js swipe doesn't work on smartphones

Question

I've written simple swipe functionality on js.

On desktop works fine everything, but on smartphones it doesn't work.

Here is my Javascript:

(function(){
    var project = {
        dragging: false,
        xCordinateDown: null,
        yCordinateDown: null,
        init:function(){
            var swipeObject = document.getElementById('slide');
            swipeObject.addEventListener('mousedown', this.taped);
            swipeObject.addEventListener('mouseup', this.tapedOut);
            swipeObject.addEventListener('mouseleave', this.tapedOut);
            swipeObject.addEventListener('mousemove', this.swiped);
        },
        taped:function(e){
            this.dragging = true;
            this.xCordinateDown = e.clientX;
            this.yCordinateDown = e.clientY;
        },
        tapedOut:function(){
            this.dragging = false;
            this.xCordinateDown = null;
            this.yCordinateDown = null;
            document.getElementById("slide").style.top = 0;
        },
        swiped:function(e){
            if(this.dragging){
                var xCordinate = e.clientX;
                var yCordinate = e.clientY;

                var xDifference = this.xCordinateDown - xCordinate;
                var yDifference = this.yCordinateDown - yCordinate;

                if(Math.abs(xDifference) < Math.abs(yDifference)){
                    if(yDifference < 0){

                        document.getElementById("slide").style.top = Math.abs(yDifference) + 'px';
                    }                     
                }
            }
        }
    }
    project.init();
})();

How can I fix it on smartphones? Where is the problem?

here is jsfiddle: DEMO FIDDLE

thanks in advance

score 1 · Accepted Answer · answered Mar 04 '15 at 10:59

Use dedicated touch events: touchstart, touchmove, thouchend. You have to know that you will have to read the offset from TouchEvent.targetTouches:

var startCoords = null;
el.addEventListener('touchstart', function(event) {
    startCoords = [
        event.targetTouches[0].pageX,
        event.targetTouches[0].pageY,
    ];
});

And that the touchend event wont supply you with targetTouches.

I did an answer on whats the difference on touchstart/mousedown & touchend/mouseup is.

js swipe doesn't work on smartphones

1 Answers1