android Multimedia实战（一）详解SurfaceView，TextureView之播放视频的四种方式

android Multimedia实战系列将聚焦于Android Multimedia模块，结合Android5.X到Android7.X或者到后来8.x 9.x最新Multimedia相关的API等，实现录制音视频，播放音视频，截图，录屏，编解码等实用功能！

下面不废话直接入正文：
github完整demo，欢迎star:https://github.com/WangShuo1143368701/VideoView
在Android中，我们有四种方式来实现视频的播放：
1、使用其自带的播放器。指定Action为ACTION_VIEW,Data为Uri，Type为其MIME类型。

2、使用VideoView来播放。在布局文件中使用VideoView结合MediaController来实现对其控制。

3、使用MediaPlayer类和SurfaceView来实现，这种方式很灵活。

4、使用MediaPlayer类和TextureView来实现，这种方式更灵活。

下面看代码示例：
1、调用其自带的播放器：

Uri uri = Uri.parse(Environment.getExternalStorageDirectory().getPath()+"/Test_Movie.m4v");     
//调用系统自带的播放器    
    Intent intent = new Intent(Intent.ACTION_VIEW);    
    Log.v("URI:::::::::", uri.toString());    
    intent.setDataAndType(uri, "video/mp4");    
    startActivity(intent); 

2、使用VideoView来实现：

Uri uri = Uri.parse(Environment.getExternalStorageDirectory().getPath()+"/Test_Movie.m4v");    
VideoView videoView = (VideoView)this.findViewById(R.id.video_view);    
videoView.setMediaController(new MediaController(this));    
videoView.setVideoURI(uri);    
videoView.start();    
videoView.requestFocus();

在介绍三四中方式之前我们先比较一下SurfaceView及TextureView

SurfaceView优点及缺点：
优点：可以在一个独立的线程中进行绘制，不会影响主线程
使用双缓冲机制，播放视频时画面更流畅

缺点：Surface不在View hierachy中，它的显示也不受View的属性控制，所以不能进行平移，缩放等变换，也不能放在其它ViewGroup中。SurfaceView 不能嵌套使用

TextureView优点及缺点：
优点：支持移动、旋转、缩放等动画，支持截图

缺点：必须在硬件加速的窗口中使用，占用内存比SurfaceView高，在5.0以前在主线程渲染，5.0以后有单独的渲染线程。

小结：
从性能和安全性角度出发，使用播放器优先选SurfaceView。

1、在android 7.0上系统surfaceview的性能比TextureView更有优势，支持对象的内容位置和包含的应用内容同步更新，平移、缩放不会产生黑边。 在7.0以下系统如果使用场景有动画效果，可以选择性使用TextureView

2、由于失效(invalidation)和缓冲的特性，TextureView增加了额外1~3帧的延迟显示画面更新

3、TextureView总是使用GL合成，而SurfaceView可以使用硬件overlay后端，可以占用更少的内存带宽，消耗更少的能量

4、TextureView的内部缓冲队列导致比SurfaceView使用更多的内存

5、SurfaceView： 内部自己持有surface，surface 创建、销毁、大小改变时系统来处理的，通过surfaceHolder 的callback回调通知。当画布创建好时，可以将surface绑定到MediaPlayer中。SurfaceView如果为用户可见的时候，创建SurfaceView的SurfaceHolder用于显示视频流解析的帧图片，如果发现SurfaceView变为用户不可见的时候，则立即销毁SurfaceView的SurfaceHolder，以达到节约系统资源的目的

3、使用MediaPlayer类和SurfaceView来实现

package com.ws.videoview.videoview.view;


import android.content.Context;
import android.graphics.PixelFormat;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnInfoListener;
import android.media.MediaPlayer.OnVideoSizeChangedListener;
import android.net.Uri;
import android.os.Build;
import android.os.Handler;
import android.os.Message;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.util.Log;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;

import java.io.IOException;



