/** * @author Ryan Johnson <ryan@livepipe.net> * @copyright 2007 LivePipe LLC * @package Control.SelectMultiple * @license MIT * @url http://livepipe.net/projects/control_select_multiple/ * @version 1.0.0 */if(typeof(Control) == 'undefined')	var Control = {};Control.SelectMultiple = Class.create();Object.extend(Control.SelectMultiple.prototype,{	select: false,	container: false,	numberOfCheckedBoxes: 0,	checkboxes: [],	hasExtraOption: false,	initialize: function(select,container,options){		this.options = {			checkboxSelector: 'input[type=checkbox]',			nameSelector: 'span.name',			labelSeparator: ', ',			valueSeparator: ',',			afterChange: Prototype.emptyFunction,			overflowString: function(str){				return str.truncate();			},			overflowLength: 30		};		Object.extend(this.options,options || {});		this.select = $(select);		this.container =  $(container);		this.checkboxes = (typeof(this.options.checkboxSelector) == 'function')			? this.options.checkboxSelector.bind(this)()			: this.container.getElementsBySelector(this.options.checkboxSelector)		;		var value_was_set = false;		if(this.options.value){			value_was_set = true;			this.setValue(this.options.value);			delete this.options.value;		}		this.hasExtraOption = false;		this.checkboxes.each(function(checkbox){			checkbox.observe('click',this.checkboxOnClick.bind(this,checkbox));		}.bind(this));		this.select.observe('change',this.selectOnChange.bind(this));		this.countAndCheckCheckBoxes();		if(!value_was_set)			this.scanCheckBoxes();		this.notify('afterChange',this.select.options[this.select.options.selectedIndex].value);	},	countAndCheckCheckBoxes: function(){		this.numberOfCheckedBoxes = this.checkboxes.inject(0,function(number,checkbox){			checkbox.checked = (this.select.options[this.select.options.selectedIndex].value == checkbox.value);			if(checkbox.checked)				++number;			return number;		}.bind(this));	},	setValue: function(value_string){		this.numberOfCheckedBoxes = 0;		(value_string.split ? value_string.split(this.options.valueSeparator) : value_string).each(function(value){			this.checkboxes.each(function(checkbox){				if(checkbox.value == value){					++this.numberOfCheckedBoxes;					checkbox.checked = true;				}else					checkbox.checked = false;			}.bind(this));		}.bind(this));		this.scanCheckBoxes();	},	selectOnChange: function(){		this.removeExtraOption();		this.countAndCheckCheckBoxes();		this.notify('afterChange',this.select.options[this.select.options.selectedIndex].value);	},	checkboxOnClick: function(checkbox){		this.numberOfCheckedBoxes += (checkbox.checked) ? 1 : -1;		this.scanCheckBoxes();		this.notify('afterChange',this.select.options[this.select.options.selectedIndex].value);	},	scanCheckBoxes: function(){		switch(this.numberOfCheckedBoxes){			case 1:				this.checkboxes.each(function(checkbox){					if(checkbox.checked){						$A(this.select.options).each(function(option,i){							if(option.value == checkbox.value){								this.select.options.selectedIndex = i;								throw $break;							}						}.bind(this));						throw $break;					}				}.bind(this));			case 0:				this.removeExtraOption();				break;			default:				this.addExtraOption();				break;		};	},	getLabelForExtraOption: function(){		var label = (typeof(this.options.nameSelector) == 'function' 			? this.options.nameSelector.bind(this)()			: this.container.getElementsBySelector(this.options.nameSelector).inject([],function(labels,name_element,i){				if(this.checkboxes[i].checked)					labels.push(name_element.innerHTML);				return labels;			}.bind(this))		).join(this.options.labelSeparator);		return (label.length >= this.options.overflowLength && this.options.overflowLength > 0)			? (typeof(this.options.overflowString) == 'function' ? this.options.overflowString(label) : this.options.overflowString)			: label		;	},	getValueForExtraOption: function(){		return this.checkboxes.inject([],function(values,checkbox){			if(checkbox.checked)				values.push(checkbox.value);			return values;		}).join(this.options.valueSeparator);	},	addExtraOption: function(){		this.removeExtraOption();		this.hasExtraOption = true;		this.select.options[this.select.options.length] = new Option(this.getLabelForExtraOption(),this.getValueForExtraOption());		this.select.options.selectedIndex = this.select.options.length - 1;	},	removeExtraOption: function(){		if(this.hasExtraOption){			this.select.remove(this.select.options.length - 1);			this.hasExtraOption = false;		}	},	notify: function(event_name){		try{			if(this.options[event_name])				return [this.options[event_name].apply(this.options[event_name],$A(arguments).slice(1))];		}catch(e){			if(e != $break)				throw e;			else				return false;		}	}});if(typeof(Object.Event) != 'undefined')	Object.Event.extend(Control.SelectMultiple);