自定义高性能播放器, 实现边下边播缓存等功能

VideoPlayerDemo

项目地址：Zhaoss/VideoPlayerDemo

简介：自定义高性能播放器, 实现边下边播缓存等功能

更多：作者提 Bug

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本项目使用播放器是ijkplay, 并且进行封装和修改

主要功能:
1.重新编辑 ijkplay 的 so 库, 使其更精简和支持 https 协议
2.自定义 MediaDataSource, 使用 okhttp 重写网络框架, 网络播放更流畅
3.实现视频缓存, 并且自定义 LRUCache 算法管理缓存文件
4.全局使用一个播放器, 实现视频在多个 Activity 之前无缝切换, 流畅播放
5.加入更多兼容性判断, 适配绝大数机型

①导入 ijkplay:

//需要的权限
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>首先将 lib 文件夹下的 so 库粘贴过来, (因为官方自带的 so 库是不支持 https 的, 我重新编译的这个 so 库支持 https 协议,
并且使用的是精简版的配置, 网上关于 ijkplay 编译的流程和配置挺多的, 可以根据自己的需求自定义)然后在 module 的 build 中加入 "implementation 'tv.danmaku.ijk.media:ijkplayer-java:0.8.8'"

②使用播放器的方法:

1.我封装了一个 MediaPlayerTool 工具类包含的初始化 so 库和一些回调等等

 //通过单例得到媒体播放工具mMediaPlayerTool = MediaPlayerTool.getInstance();//这里会自动初始化 so 库 有些手机会找不到 so, 会自动使用系统的播放器private MediaPlayerTool(){try {IjkMediaPlayer.loadLibrariesOnce(null);IjkMediaPlayer.native_profileBegin("libijkplayer.so");loadIjkSucc = true;}catch (UnsatisfiedLinkError e){e.printStackTrace();loadIjkSucc = false;}
}//一些生命周期回调
public static abstract class VideoListener {//视频开始播放public void onStart(){};//视频被停止播放public void onStop(){};//视频播放完成public void onCompletion(){};//视频旋转角度参数初始化完成public void onRotationInfo(int rotation){};//播放进度 0-1public void onPlayProgress(long currentPosition){};//缓存速度 1-100public void onBufferProgress(int progress){};}

2.因为我使用的是 RecyclerView,所以先找到当前屏幕中处于可以播放范围的 item

    //首先循环 RecyclerView 中所有 itemView, 找到在屏幕可见范围内的 itemprivate void checkPlayVideo(){currentPlayIndex = 0;videoPositionList.clear();int childCount = rv_video.getChildCount();for (int x = 0; x < childCount; x++) {View childView = rv_video.getChildAt(x);//isPlayRange()这个方法很重要boolean playRange = isPlayRange(childView.findViewById(R.id.rl_video), rv_video);if(playRange){int position = rv_video.getChildAdapterPosition(childView);if(position>=0 && !videoPositionList.contains(position)){videoPositionList.add(position);}}}}//检查当前 item 是否在 RecyclerView 可见的范围内private boolean isPlayRange(View childView, View parentView){if(childView==null || parentView==null){return false;}int[] childLocal = new int[2];childView.getLocationOnScreen(childLocal);int[] parentLocal = new int[2];parentView.getLocationOnScreen(parentLocal);boolean playRange = childLocal[1]>=parentLocal[1] &&childLocal[1]<=parentLocal[1]+parentView.getHeight()-childView.getHeight();return playRange;}

3.我还封装了一个 TextureView, 里面包含一些初始化 SurfaceTexture 和视频裁剪播放的方法

    //视频居中播放private void setVideoCenter(float viewWidth, float viewHeight, float videoWidth, float videoHeight){Matrix matrix = new Matrix();float sx = viewWidth/videoWidth;float sy = viewHeight/videoHeight;float maxScale = Math.max(sx, sy);matrix.preTranslate((viewWidth - videoWidth) / 2, (viewHeight - videoHeight) / 2);matrix.preScale(videoWidth/viewWidth, videoHeight/viewHeight);matrix.postScale(maxScale, maxScale, viewWidth/2, viewHeight/2);mTextureView.setTransform(matrix);mTextureView.postInvalidate();}//初始化 SurfaceTexturepublic SurfaceTexture newSurfaceTexture(){int[] textures = new int[1];GLES20.glGenTextures(1, textures, 0);int texName = textures[0];SurfaceTexture surfaceTexture = new SurfaceTexture(texName);surfaceTexture.detachFromGLContext();return surfaceTexture;}

