MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

function nextHandler () {
curSong++;
//Enable previous button if we have at least one previous track
if (curSong > 0) {
mediaControl.addEventListener("previoustrackpressed", prevHandler);
}
if (curSong < playlist.length) {
//playlist[curSong] should already be loaded
playCurrent();
//Set up the next preload
var nextTrack = curSong + 1;
}
}
if (nextTrack < playlist.length) {
preload.src = playlist[nextTrack];
} else {
preload.src = null;
mediaControl.removeEventListener("nexttrackpressed", nextHandler);
}
function prevHandler() {
//If we're already playing the last song, add the next button handler again
if (curSong == playlist.length - 1) {
mediaControl.addEventListener("nexttrackpressed", nextHandler);
}
curSong--;
if (curSong == 0) {
mediaControl.removeEventListener("previoustrackpressed", prevHandler);
}
}
playCurrent();
preload.src = playlist[curSong + 1]; //This should always work
function playCurrent() {
audio1.src = playlist[curSong];
audio1.play();
mediaControl.trackName = "Segment " + (curSong + 1);
}
When playing sequential tracks like this from an app written in JavaScript and HTML, you might
notice brief gaps between the tracks, especially if the first track flows directly into the second. This is a
present limitation of the platform given the layers that exist between the HTML audio element and the
low-level XAudio2 APIs that are ultimately doing the real work. You can mitigate the effects to some
extent—for example, you can crossfade the two tracks or crossfade a third overlay track that contains a
little of the first and a little of the second track. You can also use a negative time offset to start playing
the next track slightly before the previous one ends. But if want you a truly seamless transition, you’ll
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