How to use jquery swipe without any library?

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天涯浪人
天涯浪人 2020-12-29 15:08

I need to create jQuery mobile like Swipe gestures $(\"#slider ul li div\").swipeleft(); using core jQuery without using any library or plugins not even jQuery

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  • 2020-12-29 15:38

    This is the code for touch swipe using javascript. Finally I found it hard by searching all over the internet. Thanks to padilicious.Below is the HTML code for slider.

    <div id="slider" ontouchstart="touchStart(event,'slider');" ontouchend="touchEnd(event);" 
    ontouchmove="touchMove(event);" ontouchcancel="touchCancel(event);">
    <ul id="slideul"><li><img src="1.jpg"></li><li>....</ul>
    </div>
    

    Below is the javascript code for the touch swipe. It's bit long. But it works for me. You don't have to change anything. Only place you have to change is processingRoutine() function. I've called 2 slide function i.e previous & next using this code sliders.goToNext() & sliders.goToPrev(). You can modify as you want..

    var triggerElementID = null; // this variable is used to identity the triggering element
    var fingerCount = 0;
    var startX = 0;
    var startY = 0;
    var curX = 0;
    var curY = 0;
    var deltaX = 0;
    var deltaY = 0;
    var horzDiff = 0;
    var vertDiff = 0;
    var minLength = 72; // the shortest distance the user may swipe
    var swipeLength = 0;
    var swipeAngle = null;
    var swipeDirection = null;
    
    // The 4 Touch Event Handlers
    
    // NOTE: the touchStart handler should also receive the ID of the triggering element
    // make sure its ID is passed in the event call placed in the element declaration, like:
    // <div id="picture-frame" ontouchstart="touchStart(event,'picture-frame');"  ontouchend="touchEnd(event);" ontouchmove="touchMove(event);" ontouchcancel="touchCancel(event);">
    
    function touchStart(event,passedName) {
        // disable the standard ability to select the touched object
        event.preventDefault();
        // get the total number of fingers touching the screen
        fingerCount = event.touches.length;
        // since we're looking for a swipe (single finger) and not a gesture (multiple fingers),
        // check that only one finger was used
        if ( fingerCount == 1 ) {
            // get the coordinates of the touch
            startX = event.touches[0].pageX;
            startY = event.touches[0].pageY;
            // store the triggering element ID
            triggerElementID = passedName;
        } else {
            // more than one finger touched so cancel
            touchCancel(event);
        }
    }
    
    function touchMove(event) {
        event.preventDefault();
        if ( event.touches.length == 1 ) {
            curX = event.touches[0].pageX;
            curY = event.touches[0].pageY;
        } else {
            touchCancel(event);
        }
    }
    
    function touchEnd(event) {
        event.preventDefault();
        // check to see if more than one finger was used and that there is an ending coordinate
        if ( fingerCount == 1 && curX != 0 ) {
            // use the Distance Formula to determine the length of the swipe
            swipeLength = Math.round(Math.sqrt(Math.pow(curX - startX,2) + Math.pow(curY - startY,2)));
            // if the user swiped more than the minimum length, perform the appropriate action
            if ( swipeLength >= minLength ) {
                caluculateAngle();
                determineSwipeDirection();
                processingRoutine();
                touchCancel(event); // reset the variables
            } else {
                touchCancel(event);
            }   
        } else {
            touchCancel(event);
        }
    }
    
    function touchCancel(event) {
        // reset the variables back to default values
        fingerCount = 0;
        startX = 0;
        startY = 0;
        curX = 0;
        curY = 0;
        deltaX = 0;
        deltaY = 0;
        horzDiff = 0;
        vertDiff = 0;
        swipeLength = 0;
        swipeAngle = null;
        swipeDirection = null;
        triggerElementID = null;
    }
    
    function caluculateAngle() {
        var X = startX-curX;
        var Y = curY-startY;
        var Z = Math.round(Math.sqrt(Math.pow(X,2)+Math.pow(Y,2))); //the distance - rounded - in pixels
        var r = Math.atan2(Y,X); //angle in radians (Cartesian system)
        swipeAngle = Math.round(r*180/Math.PI); //angle in degrees
        if ( swipeAngle < 0 ) { swipeAngle =  360 - Math.abs(swipeAngle); }
    }
    
    function determineSwipeDirection() {
    
        if ( (swipeAngle <= 45) && (swipeAngle >= 0) ) {
            swipeDirection = 'left';
        } else if ( (swipeAngle <= 360) && (swipeAngle >= 315) ) {
            swipeDirection = 'left';
        } else if ( (swipeAngle >= 135) && (swipeAngle <= 225) ) {
            swipeDirection = 'right';
        } else if ( (swipeAngle > 45) && (swipeAngle < 135) ) {
            swipeDirection = 'down';
        } else {
            swipeDirection = 'up';
        }
    }
    
    function processingRoutine() {
        var swipedElement = document.getElementById(triggerElementID);
        if ( swipeDirection == 'left' ) {
            sliders.goToNext();         
        } else if ( swipeDirection == 'right' ) {
            sliders.goToPrev();
        } else if ( swipeDirection == 'up' ) {
            sliders.goToPrev();         
        } else if ( swipeDirection == 'down' ) {
            sliders.goToNext();         
        }
    }
    
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