音视频开发—抖音GsyVideoPlayer视频底层分析使用

1,008 阅读8分钟

一.初始化分析

1.初始化主要是构造了一个StandardGSYVideoPlayer

2.设置全屏布局的容器

代码如下:

listVideoUtil = new ListVideoUtil(this);
listVideoUtil.setFullViewContainer(videoFullContainer);
​
​
​
public ListVideoUtil(Context context) {
    gsyVideoPlayer = new StandardGSYVideoPlayer(context);
    this.context = context;
}

StandardGSYVideoPlayer的初始化化主要是加载R.layout.video_layout_standard这个布局,并且实例化一些组件,为组件设置监听事件;

初始化组件包括:播放/暂停按钮,播放时长,总时长,播放进度条,返回按钮,全屏按钮和视频标题,

初始化组件不包括:用于显示视频的TextureView,这个TextureView是动态添加的,放在下片文章中讲述;

初始化内容比较简单;

思考以下几个问题:

1.视频窗口的大小和位置是如何匹配ListView的item大小和位置的?

2.视频播放画面是如何显示出来的?

3.视频播放的声音如何显示出来的?

通过代码分析;

 @Override
 public View getView(final int position, View convertView, ViewGroup parent) {
​
   ....
​
   ....
​
   listVideoUtil.addVideoPlayer(position, holder.imageView, TAG, holder.videoContainer, holder.playerBtn);
​
   holder.playerBtn.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        notifyDataSetChanged();
        //listVideoUtil.setLoop(true);
        listVideoUtil.setPlayPositionAndTag(position, TAG);
//        final String url = "https://tv.miguvideo.com/?from=singlemessage&isappinstalled=0#video/live/761358370/room201706301600304971_R1";
        //listVideoUtil.setCachePath(new File(FileUtils.getPath()));
        final String url = "http://baobab.wdjcdn.com/14564977406580.mp4";
        listVideoUtil.startPlay(url);
      }
    });
​
•    ........
​
   .......
​
}
​
listview的adapter的getview方法每次都会走一次listVideoUtil.addVideoPlayer(position, holder.imageView, TAG, holder.videoContainer, holder.playerBtn);
/**
   * 动态添加视频播放
   *
   * @param position 位置
   * @param imgView  封面
   * @param tag    TAG类型
   * @param container player的容器
   * @param playBtn  播放按键
   */
  public void addVideoPlayer(final int position, View imgView, String tag,
                ViewGroup container, View playBtn) {
    container.removeAllViews();
    if (isCurrentViewPlaying(position, tag)) {
      if (!isFull) {
        ViewGroup viewGroup = (ViewGroup) gsyVideoPlayer.getParent();
        if (viewGroup != null)
          viewGroup.removeAllViews();
        container.addView(gsyVideoPlayer);
        playBtn.setVisibility(View.INVISIBLE);
      }
    } else {
      playBtn.setVisibility(View.VISIBLE);
      container.removeAllViews();  //增加封面
      container.addView(imgView);
    }
  }

代码可以看出addVideoPlayer方法的意思是,如果当前的position等于listVideoUtil中获取到的position,videoContainer中就显示gsyVideoPlayer,否则显示视频封面;

点击播放按钮的作用:

1.向listVideoUtil中设置position,并通过notifyDataSetChanged方法使重新走getview(),重新走getview方法时,会重新进入addVideoPlayer方法判断;

至此第一个疑问已经解决:视频显示在哪个item就是这个position决定的;视频窗口的大小由videoContainer的大小决定;

2.执行代码listVideoUtil.startPlay(url);

下面开始分析startPlay(url)中做了哪些操作?

