工作需要筆記

/* element_id          物件id
/* trigger_prev        上一張圖
/* trigger_next        下一張圖

/*Amy's swipe*/
function swipe(element_id, trigger_prev, trigger_next) {
    var top = 0;
    var offset = 0;
    var x_start = 0;
    var x_end = 0;
    var y_start = 0;
    var y_end = 0;
    document.getElementById(element_id).addEventListener('touchstart', function (e) {
        top = $(document).scrollTop();
        var touch = e.touches[0];
        x_start = touch.pageX;
        y_start = touch.pageY;
    }, false);
    document.getElementById(element_id).addEventListener('touchmove', function (e) {
        //e.preventDefault();
        var touch = e.touches[0];
        x_end = touch.pageX;
        y_end = touch.pageY;
    }, false);
    document.getElementById(element_id).addEventListener('touchend', function (e) {
        offset = Math.abs(y_start - y_end);
        if (offset < 30) {
            if ((x_start - x_end) > 60) {
                $(trigger_prev).trigger('click');
            }
            if ((x_end - x_start) > 60) {
                $(trigger_next).trigger('click');
            }
        }
    }, false);
}