4.接下来就是播放代码了

private void playVideoByPosition(int position){//根据传进来的 position 找到对应的 ViewHolderfinal MainAdapter.MyViewHolder vh = (MainAdapter.MyViewHolder)       rv_video.findViewHolderForAdapterPosition(position);if(vh == null){return ;}currentPlayView = vh.rl_video;//初始化一些播放状态, 如进度条,播放按钮,加载框等//显示正在加载的界面vh.iv_play_icon.setVisibility(View.GONE);vh.pb_video.setVisibility(View.VISIBLE);vh.iv_cover.setVisibility(View.VISIBLE);vh.tv_play_time.setText("");//初始化播放器mMediaPlayerTool.initMediaPLayer();mMediaPlayerTool.setVolume(0);//设置视频 urlString videoUrl = dataList.get(position).getVideoUrl();mMediaPlayerTool.setDataSource(videoUrl);myVideoListener = new MediaPlayerTool.VideoListener() {@Overridepublic void onStart() {//将播放图标和封面隐藏vh.iv_play_icon.setVisibility(View.GONE);vh.pb_video.setVisibility(View.GONE);//防止闪屏vh.iv_cover.postDelayed(new Runnable() {@Overridepublic void run() {vh.iv_cover.setVisibility(View.GONE);}}, 300);}@Overridepublic void onStop() {//播放停止vh.pb_video.setVisibility(View.GONE);vh.iv_cover.setVisibility(View.VISIBLE);vh.iv_play_icon.setVisibility(View.VISIBLE);vh.tv_play_time.setText("");currentPlayView = null;}@Overridepublic void onCompletion() {//播放下一个currentPlayIndex++;playVideoByPosition(-1);}@Overridepublic void onRotationInfo(int rotation) {//设置旋转播放vh.playTextureView.setRotation(rotation);}@Overridepublic void onPlayProgress(long currentPosition) {//显示播放时长String date = MyUtil.fromMMss(mMediaPlayerTool.getDuration() - currentPosition);vh.tv_play_time.setText(date);}};mMediaPlayerTool.setVideoListener(myVideoListener);//这里重置一下 TextureViewvh.playTextureView.resetTextureView();mMediaPlayerTool.setPlayTextureView(vh.playTextureView);mMediaPlayerTool.setSurfaceTexture(vh.playTextureView.getSurfaceTexture());//准备播放mMediaPlayerTool.prepare();}

③重写 MediaDataSource, 使用 okhttp 实现边下边播和视频缓存

1.一共需要重写 3 个方法 getSize(),close()和 readAt(); 先说 getSize()

    public long getSize() throws IOException {//开始播放时, 播放器会调用一下 getSize()来初始化视频大小, 这时我们就要初始化一条视频播放流if(networkInPutStream == null) {initInputStream();}return contentLength;}//初始化一个视频流出来, 可能是本地或网络private void initInputStream() throws IOException{File file = checkCache(mMd5);if(file != null){//更新一下缓存文件VideoLRUCacheUtil.updateVideoCacheBean(mMd5, file.getAbsolutePath(), file.length());//读取的本地缓存文件isCacheVideo = true;localVideoFile = file;//开启一个本地视频流localStream = new RandomAccessFile(localVideoFile, "rw");contentLength = file.length();}else {//没有缓存 开启一个网络流, 并且开启一个缓存流, 实现视频缓存isCacheVideo = false;//开启一个网络视频流networkInPutStream = openHttpClient(0);//要写入的本地缓存文件localVideoFile = VideoLRUCacheUtil.createCacheFile(MyApplication.mContext, mMd5, contentLength);//要写入的本地缓存视频流localStream = new RandomAccessFile(localVideoFile, "rw");}}

