foundation-sites/js/foundation.util.touch.js

//**************************************************
//**Work inspired by multiple jquery swipe plugins**
//**Done by Yohai Ararat ***************************
//**************************************************

import $ from 'jquery';

var Touch = {};

var startPosX,
    startPosY,
    startTime,
    elapsedTime,
    isMoving = false;

function onTouchEnd() {
  //  alert(this);
  this.removeEventListener('touchmove', onTouchMove);
  this.removeEventListener('touchend', onTouchEnd);
  isMoving = false;
}

function onTouchMove(e) {
  if ($.spotSwipe.preventDefault) { e.preventDefault(); }
  if(isMoving) {
    var x = e.touches[0].pageX;
    var y = e.touches[0].pageY;
    var dx = startPosX - x;
    var dy = startPosY - y;
    var dir;
    elapsedTime = new Date().getTime() - startTime;
    if(Math.abs(dx) >= $.spotSwipe.moveThreshold && elapsedTime <= $.spotSwipe.timeThreshold) {
      dir = dx > 0 ? 'left' : 'right';
    }
    // else if(Math.abs(dy) >= $.spotSwipe.moveThreshold && elapsedTime <= $.spotSwipe.timeThreshold) {
    //   dir = dy > 0 ? 'down' : 'up';
    // }
    if(dir) {
      e.preventDefault();
      onTouchEnd.call(this);
      $(this).trigger('swipe', dir).trigger(`swipe${dir}`);
    }
  }
}

function onTouchStart(e) {
  if (e.touches.length == 1) {
    startPosX = e.touches[0].pageX;
    startPosY = e.touches[0].pageY;
    isMoving = true;
    startTime = new Date().getTime();
    this.addEventListener('touchmove', onTouchMove, false);
    this.addEventListener('touchend', onTouchEnd, false);
  }
}

function init() {
  this.addEventListener && this.addEventListener('touchstart', onTouchStart, false);
}

function teardown() {
  this.removeEventListener('touchstart', onTouchStart);
}

class SpotSwipe {
  constructor($) {
    this.version = '1.0.0';
    this.enabled = 'ontouchstart' in document.documentElement;
    this.preventDefault = false;
    this.moveThreshold = 75;
    this.timeThreshold = 200;
    this.$ = $;
    this._init();
  }

  _init() {
    var $ = this.$;
    $.event.special.swipe = { setup: init };

    $.each(['left', 'up', 'down', 'right'], function () {
      $.event.special[`swipe${this}`] = { setup: function(){
        $(this).on('swipe', $.noop);
      } };
    });
  }
}

/****************************************************
 * As far as I can tell, both setupSpotSwipe and    *
 * setupTouchHandler should be idempotent,          *
 * because they directly replace functions &        *
 * values, and do not add event handlers directly.  *
 ****************************************************/

Touch.setupSpotSwipe = function($) {
  $.spotSwipe = new SpotSwipe($);
};

/****************************************************
 * Method for adding pseudo drag events to elements *
 ***************************************************/
Touch.setupTouchHandler = function($) {
  $.fn.addTouch = function(){
    this.each(function(i,el){
      $(el).bind('touchstart touchmove touchend touchcancel',function(){
        //we pass the original event object because the jQuery event
        //object is normalized to w3c specs and does not provide the TouchList
        handleTouch(event);
      });
    });

    var handleTouch = function(event){
      var touches = event.changedTouches,
          first = touches[0],
          eventTypes = {
            touchstart: 'mousedown',
            touchmove: 'mousemove',
            touchend: 'mouseup'
          },
          type = eventTypes[event.type],
          simulatedEvent
        ;

      if('MouseEvent' in window && typeof window.MouseEvent === 'function') {
        simulatedEvent = new window.MouseEvent(type, {
          'bubbles': true,
          'cancelable': true,
          'screenX': first.screenX,
          'screenY': first.screenY,
          'clientX': first.clientX,
          'clientY': first.clientY
        });
      } else {
        simulatedEvent = document.createEvent('MouseEvent');
        simulatedEvent.initMouseEvent(type, true, true, window, 1, first.screenX, first.screenY, first.clientX, first.clientY, false, false, false, false, 0/*left*/, null);
      }
      first.target.dispatchEvent(simulatedEvent);
    };
  };
};

Touch.init = function($) {
  if(typeof($.spotSwipe) === 'undefined') {
    Touch.setupSpotSwipe($);
    Touch.setupTouchHandler($);
  }
};

export {Touch};