/**
 * Created by Shuo.Wang on 2017/4/25.
 */

public class SurfaceVideoView extends SurfaceView implements Callback {

    /** 定时暂停 */
    private static final int HANDLER_MESSAGE_PARSE = 0;
    /** 定时循环 */
    private static final int HANDLER_MESSAGE_LOOP = 1;

    private MediaPlayer.OnCompletionListener mOnCompletionListener;
    private MediaPlayer.OnPreparedListener mOnPreparedListener;
    private MediaPlayer.OnErrorListener mOnErrorListener;
    private MediaPlayer.OnSeekCompleteListener mOnSeekCompleteListener;
    private OnInfoListener mOnInfoListener;
    private OnVideoSizeChangedListener mOnVideoSizeChangedListener;
    private OnPlayStateListener mOnPlayStateListener;
    private MediaPlayer mMediaPlayer = null;
    private SurfaceHolder mSurfaceHolder = null;

    private static final int STATE_ERROR = -1;
    private static final int STATE_IDLE = 0;
    private static final int STATE_PREPARING = 1;
    private static final int STATE_PREPARED = 2;
    private static final int STATE_PLAYING = 3;
    private static final int STATE_PAUSED = 4;
    /**
     * PlaybackCompleted状态：文件正常播放完毕，而又没有设置循环播放的话就进入该状态，
     * 并会触发OnCompletionListener的onCompletion
     * ()方法。此时可以调用start()方法重新从头播放文件，也可以stop()停止MediaPlayer，或者也可以seekTo()来重新定位播放位置。
     */
    private static final int STATE_PLAYBACK_COMPLETED = 5;
    /** Released/End状态：通过release()方法可以进入End状态 */
    private static final int STATE_RELEASED = 5;

    private int mCurrentState = STATE_IDLE;
    private int mTargetState = STATE_IDLE;

    private int mVideoWidth;
    private int mVideoHeight;
    //  private int mSurfaceWidth;
    //  private int mSurfaceHeight;

    //  private float mSystemVolumn = -1;
    private int mDuration;
    private Uri mUri;

    //  SurfaceTextureAvailable

    public SurfaceVideoView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initVideoView();
    }

    public SurfaceVideoView(Context context) {
        super(context);
        initVideoView();
    }

    public SurfaceVideoView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initVideoView();
    }

    @SuppressWarnings("deprecation")
    protected void initVideoView() {
        //      mTryCount = 0;
        mVideoWidth = 0;
        mVideoHeight = 0;

        getHolder().setFormat(PixelFormat.RGBA_8888); // PixelFormat.RGB_565
        getHolder().addCallback(this);
        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB) {
            getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }

        setFocusable(true);
        setFocusableInTouchMode(true);
        requestFocus();

        mCurrentState = STATE_IDLE;
        mTargetState = STATE_IDLE;
    }

    /** 更新音量 */
    public static float getSystemVolumn(Context context) {
        if (context != null) {
            try {
                AudioManager mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
                int maxVolumn = mAudioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
                return mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC) * 1.0F / maxVolumn;
            } catch (UnsupportedOperationException e) {

            }
        }
        return 0.5F;
    }

    public void setOnInfoListener(OnInfoListener l) {
        mOnInfoListener = l;
    }

    public void setOnVideoSizeChangedListener(OnVideoSizeChangedListener l) {
        mOnVideoSizeChangedListener = l;
    }

    public void setOnPreparedListener(MediaPlayer.OnPreparedListener l) {
        mOnPreparedListener = l;
    }

    public void setOnErrorListener(MediaPlayer.OnErrorListener l) {
        mOnErrorListener = l;
    }

    public void setOnPlayStateListener(OnPlayStateListener l) {
        mOnPlayStateListener = l;
    }

    public void setOnSeekCompleteListener(MediaPlayer.OnSeekCompleteListener l) {
        mOnSeekCompleteListener = l;
    }

    public static interface OnPlayStateListener {
        public void onStateChanged(boolean isPlaying);
    }

    public void setOnCompletionListener(MediaPlayer.OnCompletionListener l) {
        mOnCompletionListener = l;
    }

    public void setVideoPath(String path) {
        // && MediaUtils.isNative(path)
        if (!TextUtils.isEmpty(path)) {
            mTargetState = STATE_PREPARED;
            openVideo(Uri.parse(path));
        }
    }

    public int getVideoWidth() {
        return mVideoWidth;
    }

    public int getVideoHeight() {
        return mVideoHeight;
    }

    public void reOpen() {
        mTargetState = STATE_PREPARED;
        openVideo(mUri);
    }

    public int getDuration() {
        return mDuration;
    }

    /** 重试 */
    private void tryAgain(Exception e) {
        mCurrentState = STATE_ERROR;
        openVideo(mUri);
    }