2.然后是 readAt()方法, 也是最重要的一个方法

    /*** @param position 视频流读取进度* @param buffer 要把读取到的数据存到这个数组* @param offset 数据开始写入的坐标* @param size 本次一共读取数据的大小* @throws IOException*///记录当前读取流的索引long mPosition = 0;@Overridepublic int readAt(long position, byte[] buffer, int offset, int size) throws IOException {if(position>=contentLength || localStream==null){return -1;}//是否将此字节缓存到本地boolean isWriteVideo = syncInputStream(position);//读取的流的长度不能大于 contentLengthif (position+size > contentLength) {size -= position+size-contentLength;}//读取指定大小的视频数据byte[] bytes;if(isCacheVideo){//从本地读取bytes = readByteBySize(localStream, size);}else{//从网络读取bytes = readByteBySize(networkInPutStream, size);}if(bytes != null) {//写入到播放器的数组中System.arraycopy(bytes, 0, buffer, offset, size);if (isWriteVideo && !isCacheVideo) {//将视频缓存到本地localStream.write(bytes);}//记录数据流读取到哪步了mPosition += size;}return size;}/*** 从 inputStream 里读取 size 大小的数据*/private byte[] readByteBySize(InputStream inputStream, int size) throws IOException{ByteArrayOutputStream out = new ByteArrayOutputStream();byte[] buf = new byte[size];int len;while ((len = inputStream.read(buf)) != -1) {out.write(buf, 0, len);if (out.size() == size) {return out.toByteArray();} else {buf = new byte[size - out.size()];}}return null;}/*** 删除 file 一部分字节, 从 position 到 file.size*/private void deleteFileByPosition(long position) throws IOException{FileInputStream in = new FileInputStream(localVideoFile);File tempFile = VideoLRUCacheUtil.createTempFile(MyApplication.mContext);FileOutputStream out = new FileOutputStream(tempFile);byte[] buf = new byte[8192];int len;while ((len = in.read(buf)) != -1) {if(position <= len){out.write(buf, 0, (int) position);out.close();in.close();localVideoFile.delete();tempFile.renameTo(localVideoFile);localStream = new RandomAccessFile(localVideoFile, "rw");return ;}else{position -= len;out.write(buf, 0, len);}}tempFile.delete();}

3.主要说一下 syncInputStream(), 因为有可能出现一种情况, 比如一个视频长度 100, 播放器首先读取视频的 1 到 10 之间的数据, 然后在读取 90 到 100 之间的数据, 然后在从 1 播放到 100; 所以这时我们需要同步视频流, 和播放进度保持一致这时就需要重新开启一个 IO 流(如果在读取本地缓存时可以直接使用 RandomAccessFile.seek()方法跳转)

 //同步数据流private boolean syncInputStream(long position) throws IOException{boolean isWriteVideo = true;//判断两次读取数据是否连续if(mPosition != position){if(isCacheVideo){//如果是本地缓存, 直接跳转到该索引localStream.seek(position);}else{if(mPosition > position){//同步本地缓存流localStream.close();deleteFileByPosition(position);localStream.seek(position);}else{isWriteVideo = false;}networkInPutStream.close();//重新开启一个网络流networkInPutStream = openHttpClient((int) position);}mPosition = position;}return isWriteVideo;}

4.最后一个是 close()方法, 主要播放停止后释放一些资源

public void close() throws IOException {if(networkInPutStream != null){networkInPutStream.close();networkInPutStream = null;}if(localStream != null){localStream.close();localStream = null;}if(localVideoFile.length()!=contentLength){localVideoFile.delete();}}

