Easily support tap events without modifying your click event handlers

tap.js

/*global define: false, window: false */
define(['jquery'], function ($) {
	'use strict';

	return function () {
		/* Begin monkey-patch Tap event support into $ */
		var x = 0,
			y = 0,
			threshold = 40,
			// Sometimes there is lag between the last update and touchend.
			// Unfortunately, we can't get coords on touchend, so this is
			// the fudge factor.

			indexOfTap = function(x, y) {
				var i, len, tapX, tapY;
				for(i = 0, len = taps.length; i < len; i++) {
					tapX = taps[i][0];
					tapY = taps[i][1];
					if (Math.abs(tapX - x) <= threshold &&
						Math.abs(tapY - y) <= threshold) {
						return i;
					}
				}
				return -1;
			},
			makeTap = function (callback) {
				return function (e) {
					return callback.call(this, e);
				};
			},
			wrapClick = function (callback) {
				return function (e) {

					var tap = indexOfTap(e.x, e.y);
					if (tap !== -1) {
						taps.splice(tap, 1); // remove the tap
						e.preventDefault();
						e.stopPropagation();
						return;
					}

					return callback.call(this, e);
				};
			};

			var taps = [];


		try {
			var update = function (e) {
				x = e.touches[0].clientX;
				y = e.touches[0].clientY;
			};
			window.addEventListener('touchstart', update, true);
			window.addEventListener('touchmove', update, true);
			window.addEventListener('touchend', function (e) {
				taps.push([x,y]);
			}, true);

		} catch (o_O){
			//could not register listeners
		}

		$.fn.oldBind = $.fn.bind;
		$.fn.oldDelegate = $.fn.delegate;
		$.fn.bind = function (event, callback) {
			if (event.indexOf('click') > -1) {
				this.oldBind('tap', makeTap(callback));
				this.oldBind(event, wrapClick(callback));
			} else {
				this.oldBind(event, callback);
			}

			return this;
		};

		$.fn.delegate = function (selector, event, callback) {
			if (event.indexOf('click') > -1) {
				this.oldDelegate(selector, 'tap', makeTap(callback));
				this.oldDelegate(selector, event, wrapClick(callback));
			} else {
				this.oldDelegate(selector, event, callback);
			}

			return this;
		};

		/* end monkey-patch Tap event support into $  */
	};

});