 /**
   * 开始播放
   *
   * @param url 播放的URL
   */
  public void startPlay(String url) {
​
•    if (isSmall()) {
•      smallVideoToNormal();//如果是小窗口,就转为正常窗口播放,这个问题后面再说
•    }
​
•    this.url = url;
​
•    gsyVideoPlayer.release();
​
•    gsyVideoPlayer.setLooping(isLoop);//视频是否循环播放
​
•    gsyVideoPlayer.setSpeed(speed);//视频播放速度
​
•    gsyVideoPlayer.setNeedShowWifiTip(needShowWifiTip);//非wifi环境下,显示流量提醒
​
•    gsyVideoPlayer.setNeedLockFull(needLockFull);//是否需要全屏锁屏
​
•    gsyVideoPlayer.setUp(url, true, cachePath, mapHeadData, objects);//设置边缓存边播放
​
•    //增加title
•    gsyVideoPlayer.getTitleTextView().setVisibility(View.GONE);
​
•    //设置返回键
•    gsyVideoPlayer.getBackButton().setVisibility(View.GONE);
​
•    //设置全屏按键功能
•    gsyVideoPlayer.getFullscreenButton().setOnClickListener(new View.OnClickListener() {
•      @Override
•      public void onClick(View v) {
•        resolveFullBtn();
•      }
•    });
​
•    gsyVideoPlayer.startPlayLogic();
  }
​

就是一些简单设置项,其中gsyVideoPlayer.setUp(url, true, cachePath, mapHeadData, objects);会把url改为全局的mUrl;

@Override
  public void startPlayLogic() {
    if (mStandardVideoAllCallBack != null) {
      Debuger.printfLog("onClickStartThumb");
      mStandardVideoAllCallBack.onClickStartThumb(mUrl, mObjects);
    }
    prepareVideo();
    startDismissControlViewTimer();
  }
   /**
   * 开始状态视频播放
   */
  protected void prepareVideo() {
    if (GSYVideoManager.instance().listener() != null) {
      GSYVideoManager.instance().listener().onCompletion();
    }
    GSYVideoManager.instance().setListener(this);
    GSYVideoManager.instance().setPlayTag(mPlayTag);
    GSYVideoManager.instance().setPlayPosition(mPlayPosition);
    addTextureView();//动态添加TextureView
    mAudioManager.requestAudioFocus(onAudioFocusChangeListener, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);//暂时获取音频焦点
    ((Activity) getContext()).getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);//保持屏幕常亮不灭屏
    GSYVideoManager.instance().prepare(mUrl, mMapHeadData, mLooping, mSpeed);
    setStateAndUi(CURRENT_STATE_PREPAREING);
  }

科普1,音频焦点分类:

AudioManager.AUDIOFOCUS_REQUEST_GRANTED------------永久获取音频焦点

AudioManager.AUDIOFOCUS_GAIN_TRANSIENT-------------暂时获取音频焦点,比如音乐后台播放,当前视频播放会抢夺音频焦点,视频播放完成,音乐自动播放;

AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK--------提示类型获取音频焦点,比如听音乐的时候来短信,音乐声音降低

​
  /**
   * 添加播放的view
   */
  protected void addTextureView() {
    if (mTextureViewContainer.getChildCount() > 0) {
      mTextureViewContainer.removeAllViews();
    }
    mTextureView = null;
    mTextureView = new GSYTextureView(getContext());
    mTextureView.setSurfaceTextureListener(this);
    mTextureView.setRotation(mRotate);
​
•    RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
•    layoutParams.addRule(RelativeLayout.CENTER_IN_PARENT);
•    mTextureViewContainer.addView(mTextureView, layoutParams);
  }

构造了一个TextureView,并添加到gsyVideoPlayer布局中。

TextureView设置了SurfaceTextureListener;

科普2:SurfaceTextureListener回调方法:

 1.onSurfaceTextureAvailable(SurfaceTexture arg0, int arg1, int arg2)-------------TextureView可用时调用
​
 2.onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height)
​
 3.onSurfaceTextureDestroyed(SurfaceTexture surface)------------TextureView销毁时调用
​
 4.onSurfaceTextureUpdated(SurfaceTexture surface)