    public void start() {
        mTargetState = STATE_PLAYING;
        //可用状态{Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                if (!isPlaying())
                    mMediaPlayer.start();
                mCurrentState = STATE_PLAYING;
                if (mOnPlayStateListener != null)
                    mOnPlayStateListener.onStateChanged(true);
            } catch (IllegalStateException e) {
                tryAgain(e);
            } catch (Exception e) {
                tryAgain(e);
            }
        }
    }

    public void pause() {
        mTargetState = STATE_PAUSED;
        //可用状态{Started, Paused}
        if (mMediaPlayer != null && (mCurrentState == STATE_PLAYING)) {
            try {
                mMediaPlayer.pause();
                mCurrentState = STATE_PAUSED;
                if (mOnPlayStateListener != null)
                    mOnPlayStateListener.onStateChanged(false);
            } catch (IllegalStateException e) {
                tryAgain(e);
            } catch (Exception e) {
                tryAgain(e);
            }
        }
    }

    /** 处理音量键 */
    public void dispatchKeyEvent(Context context, KeyEvent event) {
        switch (event.getKeyCode()) {
            case KeyEvent.KEYCODE_VOLUME_DOWN:
            case KeyEvent.KEYCODE_VOLUME_UP:
                setVolume(getSystemVolumn(context));
                break;
        }
    }

    public void setVolume(float volume) {
        //可用状态{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                mMediaPlayer.setVolume(volume, volume);
            } catch (Exception e) {

            }
        }
    }

    //  public float getSystemVolume() {
    //      return mSystemVolumn;
    //  }

    public void setLooping(boolean looping) {
        //可用状态{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                mMediaPlayer.setLooping(looping);
            } catch (Exception e) {
            }
        }
    }

    public void seekTo(int msec) {
        //可用状态{Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                if (msec < 0)
                    msec = 0;
                mMediaPlayer.seekTo(msec);
            } catch (IllegalStateException e) {
            } catch (Exception e) {
            }
        }
    }

    /** 获取当前播放位置 */
    public int getCurrentPosition() {
        int position = 0;
        //可用状态{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}
        if (mMediaPlayer != null) {
            switch (mCurrentState) {
                case STATE_PLAYBACK_COMPLETED:
                    position = getDuration();
                    break;
                case STATE_PLAYING:
                case STATE_PAUSED:
                    try {
                        position = mMediaPlayer.getCurrentPosition();
                    } catch (IllegalStateException e) {
                    } catch (Exception e) {
                    }
                    break;
            }
        }
        return position;
    }

    public boolean isPlaying() {
        //可用状态{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}
        if (mMediaPlayer != null && mCurrentState == STATE_PLAYING) {
            try {
                return mMediaPlayer.isPlaying();
            } catch (IllegalStateException e) {
            } catch (Exception e) {
            }
        }
        return false;
    }

    /** 调用release方法以后MediaPlayer无法再恢复使用 */
    public void release() {
        mTargetState = STATE_RELEASED;
        mCurrentState = STATE_RELEASED;
        if (mMediaPlayer != null) {
            try {
                mMediaPlayer.release();
            } catch (IllegalStateException e) {
            } catch (Exception e) {
            }
            mMediaPlayer = null;
        }
    }

    public SurfaceHolder getSurfaceHolder() {
        return mSurfaceHolder;
    }

    public void openVideo(Uri uri) {
        if (uri == null || mSurfaceHolder == null || getContext() == null) {
            // not ready for playback just yet, will try again later
            if (mSurfaceHolder == null && uri != null) {
                mUri = uri;
            }
            Log.e("openVideo ws--->","openVideo return");
            return;
        }

        mUri = uri;
        mDuration = 0;

        //Idle 状态：当使用new()方法创建一个MediaPlayer对象或者调用了其reset()方法时，该MediaPlayer对象处于idle状态。
        //End 状态：通过release()方法可以进入End状态，只要MediaPlayer对象不再被使用，就应当尽快将其通过release()方法释放掉
        //Initialized 状态：这个状态比较简单，MediaPlayer调用setDataSource()方法就进入Initialized状态，表示此时要播放的文件已经设置好了。
        //Prepared 状态：初始化完成之后还需要通过调用prepare()或prepareAsync()方法，这两个方法一个是同步的一个是异步的，只有进入Prepared状态，才表明MediaPlayer到目前为止都没有错误，可以进行文件播放。

