jquery.placeholder.js

/**
 * Placeholder
 * @author Diego Oliveira <[email protected]>
 */
;(function(){
	var _private 	= {},
		methods 	= {};

	_private = {
		onblur 		: function(force){
			if (this.input.tagName.toLowerCase() === "input" && /(radio|checkbox|hidden)/gi.test(this.input.type)) return;

			if (!this.value || force) {
				$(this.input)
					.val(this.input.getAttribute("placeholder"))
					.addClass(this.klass);
			};
		},

		onfocus 	: function(){
			if (this.input.tagName.toLowerCase() === "input" && /(radio|checkbox|hidden)/gi.test(this.input.type)) return;

			if (this.value === this.input.getAttribute("placeholder")) {
				$(this.input)
					.val("")
					.removeClass(this.klass);
			};
		},

		settings 	: {
			klass 		: "placeholder",
			selector	: "input[placeholder], textarea[placeholder]"
		}
	};

	methods = {
		init 		: function(options){
			$.extend(_private.settings, options);

			$("body")
				.on({
					"blur.placeholder" 		: function(){
						_private.onblur.call({
							input 		: this,
							klass 		: _private.settings.klass,
							value 		: $.trim(this.value)
						});
					},
					"focus.placeholder" 	: function(){
						_private.onfocus.call({
							input 		: this,
							klass 		: _private.settings.klass,
							value 		: $.trim(this.value)
						});
					}
				}, _private.settings.selector)

				.on("submit.placeholder", "form", function(){
					var $placeholders = $(this).find(_private.settings.selector);

					$placeholders.length && $placeholders.each(function(){
						_private.onfocus.call({
							input 		: this,
							klass 		: _private.settings.klass,
							value 		: $.trim(this.value)
						});
					});
				});

			methods.update.call( $(_private.settings.selector) );
		},

		add 		: function(fields){
			$(fields).each(function(){
				_private.onblur.call({
					input 		: this,
					klass 		: _private.settings.klass,
					value 		: $.trim(this.value)
				});
			});
		},

		update 		: function(fields){
			$(fields ? fields : _private.settings.selector).each(function(){
				_private.onblur.call({
					input 		: this,
					klass 		: _private.settings.klass,
					value 		: $.trim(this.value)
				}, true);
			});
		}
	};

	$.placeholder = (function(support){
		if (support) {

			return function(){
				return this;
			};

		} else {

			return function(method){
				if (methods[method]) {
					return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
				} if (typeof method === "object" || !method) {
					return methods.init.apply(this, arguments);
				} else {
					$.error("Method " + method + " does not exist on jQuery.placeholder");
				};
			};

		};
	})( !!("placeholder" in document.createElement("input")) );
})()