【Android多媒体】NuPlayer for HTTP Live Streaming【3】

2. setVideoSurfaceTexture

display设置这里用了SurfaceTexture，可以说替换了以前的SurfaceView。SurfaceTexture比SurfaceView更优化和强大，主要是体现在现实窗口的绘画和控制方面，这方面以后再详细研究。
mediaplayer.cpp

status_t MediaPlayer::setVideoSurfaceTexture(
        const sp<IGraphicBufferProducer>& bufferProducer)
{
    ALOGV("setVideoSurfaceTexture");
    Mutex::Autolock _l(mLock);
    if (mPlayer == 0) return NO_INIT;
    return mPlayer->setVideoSurfaceTexture(bufferProducer);
}

NuPlayer.cpp

void NuPlayer::setVideoSurfaceTextureAsync(
        const sp<IGraphicBufferProducer> &bufferProducer) {
    sp<AMessage> msg = new AMessage(kWhatSetVideoNativeWindow, id());

    if (bufferProducer == NULL) {
        msg->setObject("native-window", NULL);
    } else {
        msg->setObject(
                "native-window",
                new NativeWindowWrapper(
                    new Surface(bufferProducer, true /* controlledByApp */)));
    }

    msg->post();
}

onMessageReceived处理：

        case kWhatSetVideoNativeWindow:
        {
            ALOGV("kWhatSetVideoNativeWindow");

            mDeferredActions.push_back(
                    new ShutdownDecoderAction(
                        false /* audio */, true /* video */));

            sp<RefBase> obj;
            CHECK(msg->findObject("native-window", &obj));

            mDeferredActions.push_back(
                    new SetSurfaceAction(
                        static_cast<NativeWindowWrapper *>(obj.get())));

            if (obj != NULL) {
                if (mStarted && mSource->getFormat(false /* audio */) != NULL) {
                    // Issue a seek to refresh the video screen only if started otherwise
                    // the extractor may not yet be started and will assert.
                    // If the video decoder is not set (perhaps audio only in this case)
                    // do not perform a seek as it is not needed.
                    int64_t currentPositionUs = 0;
                    if (getCurrentPosition(&currentPositionUs) == OK) {
                        mDeferredActions.push_back(
                                new SeekAction(currentPositionUs, false /* needNotify */));
                    }
                }

                // If there is a new surface texture, instantiate decoders
                // again if possible.
                mDeferredActions.push_back(
                        new SimpleAction(&NuPlayer::performScanSources));
            }

            processDeferredActions();
            break;
        }