        Exception exception = null;
        try {
            if (mMediaPlayer == null) {
                mMediaPlayer = new MediaPlayer();
                mMediaPlayer.setOnPreparedListener(mPreparedListener);
                mMediaPlayer.setOnCompletionListener(mCompletionListener);
                mMediaPlayer.setOnErrorListener(mErrorListener);
                mMediaPlayer.setOnVideoSizeChangedListener(mVideoSizeChangedListener);
                mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                mMediaPlayer.setOnSeekCompleteListener(mSeekCompleteListener);
                mMediaPlayer.setOnInfoListener(mInfoListener);
                //          mMediaPlayer.setScreenOnWhilePlaying(true);
                //              mMediaPlayer.setVolume(mSystemVolumn, mSystemVolumn);
                mMediaPlayer.setDisplay(mSurfaceHolder);
            } else {
                mMediaPlayer.reset();
            }
            mMediaPlayer.setDataSource(getContext(), uri);

            //          if (mLooping)
            //              mMediaPlayer.setLooping(true);//循环播放
            mMediaPlayer.prepareAsync();
            // we don't set the target state here either, but preserve the
            // target state that was there before.
            mCurrentState = STATE_PREPARING;
        } catch (IOException ex) {
            exception = ex;
        } catch (IllegalArgumentException ex) {
            exception = ex;
        } catch (Exception ex) {
            exception = ex;
        }
        if (exception != null) {
            mCurrentState = STATE_ERROR;
            if (mErrorListener != null)
                mErrorListener.onError(mMediaPlayer, MediaPlayer.MEDIA_ERROR_UNKNOWN, 0);
        }
    }

    private MediaPlayer.OnCompletionListener mCompletionListener = new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mp) {
            mCurrentState = STATE_PLAYBACK_COMPLETED;
            //          mTargetState = STATE_PLAYBACK_COMPLETED;
            if (mOnCompletionListener != null)
                mOnCompletionListener.onCompletion(mp);
        }
    };

    MediaPlayer.OnPreparedListener mPreparedListener = new MediaPlayer.OnPreparedListener() {
        @Override
        public void onPrepared(MediaPlayer mp) {
            //必须是正常状态
            if (mCurrentState == STATE_PREPARING) {
                mCurrentState = STATE_PREPARED;
                try {
                    mDuration = mp.getDuration();
                } catch (IllegalStateException e) {
                }

                try {
                    mVideoWidth = mp.getVideoWidth();
                    mVideoHeight = mp.getVideoHeight();
                } catch (IllegalStateException e) {
                }

                switch (mTargetState) {
                    case STATE_PREPARED:
                        if (mOnPreparedListener != null)
                            mOnPreparedListener.onPrepared(mMediaPlayer);
                        break;
                    case STATE_PLAYING:
                        start();
                        break;
                }
            }
        }
    };

    OnVideoSizeChangedListener mVideoSizeChangedListener = new OnVideoSizeChangedListener() {

        @Override
        public void onVideoSizeChanged(MediaPlayer mp, int width, int height) {
            mVideoWidth = width;
            mVideoHeight = height;
            if (mOnVideoSizeChangedListener != null)
                mOnVideoSizeChangedListener.onVideoSizeChanged(mp, width, height);
        }

    };

    OnInfoListener mInfoListener = new OnInfoListener() {

        @Override
        public boolean onInfo(MediaPlayer mp, int what, int extra) {
            if (mOnInfoListener != null)
                mOnInfoListener.onInfo(mp, what, extra);
            return false;
        }
    };

    private MediaPlayer.OnSeekCompleteListener mSeekCompleteListener = new MediaPlayer.OnSeekCompleteListener() {

        @Override
        public void onSeekComplete(MediaPlayer mp) {
            if (mOnSeekCompleteListener != null)
                mOnSeekCompleteListener.onSeekComplete(mp);
        }
    };

    private MediaPlayer.OnErrorListener mErrorListener = new MediaPlayer.OnErrorListener() {
        @Override
        public boolean onError(MediaPlayer mp, int framework_err, int impl_err) {
            mCurrentState = STATE_ERROR;
            //          mTargetState = STATE_ERROR;
            //FIX，可以考虑出错以后重新开始
            if (mOnErrorListener != null)
                mOnErrorListener.onError(mp, framework_err, impl_err);

            return true;
        }
    };

