3.7 release

MeidaPlayer 对应 jni 中的 android_media_MediaPlayer_release 方法：

static void
android_media_MediaPlayer_release(JNIEnv *env, jobject thiz)
{
  ALOGV("release");
  decVideoSurfaceRef(env, thiz);
  sp<MediaPlayer> mp = setMediaPlayer(env, thiz, 0);
  if (mp != NULL) {
    // this prevents native callbacks after the object is released
    mp->setListener(0);
    mp->disconnect();
  }
}

setListener 注释中说的很明白了，就是把 listener 置空。diconnect 这里是断开了了和 mediaserver 的连接。

void MediaPlayer::disconnect()
{
  ALOGV("disconnect");
  sp<IMediaPlayer> p;
  {
    Mutex::Autolock _l(mLock);
    p = mPlayer;
    mPlayer.clear();
  }
  if (p != 0) {
    p->disconnect();
  }
}