write JavaScript. A behavior is assigned to an html element by giving it the pertinent class name that the plugin listens to. Parameters to the plugin itself are embeded as a JSON object inside the class attribute. JQueryMetadata can also be encoded differently. Having it inside the class attribute as well is most common. One exception is JQueryCorner for example, that uses an explicit data-corner attribute, which of course isn't standard conform markup. However browsers happily ignore attributes that they don't understand. So that's not a problem in real live.

Examples

Load the plugin as required for the current page:

%JQREQUIRE{"mynewplugin"}%

This is how the markup looks like:

<div class="jqMyNewPlugin {key1:'value1', key2:'value2', key3:'value3'}">

<div>

This is the plugin's initializer reading the metadata:

jQuery(function($) {

  var defaults = {
    key1: 'default1',
    key2: 'default2',
    key3: 'default3'
  };

  // find all elements tagged .jqMyNewPlugin that aren't init'ed yet
  // ... using livequery instead of each to trigger initialisation of async content

  $(".jqMyNewPlugin:not(jqInitedMyNewPlugin)").livequery(function() {

     // create a jQuery object for this
     var $this = $(this);

     // prevent the markup to be init'ed multiple times
     $this.addClass("jqInitedMyNewPlugin");
   
     // get plugin options by merging defaults and current json objs
     var opts = $.extend({}, defaults, $this.metadata());

     // call the plugin handler
     $this.myNewPlugin(opts);
  });
});
24 Nov 2024 - 12:24 Foswiki v2.0.2