    /** 是否可用 */
    public boolean isPrepared() {
        return mMediaPlayer != null && (mCurrentState == STATE_PREPARED);
    }

    public boolean isComplate(){
        return mMediaPlayer != null && (mCurrentState == STATE_PLAYBACK_COMPLETED);
    }

    /** 是否已经释放 */
    public boolean isRelease() {
        return mMediaPlayer == null || mCurrentState == STATE_IDLE || mCurrentState == STATE_ERROR || mCurrentState == STATE_RELEASED;
    }

    private Handler mVideoHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case HANDLER_MESSAGE_PARSE:
                    pause();
                    break;
                case HANDLER_MESSAGE_LOOP:
                    if (isPlaying()) {
                        seekTo(msg.arg1);
                        sendMessageDelayed(mVideoHandler.obtainMessage(HANDLER_MESSAGE_LOOP, msg.arg1, msg.arg2), msg.arg2);
                    }
                    break;
                default:
                    break;
            }
            super.handleMessage(msg);
        }
    };

    /** 定时暂停 */
    public void pauseDelayed(int delayMillis) {
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_PARSE))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_PARSE);
        mVideoHandler.sendEmptyMessageDelayed(HANDLER_MESSAGE_PARSE, delayMillis);
    }

    /** 暂停并且清除定时任务 */
    public void pauseClearDelayed() {
        pause();
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_PARSE))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_PARSE);
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_LOOP))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_LOOP);
    }

    /** 区域内循环播放 */
    public void loopDelayed(int startTime, int endTime) {
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_PARSE))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_PARSE);
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_LOOP))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_LOOP);
        int delayMillis = endTime - startTime;
        seekTo(startTime);
        if (!isPlaying())
            start();
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_LOOP))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_LOOP);
        mVideoHandler.sendMessageDelayed(mVideoHandler.obtainMessage(HANDLER_MESSAGE_LOOP, getCurrentPosition(), delayMillis), delayMillis);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        boolean needReOpen = (mSurfaceHolder == null);
        mSurfaceHolder = holder;
        if (needReOpen) {
            reOpen();
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        mSurfaceHolder = holder;
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        mSurfaceHolder = null;
        release();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

4、使用MediaPlayer类和TextureView来实现，这种方式更灵活。

TextureView特有API
1 getSurfaceTexture()
This method returns the SurfaceTexture used by this view.

2 getBitmap(int width, int height)
This method returns Returns a Bitmap representation of the content of the associated surface texture.

3 getTransform(Matrix transform)
This method returns the transform associated with this texture view.

4 isOpaque()
This method indicates whether this View is opaque.

5 lockCanvas()
This method start editing the pixels in the surface

6 setOpaque(boolean opaque)
This method indicates whether the content of this TextureView is opaque.

7 setTransform(Matrix transform)
This method sets the transform to associate with this texture view.

8 unlockCanvasAndPost(Canvas canvas)
This method finish editing pixels in the surface.

9 setAlpha和setRotation

package com.ws.videoview.videoview.view;

/**
 * Created by Shuo.Wang on 2017/4/25.
 */

import android.content.Context;
import android.graphics.SurfaceTexture;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.view.Surface;
import android.view.TextureView;

import java.io.IOException;

public class TextureVideoView extends TextureView implements TextureView.SurfaceTextureListener {

    private MediaPlayer.OnCompletionListener mOnCompletionListener;
    private MediaPlayer.OnPreparedListener mOnPreparedListener;
    private MediaPlayer.OnErrorListener mOnErrorListener;
    private MediaPlayer.OnSeekCompleteListener mOnSeekCompleteListener;
    private OnPlayStateListener mOnPlayStateListener;
    private MediaPlayer mMediaPlayer = null;
    private SurfaceTexture mSurfaceHolder = null;

    private static final int STATE_ERROR = -1;
    private static final int STATE_IDLE = 0;
    private static final int STATE_PREPARING = 1;
    private static final int STATE_PREPARED = 2;
    private static final int STATE_PLAYING = 3;
    private static final int STATE_PAUSED = 4;
    private static final int STATE_STOP = 5;
    /**
     * PlaybackCompleted状态：文件正常播放完毕，而又没有设置循环播放的话就进入该状态，
     * 并会触发OnCompletionListener的onCompletion
     * ()方法。此时可以调用start()方法重新从头播放文件，也可以stop()停止MediaPlayer，或者也可以seekTo()来重新定位播放位置。
     */
    private static final int STATE_PLAYBACK_COMPLETED = 5;
    /** Released/End状态：通过release()方法可以进入End状态 */
    private static final int STATE_RELEASED = 5;

    private int mCurrentState = STATE_IDLE;
    private int mTargetState = STATE_IDLE;

    private int mVideoWidth;
    private int mVideoHeight;
    //  private int mSurfaceWidth;
    //  private int mSurfaceHeight;

    private float mVolumn = -1;
    private int mDuration;
    private Uri mUri;