回到代码:

  @Override
  public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
    mSurface = new Surface(surface);
    GSYVideoManager.instance().setDisplay(mSurface);
    //显示暂停切换显示的图片
    showPauseCover();
  }

意思是:在TextureView可以使用时,将surface交给GSYVideoManager,用于显示视频的画面,至此第二个问题已经解决,当然此时还没有开始播放视频, 真正播放视频是在

GSYVideoManager.instance().prepare(mUrl, mMapHeadData, mLooping, mSpeed)中,此处的mUrl就是上面保存的url;

public void prepare(final String url, final Map<String, String> mapHeadData, boolean loop, float speed) {
    if (TextUtils.isEmpty(url)) return;
    Message msg = new Message();
    msg.what = HANDLER_PREPARE;
    GSYModel fb = new GSYModel(url, mapHeadData, loop, speed);
    msg.obj = fb;
    mMediaHandler.sendMessage(msg);
}
public class MediaHandler extends Handler {
    public MediaHandler(Looper looper) {
        super(looper);
    }
​
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
            case HANDLER_PREPARE:
                initVideo(msg);
                break;
private void initVideo(Message msg) {
    try {
        currentVideoWidth = 0;
        currentVideoHeight = 0;
        mediaPlayer.release();
​
        if (videoType == GSYVideoType.IJKPLAYER) {
            initIJKPlayer(msg);
        } else if (videoType == GSYVideoType.IJKEXOPLAYER) {
            initEXOPlayer(msg);
        }
        setNeedMute(needMute);
        mediaPlayer.setOnCompletionListener(GSYVideoManager.this);
        mediaPlayer.setOnBufferingUpdateListener(GSYVideoManager.this);
        mediaPlayer.setScreenOnWhilePlaying(true);
        mediaPlayer.setOnPreparedListener(GSYVideoManager.this);
        mediaPlayer.setOnSeekCompleteListener(GSYVideoManager.this);
        mediaPlayer.setOnErrorListener(GSYVideoManager.this);
        mediaPlayer.setOnInfoListener(GSYVideoManager.this);
        mediaPlayer.setOnVideoSizeChangedListener(GSYVideoManager.this);
        mediaPlayer.prepareAsync();
​
    } catch (Exception e) {
        e.printStackTrace();
    }
}

根据videoType的类型,创建不同的播放器,initIJKPlayer(msg)或者initEXOPlayer(msg);

不管哪种播放器,msg中有视频播放的url,用于播放器播放视频使用;

最后调用mediaPlayer.prepareAsync()播放视频;

首先思考以下几个问题:

1.点击全屏按钮,视频是怎么填充整个屏幕的?(以及视频放大时的动画效果实现)

2.视频填充屏幕后,又是如何实现横屏的?

3.视频是如何做到,列表中的视频和放大后的视频,无缝衔接的?

依旧通过代码分析:

//设置全屏按键功能
gsyVideoPlayer.getFullscreenButton().setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        resolveFullBtn();
    }
});

全屏按钮由一个点击事件触发

public void resolveFullBtn() {
    if (fullViewContainer == null) {
        return;
    }
    if (!isFull) {
        resolveToFull();
    } else {
        resolveMaterialToNormal(gsyVideoPlayer);
    }
}

fullViewContain是在ListVideoUtil初始化的时候设置的,具体分析可以查看blog.csdn.net/qq_15631341…

代码的意思是:

如果当前不是全屏,走resolveToFull;

如果当前是全屏,走resolveMaterialToNormal;

