Android开发之视频播放调用setVideoPath()方法

当setVideoPath()的时候，底层是这个走的：

setVideoPath()-->setVideoURI()-->openVideo()；

openVideo()只是setVideoURI()中的一部分，还有的没有写出来，下面看一下openVideo的具体内容：

private void openVideo() {
        if (mUri == null || mSurfaceHolder == null) {
            // not ready for playback just yet, will try again later
            return;
        }
        // we shouldn't clear the target state, because somebody might have
        // called start() previously
        release(false);

        AudioManager am = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
        am.requestAudioFocus(null, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);

        try {
            mMediaPlayer = new MediaPlayer();
            // TODO: create SubtitleController in MediaPlayer, but we need
            // a context for the subtitle renderers
            final Context context = getContext();
            final SubtitleController controller = new SubtitleController(
                    context, mMediaPlayer.getMediaTimeProvider(), mMediaPlayer);
            controller.registerRenderer(new WebVttRenderer(context));
            controller.registerRenderer(new TtmlRenderer(context));
            controller.registerRenderer(new Cea708CaptionRenderer(context));
            controller.registerRenderer(new ClosedCaptionRenderer(context));
            mMediaPlayer.setSubtitleAnchor(controller, this);

            if (mAudioSession != 0) {
                mMediaPlayer.setAudioSessionId(mAudioSession);
            } else {
                mAudioSession = mMediaPlayer.getAudioSessionId();
            }
            mMediaPlayer.setOnPreparedListener(mPreparedListener);
            mMediaPlayer.setOnVideoSizeChangedListener(mSizeChangedListener);
            mMediaPlayer.setOnCompletionListener(mCompletionListener);
            mMediaPlayer.setOnErrorListener(mErrorListener);
            mMediaPlayer.setOnInfoListener(mInfoListener);
            mMediaPlayer.setOnBufferingUpdateListener(mBufferingUpdateListener);
            mCurrentBufferPercentage = 0;
            mMediaPlayer.setDataSource(mContext, mUri, mHeaders);
            mMediaPlayer.setDisplay(mSurfaceHolder);
            mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
            mMediaPlayer.setScreenOnWhilePlaying(true);
            mMediaPlayer.prepareAsync();

            for (Pair<InputStream, MediaFormat> pending: mPendingSubtitleTracks) {
                try {
                    mMediaPlayer.addSubtitleSource(pending.first, pending.second);
                } catch (IllegalStateException e) {
                    mInfoListener.onInfo(
                            mMediaPlayer, MediaPlayer.MEDIA_INFO_UNSUPPORTED_SUBTITLE, 0);
                }
            }

            // we don't set the target state here either, but preserve the
            // target state that was there before.
            mCurrentState = STATE_PREPARING;
            attachMediaController();
        } catch (IOException ex) {
            Log.w(TAG, "Unable to open content: " + mUri, ex);
            mCurrentState = STATE_ERROR;
            mTargetState = STATE_ERROR;
            mErrorListener.onError(mMediaPlayer, MediaPlayer.MEDIA_ERROR_UNKNOWN, 0);
            return;
        } catch (IllegalArgumentException ex) {
            Log.w(TAG, "Unable to open content: " + mUri, ex);
            mCurrentState = STATE_ERROR;
            mTargetState = STATE_ERROR;
            mErrorListener.onError(mMediaPlayer, MediaPlayer.MEDIA_ERROR_UNKNOWN, 0);
            return;
        } finally {
            mPendingSubtitleTracks.clear();
        }
    }

从31行看，可以知道，执行setVideoPath()会重新执行VideoView的监听事件，会重新prepared等等。。。