在触摸设备上清理HTML5视频

Question

如何优化擦洗触摸屏设备视频的过程？对于鼠标，使用mousedown mousemove事件，一切都可以成功进行。但是在iPad上无法进行擦洗。

var paused;

var shiftX;

progressBar.addEventListener('mousedown', startScrubbing);

function startScrubbing(e) {

    paused = video.paused;

    if (!paused) video.pause();

    shiftX = e.pageX - e.offsetX;

    scrubbing(e);

    document.addEventListener('mousemove', scrubbing);

    document.addEventListener('mouseup', stopScrubbing);

}

function scrubbing(e) {

    video.currentTime = ((e.pageX - shiftX) / progressBar.offsetWidth) * video.duration;

}

function stopScrubbing() {

    document.removeEventListener('mousemove', scrubbing);

    document.removeEventListener('mouseup', stopScrubbing);

    if (!paused) video.play();

}