我们先分析展示全屏的过程,

/**
 * 处理全屏逻辑
 */
private void resolveToFull() {
    systemUiVisibility = ((Activity) context).getWindow().getDecorView().getSystemUiVisibility();
    CommonUtil.hideSupportActionBar(context, hideActionBar, hideStatusBar);//根据需求隐藏actionbar和statusbar
    if (hideKey) {
        hideNavKey(context);
    }
    isFull = true;
    //将gsyVideoplayer从原来的容器中剥离,即gsyVideoPlayer不在显示在ListView的摸一个item上了
   ViewGroup viewGroup = (ViewGroup) gsyVideoPlayer.getParent();
    //此处需要注意,gsyvideo还没有从listview的item上移除时,保存了当前的布局信息,用于后面动画的展示
listParams = gsyVideoPlayer.getLayoutParams(); if (viewGroup != null) { listParent = viewGroup; viewGroup.removeView(gsyVideoPlayer); }
 gsyVideoPlayer.setIfCurrentIsFullscreen(true); gsyVideoPlayer.getFullscreenButton().setImageResource(gsyVideoPlayer.getShrinkImageRes());//替换全屏按钮的图片为退出全屏的图片 gsyVideoPlayer.getBackButton().setVisibility(View.*VISIBLE*); //初始化旋转工具 orientationUtils = new OrientationUtils((Activity) context, gsyVideoPlayer); orientationUtils.setEnable(isAutoRotation()); gsyVideoPlayer.getBackButton().setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { resolveMaterialToNormal(gsyVideoPlayer);//设置退出全屏监听 } }); if (showFullAnimation) { if (fullViewContainer instanceof FrameLayout) {//目前只做了frameLoayout的判断 resolveMaterialAnimation(); } else { resolveFullAdd(); } } else { resolveFullAdd(); }} 如果设置的需要显示动画且当前的容器是FrameLayout就执行resolveMaterialAnimation();

否则执行resolveFullAdd()方法;即这两种方法的区别是一个是有动画效果的,一个是无动画效果的;

先来看一下没有动画效果的是如何实现的?

/**
 * 添加到全屏父布局里
 */
private void resolveFullAdd() {
    fullViewContainer.setBackgroundColor(Color.BLACK);
    fullViewContainer.addView(gsyVideoPlayer);
    resolveChangeFirstLogic(50);
}

就是把一开始设置的fullViewContain的背景改为黑色,再把gsyVideoPlayer的布局添加进来,最后执行resolveChangeFirstLogic(50)方法;

再来看一下有动画效果的是 如何实现的?

/**
 * 如果是5.0的动画开始位置
 */
private void resolveMaterialAnimation() {
    listItemRect = new int[2];
    listItemSize = new int[2];
    saveLocationStatus(context, hideStatusBar, hideActionBar);//保存gsyvideoplayer在listview的item中的位置和大小
    FrameLayout.LayoutParams lpParent = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
    FrameLayout frameLayout = new FrameLayout(context);
    frameLayout.setBackgroundColor(Color.BLACK);
    FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(listItemSize[0], listItemSize[1]);
    lp.setMargins(listItemRect[0], listItemRect[1], 0, 0);
    frameLayout.addView(gsyVideoPlayer, lp);
    fullViewContainer.addView(frameLayout, lpParent);
    handler.postDelayed(new Runnable() {
        @Override
        public void run() {
            //开始动画
            TransitionManager.beginDelayedTransition(fullViewContainer);
            resolveMaterialFullVideoShow(gsyVideoPlayer);
            resolveChangeFirstLogic(600);
        }
    }, 300);
}
/**
 * 保存大小和状态
 */
private void saveLocationStatus(Context context, boolean statusBar, boolean actionBar) {
    listParent.getLocationOnScreen(listItemRect);//获取listView中的gsyvideoplayer相对于屏幕的左边距和上边距并存入listItemRect中
    int statusBarH = getStatusBarHeight(context);
    int actionBerH = getActionBarHeight((Activity) context);
    if (statusBar) {
        listItemRect[1] = listItemRect[1] - statusBarH;
    }
    if (actionBar) {
        listItemRect[1] = listItemRect[1] - actionBerH;
    }
    listItemSize[0] = listParent.getWidth();
    listItemSize[1] = listParent.getHeight();
}

listParent是在resolveToFull中保存的gsyvideoplayer在listView的item中的布局参数;

