jquery.event.drag.live-2.2.js

/*! 
 * jquery.event.drag.live - v 2.2
 * Copyright (c) 2010 Three Dub Media - http://threedubmedia.com
 * Open Source MIT License - http://threedubmedia.com/code/license
 */
// Created: 2010-06-07
// Updated: 2012-05-21
// REQUIRES: jquery 1.7.x, event.drag 2.2

;(function( $ ){
	
// local refs (increase compression)
var $event = $.event,
// ref the special event config
drag = $event.special.drag,
// old drag event add method
origadd = drag.add,
// old drag event teradown method
origteardown = drag.teardown;

// allow events to bubble for delegation
drag.noBubble = false;

// the namespace for internal live events
drag.livekey = "livedrag";

// new drop event add method
drag.add = function( obj ){ 
	// call the old method
	origadd.apply( this, arguments );
	// read the data
	var data = $.data( this, drag.datakey );
	// bind the live "draginit" delegator
	if ( !data.live && obj.selector ){
		data.live = true;
		$event.add( this, "draginit."+ drag.livekey, drag.delegate );
	}
};

// new drop event teardown method
drag.teardown = function(){ 
	// call the old method
	origteardown.apply( this, arguments );
	// read the data
	var data = $.data( this, drag.datakey ) || {};
	// bind the live "draginit" delegator
	if ( data.live ){
		// remove the "live" delegation
		$event.remove( this, "draginit."+ drag.livekey, drag.delegate );
		data.live = false;
	}
};

// identify potential delegate elements
drag.delegate = function( event ){
	// local refs
	var elems = [], target, 
	// element event structure
	events = $.data( this, "events" ) || {};
	// query live events
	$.each( events || [], function( key, arr ){
		// no event type matches
		if ( key.indexOf("drag") !== 0 )
			return;
		$.each( arr || [], function( i, obj ){
			// locate the element to delegate
			target = $( event.target ).closest( obj.selector, event.currentTarget )[0];
			// no element found
			if ( !target ) 
				return;
			// add an event handler
			$event.add( target, obj.origType+'.'+drag.livekey, obj.origHandler || obj.handler, obj.data );
			// remember new elements
			if ( $.inArray( target, elems ) < 0 )
				elems.push( target );		
		});
	});
	// if there are no elements, break
	if ( !elems.length ) 
		return false;
	// return the matched results, and clenup when complete		
	return $( elems ).bind("dragend."+ drag.livekey, function(){
		$event.remove( this, "."+ drag.livekey ); // cleanup delegation
	});
};
	
})( jQuery );