    //  SurfaceTextureAvailable

    public TextureVideoView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initVideoView();
    }

    public TextureVideoView(Context context) {
        super(context);
        initVideoView();
    }

    public TextureVideoView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initVideoView();
    }

    public MediaPlayer getMediaPlayer(){
        return mMediaPlayer;
    }

    protected void initVideoView() {
        try {
            AudioManager mAudioManager = (AudioManager) getContext().getSystemService(Context.AUDIO_SERVICE);
            mVolumn = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
        } catch (UnsupportedOperationException e) {

        }
        //      mTryCount = 0;
        mVideoWidth = 0;
        mVideoHeight = 0;
        setSurfaceTextureListener(this);
        //      setFocusable(true);
        //      setFocusableInTouchMode(true);
        //      requestFocus();
        mCurrentState = STATE_IDLE;
        mTargetState = STATE_IDLE;
    }

    public void setOnPreparedListener(MediaPlayer.OnPreparedListener l) {
        mOnPreparedListener = l;
    }

    public void setOnErrorListener(MediaPlayer.OnErrorListener l) {
        mOnErrorListener = l;
    }

    public void setOnPlayStateListener(OnPlayStateListener l) {
        mOnPlayStateListener = l;
    }

    public void setOnSeekCompleteListener(MediaPlayer.OnSeekCompleteListener l) {
        mOnSeekCompleteListener = l;
    }

    public static interface OnPlayStateListener {
        public void onStateChanged(boolean isPlaying);
    }

    public void setOnCompletionListener(MediaPlayer.OnCompletionListener l) {
        mOnCompletionListener = l;
    }

    public void setVideoPath(String path) {
//      if (StringUtils.isNotEmpty(path) && MediaUtils.isNative(path)) {
        mTargetState = STATE_PREPARED;
        openVideo(Uri.parse(path));
//      }
    }

    public int getVideoWidth() {
        return mVideoWidth;
    }

    public int getVideoHeight() {
        return mVideoHeight;
    }

    public void reOpen() {
        mTargetState = STATE_PREPARED;
        openVideo(mUri);
    }

    public int getDuration() {
        return mDuration;
    }

    /** 重试 */
    private void tryAgain(Exception e) {
        e.printStackTrace();
        mCurrentState = STATE_ERROR;
        openVideo(mUri);
    }

    public void start() {
        mTargetState = STATE_PLAYING;
        //可用状态{Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                if (!isPlaying())
                    mMediaPlayer.start();
                mCurrentState = STATE_PLAYING;
                if (mOnPlayStateListener != null)
                    mOnPlayStateListener.onStateChanged(true);
            } catch (IllegalStateException e) {
                tryAgain(e);
            } catch (Exception e) {
                tryAgain(e);
            }
        }
    }

    public void pause() {
        mTargetState = STATE_PAUSED;
        //可用状态{Started, Paused}
        if (mMediaPlayer != null && (mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED)) {
            try {
                mMediaPlayer.pause();
                mCurrentState = STATE_PAUSED;
                if (mOnPlayStateListener != null)
                    mOnPlayStateListener.onStateChanged(false);
            } catch (IllegalStateException e) {
                tryAgain(e);
            } catch (Exception e) {
                tryAgain(e);
            }
        }
    }

    public void stop(){
        mTargetState = STATE_STOP;
        if (mMediaPlayer != null && (mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED)) {
            try {
                mMediaPlayer.stop();
                mCurrentState = STATE_STOP;
                if (mOnPlayStateListener != null)
                    mOnPlayStateListener.onStateChanged(false);
            } catch (IllegalStateException e) {
                tryAgain(e);
            } catch (Exception e) {
                tryAgain(e);
            }
        }
    }