上面的全屏动画在handler的post方法之前,先构造了左边这个布局,listItemRect标注反了,需要互换一下,不好意思,不会画图,将就一下,并把它加入到fullViewContain中;只不过因为demo中的左右边距都为0,所以listItemRect[0]就是0,listItemRect[1]就是上边距再加上statusbar和actionbar的高度

/**
 * 如果是5.0的,要从原位置过度到全屏位置
 */
private void resolveMaterialFullVideoShow(GSYBaseVideoPlayer gsyVideoPlayer) {
    FrameLayout.LayoutParams lp = (FrameLayout.LayoutParams) gsyVideoPlayer.getLayoutParams();
    lp.setMargins(0, 0, 0, 0);
    lp.height = ViewGroup.LayoutParams.MATCH_PARENT;
    lp.width = ViewGroup.LayoutParams.MATCH_PARENT;
    lp.gravity = Gravity.CENTER;
    gsyVideoPlayer.setLayoutParams(lp);
    gsyVideoPlayer.setIfCurrentIsFullscreen(true);
}

在resolveMaterialFullVideoShow方法执行后,变为右边那张图;

至于中间的动画效果:只要 TransitionManager.beginDelayedTransition(fullViewContainer);

科普1:

要改变某个控件的位置,可以用修改布局参数后setLayoutParams,如果想给这个过程加上动画效果,则可以在父节点上调用TransitionManager.beginDelayedTransition

无论是resolveToFull还是resolveMaterialToNormal至此已经完成了全屏变化;两个方法最后都调用了resolveChangeFirstLogic

/**
 * 是否全屏一开始马上自动横屏
 */
private void resolveChangeFirstLogic(int time) {
    if (isFullLandFrist()) {
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                if (orientationUtils.getIsLand() != 1) {
                    orientationUtils.resolveByClick();
                }
            }
        }, time);
    }
    gsyVideoPlayer.setIfCurrentIsFullscreen(true);
    if (videoAllCallBack != null) {
        Debuger.printfLog("onEnterFullscreen");
        videoAllCallBack.onEnterFullscreen(this.url);
    }
}

该方法是用来实现全屏后的屏幕旋转;

/**
 * 点击切换的逻辑,比如竖屏的时候点击了就是切换到横屏不会受屏幕的影响
 */
public void resolveByClick() {
    mClick = true;
    if (mIsLand == 0) {
        screenType = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        gsyVideoPlayer.getFullscreenButton().setImageResource(gsyVideoPlayer.getShrinkImageRes());
        mIsLand = 1;
        mClickLand = false;
    } else {
        screenType = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        if (gsyVideoPlayer.isIfCurrentIsFullscreen()) {
            gsyVideoPlayer.getFullscreenButton().setImageResource(gsyVideoPlayer.getShrinkImageRes());
        } else {
            gsyVideoPlayer.getFullscreenButton().setImageResource(gsyVideoPlayer.getEnlargeImageRes());
        }
        mIsLand = 0;
        mClickPort = false;
    }
​
}

这一块代码病史很难,就是横屏设置Activity为竖屏,竖屏就设置Activity为横屏;以上就是音视频中抖音GsyVideoPlayer视频播放的分析学习了,关于更多的音视频开发学习可以参考传送直达↓↓↓ :link.juejin.cn/?target=htt…要知道关于音视频的开发需要积累许多底层知识,需要一系列的学习途径才能成为一个音视频开发高手。这个文档里面记录了几千个音视频开发小知识。需要可以前往查看。

文末

最后解释一下,从列表视频到全屏视频的过程中,无缝衔接了,原因就是,只是GsyVideoPlayer这个布局换了一个父控件,GsyVideoManager中的medieplayer并没有停止播放,所以视频无缝衔接了。