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Yahoo! UI Library

YAHOO Global  2.5.0

Yahoo! UI Library > yahoo > Env.js (source view)

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/**
 * YAHOO.env is used to keep track of what is known about the YUI library and
 * the browsing environment
 * @class YAHOO.env
 * @static
 */
YAHOO.env = YAHOO.env || {

    /**
     * Keeps the version info for all YUI modules that have reported themselves
     * @property modules
     * @type Object[]
     */
    modules: [],
    
    /**
     * List of functions that should be executed every time a YUI module
     * reports itself.
     * @property listeners
     * @type Function[]
     */
    listeners: []
};

/**
 * Returns the version data for the specified module:
 *      <dl>
 *      <dt>name:</dt>      <dd>The name of the module</dd>
 *      <dt>version:</dt>   <dd>The version in use</dd>
 *      <dt>build:</dt>     <dd>The build number in use</dd>
 *      <dt>versions:</dt>  <dd>All versions that were registered</dd>
 *      <dt>builds:</dt>    <dd>All builds that were registered.</dd>
 *      <dt>mainClass:</dt> <dd>An object that was was stamped with the
 *                 current version and build. If 
 *                 mainClass.VERSION != version or mainClass.BUILD != build,
 *                 multiple versions of pieces of the library have been
 *                 loaded, potentially causing issues.</dd>
 *       </dl>
 *
 * @method getVersion
 * @static
 * @param {String}  name the name of the module (event, slider, etc)
 * @return {Object} The version info
 */
YAHOO.env.getVersion = function(name) {
    return YAHOO.env.modules[name] || null;
};

/**
 * Do not fork for a browser if it can be avoided.  Use feature detection when
 * you can.  Use the user agent as a last resort.  YAHOO.env.ua stores a version
 * number for the browser engine, 0 otherwise.  This value may or may not map
 * to the version number of the browser using the engine.  The value is 
 * presented as a float so that it can easily be used for boolean evaluation 
 * as well as for looking for a particular range of versions.  Because of this, 
 * some of the granularity of the version info may be lost (e.g., Gecko 1.8.0.9 
 * reports 1.8).
 * @class YAHOO.env.ua
 * @static
 */
YAHOO.env.ua = function() {
    var o={

        /**
         * Internet Explorer version number or 0.  Example: 6
         * @property ie
         * @type float
         */
        ie:0,

        /**
         * Opera version number or 0.  Example: 9.2
         * @property opera
         * @type float
         */
        opera:0,

        /**
         * Gecko engine revision number.  Will evaluate to 1 if Gecko 
         * is detected but the revision could not be found. Other browsers
         * will be 0.  Example: 1.8
         * <pre>
         * Firefox 1.0.0.4: 1.7.8   <-- Reports 1.7
         * Firefox 1.5.0.9: 1.8.0.9 <-- Reports 1.8
         * Firefox 2.0.0.3: 1.8.1.3 <-- Reports 1.8
         * Firefox 3 alpha: 1.9a4   <-- Reports 1.9
         * </pre>
         * @property gecko
         * @type float
         */
        gecko:0,

        /**
         * AppleWebKit version.  KHTML browsers that are not WebKit browsers 
         * will evaluate to 1, other browsers 0.  Example: 418.9.1
         * <pre>
         * Safari 1.3.2 (312.6): 312.8.1 <-- Reports 312.8 -- currently the 
         *                                   latest available for Mac OSX 10.3.
         * Safari 2.0.2:         416     <-- hasOwnProperty introduced
         * Safari 2.0.4:         418     <-- preventDefault fixed
         * Safari 2.0.4 (419.3): 418.9.1 <-- One version of Safari may run
         *                                   different versions of webkit
         * Safari 2.0.4 (419.3): 419     <-- Tiger installations that have been
         *                                   updated, but not updated
         *                                   to the latest patch.
         * Webkit 212 nightly:   522+    <-- Safari 3.0 precursor (with native SVG
         *                                   and many major issues fixed).
         * Safari 3.0.4 (523.12):523.12  <-- First Tiger release - automatic update
         *                                   from 2.x via the 10.4.11 OS patch
         * Webkit nightly 1/2008:525+    <-- Supports DOMContentLoaded event
         *                                   
         * </pre>
         * http://developer.apple.com/internet/safari/uamatrix.html
         * @property webkit
         * @type float
         */
        webkit:0,

        /**
         * The mobile property will be set to a string containing any relevant
         * user agent information when a modern mobile browser is detected.
         * Currently limited to Safari on the iPhone/iPod Touch, Nokia N-series
         * devices with the WebKit-based browser, and Opera Mini.  
         * @property mobile 
         * @type string
         */
        mobile: null 
    };

    var ua=navigator.userAgent, m;

    // Modern KHTML browsers should qualify as Safari X-Grade
    if ((/KHTML/).test(ua)) {
        o.webkit=1;
    }
    // Modern WebKit browsers are at least X-Grade
    m=ua.match(/AppleWebKit\/([^\s]*)/);
    if (m&&m[1]) {
        o.webkit=parseFloat(m[1]);

        // Mobile browser check
        if (/ Mobile\//.test(ua)) {
            o.mobile = "Apple"; // iPhone or iPod Touch
        } else {
            m=ua.match(/NokiaN[^\/]*/);
            if (m) {
                o.mobile = m[0]; // Nokia N-series, ex: NokiaN95
            }
        }

    }

    if (!o.webkit) { // not webkit
        // @todo check Opera/8.01 (J2ME/MIDP; Opera Mini/2.0.4509/1316; fi; U; ssr)
        m=ua.match(/Opera[\s\/]([^\s]*)/);
        if (m&&m[1]) {
            o.opera=parseFloat(m[1]);
            m=ua.match(/Opera Mini[^;]*/);
            if (m) {
                o.mobile = m[0]; // ex: Opera Mini/2.0.4509/1316
            }
        } else { // not opera or webkit
            m=ua.match(/MSIE\s([^;]*)/);
            if (m&&m[1]) {
                o.ie=parseFloat(m[1]);
            } else { // not opera, webkit, or ie
                m=ua.match(/Gecko\/([^\s]*)/);
                if (m) {
                    o.gecko=1; // Gecko detected, look for revision
                    m=ua.match(/rv:([^\s\)]*)/);
                    if (m&&m[1]) {
                        o.gecko=parseFloat(m[1]);
                    }
                }
            }
        }
    }
    
    return o;
}();

/*
 * Initializes the global by creating the default namespaces and applying
 * any new configuration information that is detected.  This is the setup
 * for env.
 * @method init
 * @static
 * @private
 */
(function() {
    YAHOO.namespace("util", "widget", "example");
    if ("undefined" !== typeof YAHOO_config) {
        var l=YAHOO_config.listener,ls=YAHOO.env.listeners,unique=true,i;
        if (l) {
            // if YAHOO is loaded multiple times we need to check to see if
            // this is a new config object.  If it is, add the new component
            // load listener to the stack
            for (i=0;i<ls.length;i=i+1) {
                if (ls[i]==l) {
                    unique=false;
                    break;
                }
            }
            if (unique) {
                ls.push(l);
            }
        }
    }
})();

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