    public void setVolume(float volume) {
        //可用状态{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                mMediaPlayer.setVolume(volume, volume);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    public void setLooping(boolean looping) {
        //可用状态{Idle, Initialized, Stopped, Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                mMediaPlayer.setLooping(looping);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    public void seekTo(int msec) {
        //可用状态{Prepared, Started, Paused, PlaybackCompleted}
        if (mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PLAYING || mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYBACK_COMPLETED)) {
            try {
                if (msec < 0)
                    msec = 0;
                mMediaPlayer.seekTo(msec);
            } catch (IllegalStateException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    /** 获取当前播放位置 */
    public int getCurrentPosition() {
        int position = 0;
        //可用状态{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}
        if (mMediaPlayer != null) {
            switch (mCurrentState) {
                case STATE_PLAYBACK_COMPLETED:
                    position = getDuration();
                    break;
                case STATE_PLAYING:
                case STATE_PAUSED:
                    try {
                        position = mMediaPlayer.getCurrentPosition();
                    } catch (IllegalStateException e) {
                        e.printStackTrace();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                    break;
            }
        }
        return position;
    }

    public boolean isPlaying() {
        //可用状态{Idle, Initialized, Prepared, Started, Paused, Stopped, PlaybackCompleted}
        if (mMediaPlayer != null && mCurrentState == STATE_PLAYING) {
            try {
                return mMediaPlayer.isPlaying();
            } catch (IllegalStateException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return false;
    }

    /** 调用release方法以后MediaPlayer无法再恢复使用 */
    public void release() {
        mTargetState = STATE_RELEASED;
        mCurrentState = STATE_RELEASED;
        if (mMediaPlayer != null) {
            try {
                mMediaPlayer.release();
            } catch (IllegalStateException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }
            mMediaPlayer = null;
        }
    }

    public void openVideo(Uri uri) {
        if (uri == null || mSurfaceHolder == null || getContext() == null) {
            // not ready for playback just yet, will try again later
            if (mSurfaceHolder == null && uri != null) {
                mUri = uri;
            }
            return;
        }

        mUri = uri;
        mDuration = 0;

        //Idle 状态：当使用new()方法创建一个MediaPlayer对象或者调用了其reset()方法时，该MediaPlayer对象处于idle状态。
        //End 状态：通过release()方法可以进入End状态，只要MediaPlayer对象不再被使用，就应当尽快将其通过release()方法释放掉
        //Initialized 状态：这个状态比较简单，MediaPlayer调用setDataSource()方法就进入Initialized状态，表示此时要播放的文件已经设置好了。
        //Prepared 状态：初始化完成之后还需要通过调用prepare()或prepareAsync()方法，这两个方法一个是同步的一个是异步的，只有进入Prepared状态，才表明MediaPlayer到目前为止都没有错误，可以进行文件播放。

        Exception exception = null;
        try {
            if (mMediaPlayer == null) {
                mMediaPlayer = new MediaPlayer();
                mMediaPlayer.setOnPreparedListener(mPreparedListener);
                mMediaPlayer.setOnCompletionListener(mCompletionListener);
                mMediaPlayer.setOnErrorListener(mErrorListener);
                mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                mMediaPlayer.setOnSeekCompleteListener(mSeekCompleteListener);
                //          mMediaPlayer.setScreenOnWhilePlaying(true);
                mMediaPlayer.setVolume(mVolumn, mVolumn);
                mMediaPlayer.setSurface(new Surface(mSurfaceHolder));
            } else {
                mMediaPlayer.reset();
            }
            mMediaPlayer.setDataSource(getContext(), uri);

            //          if (mLooping)
            //              mMediaPlayer.setLooping(true);//循环播放
            mMediaPlayer.prepareAsync();
            // we don't set the target state here either, but preserve the
            // target state that was there before.
            mCurrentState = STATE_PREPARING;
        } catch (IOException ex) {
            exception = ex;
        } catch (IllegalArgumentException ex) {
            exception = ex;
        } catch (Exception ex) {
            exception = ex;
        }
        if (exception != null) {
            exception.printStackTrace();
            mCurrentState = STATE_ERROR;
            if (mErrorListener != null)
                mErrorListener.onError(mMediaPlayer, MediaPlayer.MEDIA_ERROR_UNKNOWN, 0);
        }
    }

    private MediaPlayer.OnCompletionListener mCompletionListener = new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mp) {
            mCurrentState = STATE_PLAYBACK_COMPLETED;
            //          mTargetState = STATE_PLAYBACK_COMPLETED;
            if (mOnCompletionListener != null)
                mOnCompletionListener.onCompletion(mp);
        }
    };

