Question

I have written a plugin for jQuery which simulates mobile events, but with support for standard web browsers too. Here is the markup for the swipeleft and swiperight events:

(function($) {

    var settings = {
        swipe_h_threshold : 30,
        swipe_v_threshold : 50,
        taphold_threshold : 750,
        startevent        : ('ontouchstart' in document.documentElement) ? 'touchstart' : 'mousedown',
        endevent          : ('ontouchstart' in document.documentElement) ? 'touchend'   : 'mouseup'
    };
    // swipeleft Event:
    $.fn.swipeleft = function(handler) {
        return this.each(function() {

            $this = $(this);
            var start_x = 0;
            var end_x   = 0;

            $this.bind(settings.startevent, function(e) {
                e.stopPropagation();
                e.preventDefault();
                start_x = e.pageX;

                $this.one(settings.endevent, function(e) {
                    end_x = e.pageX;
                    if(start_x > end_x && (start_x - end_x >= settings.swipe_h_threshold))
                    {
                        handler.call(this);
                    }
                });
            });
        });
    };

    // swiperight Event:
    $.fn.swiperight = function(handler) {
        return this.each(function() {

            var $this = $(this);
            var start_x = 0;
            var end_x   = 0;

            $this.bind(settings.startevent, function(e) {
                e.preventDefault();
                e.stopPropagation();
                start_x = e.pageX;

                $this.one(settings.endevent, function(e) {
                    end_x = e.pageX;
                    if(start_x < end_x && (end_x - start_x >= settings.swipe_h_threshold))
                    {
                        handler.call(this);
                    }

                });
            });
        });
    };
}) (jQuery);

And I then call the events using the following:

$(‘#my_div’).swiperight(function() { self.nextCard(‘r’); });
$(‘#my_div’).swipeleft(function() { self.nextCard(‘r’); });

This seems to work fine on a desktop browser (well, Chrome anyway) > http://ben-major.co.uk/labs/carousel.html, but doesn’t seem to function in Mobile Safari. The swipeleft executes without problem, but swiperight won’t run whatsoever.

Can anyone offer any pointers?

Answer 1

If I’m not completely mistaken e (in the event callback) has an array touches on mobile browsers. It has one element for each touch event.

Here an example:

document.addEventListener('touchmove', function(event) {
    event.preventDefault();
    var touch = event.touches[0];
    console.log("Touch x:" + touch.pageX + ", y:" + touch.pageY);
}, false);