④视频缓存和 LRUCache 管理

1.首先创建缓存文件, 在刚才的 MediaDataSource.getSize()方法里有一句代码

localVideoFile = VideoLRUCacheUtil.createCacheFile(MyApplication.mContext, mMd5, contentLength);public static File createCacheFile(Context context, String md5, long fileSize){//创建一个视频缓存文件, 在 data/data 目录下File filesDir = context.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS);File cacheFile = new File(filesDir, md5);if(!cacheFile.exists()) {cacheFile.createNewFile();}//将缓存信息存到数据库VideoLRUCacheUtil.updateVideoCacheBean(md5, cacheFile.getAbsolutePath(), fileSize);return cacheFile;}

2.然后是读取缓存文件, 在刚才的 MediaDataSource.getSize()方法里还有一句代码

 //检查本地是否有缓存, 2 步确认, 数据库中是否存在, 本地文件是否存在private File checkCache(String md5){//查询数据库VideoCacheBean bean = VideoCacheDBUtil.query(md5);if(bean != null){File file = new File(bean.getVideoPath());if(file.exists()){return file;}}return null;}

3.LRUCache 的实现

//清理超过大小和存储时间的视频缓存文件
VideoLRUCacheUtil.checkCacheSize(mContext);public static void checkCacheSize(Context context){ArrayList<VideoCacheBean> videoCacheList = VideoCacheDBUtil.query();//检查一下数据库里面的缓存文件是否存在for (VideoCacheBean bean : videoCacheList){if(bean.getFileSize() == 0){File videoFile = new File(bean.getVideoPath());//如果文件不存在或者文件大小不匹配, 那么删除if(!videoFile.exists() && videoFile.length()!=bean.getFileSize()){VideoCacheDBUtil.delete(bean);}}}long currentSize = 0;long currentTime = System.currentTimeMillis();for (VideoCacheBean bean : videoCacheList){//太久远的文件删除if(currentTime-bean.getPlayTime() > maxCacheTime){VideoCacheDBUtil.delete(bean);}else {//大于存储空间的删除if (currentSize + bean.getFileSize() > maxDirSize) {VideoCacheDBUtil.delete(bean);} else {currentSize += bean.getFileSize();}}}//删除不符合规则的缓存deleteDirRoom(context.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS), VideoCacheDBUtil.query());}//更新缓存文件的播放次数和最后播放时间public static void updateVideoCacheBean(String md5, String videoPath, long fileSize){VideoCacheBean videoCacheBean = VideoCacheDBUtil.query(md5);if(videoCacheBean == null){videoCacheBean = new VideoCacheBean();videoCacheBean.setKey(md5);videoCacheBean.setVideoPath(videoPath);videoCacheBean.setFileSize(fileSize);}videoCacheBean.setPlayCount(videoCacheBean.getPlayCount()+1);videoCacheBean.setPlayTime(System.currentTimeMillis());VideoCacheDBUtil.save(videoCacheBean);}

⑤关于多个 Activity 同步播放状态, 无缝切换

1.首先在跳转时, 通知被覆盖的 activity 不关闭播放器

//首先跳转时通知一下 activitymainActivity.jumpNotCloseMediaPlay(position);//然后在 onPause 里
protected void onPause() {super.onPause();//如果要跳转播放, 那么不关闭播放器if (videoPositionList.size()>currentPlayIndex && jumpVideoPosition==videoPositionList.get(currentPlayIndex)) {...这里就不关闭播放器}else{//如果不要求跳转播放, 那么就重置播放器mMediaPlayerTool.reset();}
}

2.然后在新页面初始化播放器

private void playVideoByPosition(int position){......一切初始化代码照旧(注意不要重置播放器), 这里省略不提//把播放器当前绑定的 SurfaceTexture 取出起来, 设置给当前界面的 TextureViewvh.playTextureView.resetTextureView(mMediaPlayerTool.getAvailableSurfaceTexture());mMediaPlayerTool.setPlayTextureView(vh.playTextureView);//最后刷新一下 viewvh.playTextureView.postInvalidate();
}

至此代码讲解完毕, 亲测在 4g 网络下视频初始化速度毫秒级, 并且在低性能手机下, 页面来回切换无卡顿.

大家如果有不解, 可以查看源码了解更多, 有 bug 或优化思路也可以提issues