    MediaPlayer.OnPreparedListener mPreparedListener = new MediaPlayer.OnPreparedListener() {
        @Override
        public void onPrepared(MediaPlayer mp) {
            //必须是正常状态
            if (mCurrentState == STATE_PREPARING) {
                mCurrentState = STATE_PREPARED;
                try {
                    mDuration = mp.getDuration();
                } catch (IllegalStateException e) {
                    e.printStackTrace();
                }

                try {
                    mVideoWidth = mp.getVideoWidth();
                    mVideoHeight = mp.getVideoHeight();
                } catch (IllegalStateException e) {
                    e.printStackTrace();
                }

                switch (mTargetState) {
                    case STATE_PREPARED:
                        if (mOnPreparedListener != null)
                            mOnPreparedListener.onPrepared(mMediaPlayer);
                        break;
                    case STATE_PLAYING:
                        start();
                        break;
                }
            }
        }
    };

    private MediaPlayer.OnSeekCompleteListener mSeekCompleteListener = new MediaPlayer.OnSeekCompleteListener() {

        @Override
        public void onSeekComplete(MediaPlayer mp) {
            if (mOnSeekCompleteListener != null)
                mOnSeekCompleteListener.onSeekComplete(mp);
        }
    };

    private MediaPlayer.OnErrorListener mErrorListener = new MediaPlayer.OnErrorListener() {
        @Override
        public boolean onError(MediaPlayer mp, int framework_err, int impl_err) {
            mCurrentState = STATE_ERROR;
            //          mTargetState = STATE_ERROR;
            //FIX，可以考虑出错以后重新开始
            if (mOnErrorListener != null)
                mOnErrorListener.onError(mp, framework_err, impl_err);

            return true;
        }
    };

    @Override
    public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
        boolean needReOpen = (mSurfaceHolder == null);
        mSurfaceHolder = surface;
        if (needReOpen) {
            reOpen();
        }
    }

    @Override
    public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {

    }

    @Override
    public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
        //画布失效
        mSurfaceHolder = null;
        release();
        return true;
    }

    @Override
    public void onSurfaceTextureUpdated(SurfaceTexture surface) {

    }

    /** 是否可用 */
    public boolean isPrepared() {
        //|| mCurrentState == STATE_PAUSED || mCurrentState == STATE_PLAYING
        return mMediaPlayer != null && (mCurrentState == STATE_PREPARED);
    }

    //  /** 是否能即可播放 */
    //  public boolean canStart() {
    //      return mMediaPlayer != null && (mCurrentState == STATE_PREPARED || mCurrentState == STATE_PAUSED);
    //  }

    private static final int HANDLER_MESSAGE_PARSE = 0;
    private static final int HANDLER_MESSAGE_LOOP = 1;

    private Handler mVideoHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case HANDLER_MESSAGE_PARSE:
                    pause();
                    break;
                case HANDLER_MESSAGE_LOOP:
                    if (isPlaying()) {
                        seekTo(msg.arg1);
                        sendMessageDelayed(mVideoHandler.obtainMessage(HANDLER_MESSAGE_LOOP, msg.arg1, msg.arg2), msg.arg2);
                    }
                    break;
                default:
                    break;
            }
            super.handleMessage(msg);
        }
    };

    /** 定时暂停 */
    public void pauseDelayed(int delayMillis) {
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_PARSE))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_PARSE);
        mVideoHandler.sendEmptyMessageDelayed(HANDLER_MESSAGE_PARSE, delayMillis);
    }

    /** 暂停并且清除定时任务 */
    public void pauseClearDelayed() {
        pause();
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_PARSE))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_PARSE);
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_LOOP))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_LOOP);
    }

    /** 区域内循环播放 */
    public void loopDelayed(int startTime, int endTime) {
        int delayMillis = endTime - startTime;
        seekTo(startTime);
        if (!isPlaying())
            start();
        if (mVideoHandler.hasMessages(HANDLER_MESSAGE_LOOP))
            mVideoHandler.removeMessages(HANDLER_MESSAGE_LOOP);
        mVideoHandler.sendMessageDelayed(mVideoHandler.obtainMessage(HANDLER_MESSAGE_LOOP, getCurrentPosition(), delayMillis), delayMillis);
    }
}