swapper.js for cordova

swapper.js

/* Copyright (C) 2009-2020, Nick Galko. All rights reserved.
*
* This file is part of the Nick Galko source-code
* (https://galek.github.io/portfolio/).
*
* Your use and or redistribution of this software in source and / or
* binary form, with or without modification, is subject to: (i) your
* ongoing acceptance of and compliance with the terms and conditions of
* the Nick Galko License Agreement; and (ii) your inclusion of this notice
* in any version of this software that you use or redistribute.
* A copy of the NGTech License Agreement is available by contacting
* Nick Galko. at https://galek.github.io/portfolio/
*/

/**
 * Функция свайпа
 * @param {any} el
 * @param {any} callback
 */
function SwipeDetect(el, callback) {

    var touchsurface = el,
        swipedir,
        startX,
        startY,
        distX,
        distY,
        threshold = 150, //required min distance traveled to be considered swipe
        restraint = 100, // maximum distance allowed at the same time in perpendicular direction
        allowedTime = 300, // maximum time allowed to travel that distance
        elapsedTime,
        startTime,
        handleswipe = callback || function (swipedir) { }

    touchsurface.addEventListener('touchstart', function (e) {
        var touchobj = e.changedTouches[0]
        swipedir = 'none'
        dist = 0
        startX = touchobj.pageX
        startY = touchobj.pageY
        startTime = new Date().getTime() // record time when finger first makes contact with surface
        e.preventDefault()
    }, false)

    touchsurface.addEventListener('touchmove', function (e) {
        e.preventDefault() // prevent scrolling when inside DIV
    }, false)

    touchsurface.addEventListener('touchend', function (e) {
        var touchobj = e.changedTouches[0]
        distX = touchobj.pageX - startX // get horizontal dist traveled by finger while in contact with surface
        distY = touchobj.pageY - startY // get vertical dist traveled by finger while in contact with surface
        elapsedTime = new Date().getTime() - startTime // get time elapsed
        if (elapsedTime <= allowedTime) { // first condition for awipe met
            if (Math.abs(distX) >= threshold && Math.abs(distY) <= restraint) { // 2nd condition for horizontal swipe met
                swipedir = (distX < 0) ? 'left' : 'right' // if dist traveled is negative, it indicates left swipe
            }
            else if (Math.abs(distY) >= threshold && Math.abs(distX) <= restraint) { // 2nd condition for vertical swipe met
                swipedir = (distY < 0) ? 'up' : 'down' // if dist traveled is negative, it indicates up swipe
            }
        }
        handleswipe(swipedir)
        e.preventDefault()
    }, false)
}


/**USAGE**/
/*
function InitTouchSurface() {
    var el = document.getElementById('touchsurface');
    SwipeDetect(el, function (swipedir) {
        if (swipedir == 'left') {
            alert('You just swiped left!' + activatedNumber)
        }
        else if (swipedir == 'right') {
            alert('You just swiped right!' + act
        }
    })

*/