jquery.tap.js

;var jqt = function($, undefined) {
  var INVALIDATE_CLICKS_AFTER_TAP_THRESHOLD = 600;
  var incrementalElementId = 0;
  var mutex = 0;
  $.fn.tap = function(threshold, callback, touchOnly) {
    if (typeof threshold === 'function') {
      touchOnly = callback;
      callback = threshold;
      threshold = 15;
    }
    if ('ontouchstart' in window) {
      this.each(function() {
        var moveDistance = 0;
        var touch = null;
        var elementId = ++incrementalElementId;
        var startPoint = null
        var touching = false;
        var self = this;
        var $self = $(this);
        var invalidateClicksBefore = null;

        $self.click(function() {
          if (invalidateClicksBefore != null && Date.now() < invalidateClicksBefore) {
            return;
          } else {
            callback.apply(self, arguments);
          }
        });

        $self.bind('touchstart', function(e) {
          if (mutex != 0) return;
          else mutex = elementId;

          touching = true;
          moveDistance = 0;

          if (e.originalEvent.touches && e.originalEvent.touches[0]) {
            touch = e.originalEvent.touches[0];
            startPoint = { 
              x: touch.screenX, 
              y: touch.screenY,
              px: touch.pageX,
              py: touch.pageY,
              cx: touch.clientX,
              cy: touch.clientY
            }
          }
        });

        $self.bind('touchend', function(e) {
          if (mutex == elementId) mutex = 0;
          if (!touching) return;
          touching = false;
          if (moveDistance < threshold) {
            invalidateClicksBefore = Date.now() + INVALIDATE_CLICKS_AFTER_TAP_THRESHOLD;
            e.pageX = startPoint.px;
            e.pageY = startPoint.py;
            e.clientX = startPoint.cx;
            e.clientY = startPoint.cy;
            e.screenX = startPoint.x;
            e.scrrenY = startPoint.y;
            callback.apply(self, arguments);
          } else {
            $self.trigger('tap-failed');
          }
        });

        $self.bind('touchmove', function(e) {
          if (!touching) return;
          if (e.originalEvent.touches.length == 0 || startPoint === null) {
            return touching = false;
          }

          touch = e.originalEvent.touches[0];
          
          moveDistance = Math.sqrt(Math.pow(touch.screenX - startPoint.x, 2) +
                                   Math.pow(touch.screenY - startPoint.y, 2));

          if (moveDistance > threshold) {
            $self.trigger('exceed-tap-threshold');
            touching = false;
          }
        });

        $self.bind('touchcancel', function() {
          if (mutex == elementId) mutex = 0;
          touching = false;
          $self.trigger('tap-failed');
        })
      })
    } else if (!touchOnly) {
      this.click(callback);
    }
    return this;
  }
};
if (module && module.exports) {
  module.exports = function(jq) {
    return jqt(jq || window.jQuery || window.$)
  };
} else {
  jqt(window.jQuery || window.$)
}