Question

我正在尝试在Android中传输视频。对于一个uri，它可以正常工作，如果我去另一个它抛出非法状态异常。其实我的代码是

public class VideoSample extends Activity implements OnSeekBarChangeListener, Callback,         OnPreparedListener, OnCompletionListener, OnBufferingUpdateListener,
    OnClickListener, OnSeekCompleteListener, AnimationListener {
private TextView textViewPlayed;
private TextView textViewLength;
private SeekBar seekBarProgress;
private SurfaceView surfaceViewFrame;
private ImageView imageViewPauseIndicator;
private MediaPlayer player;
private SurfaceHolder holder;
private ProgressBar progressBarWait;
private Timer updateTimer;
private Bundle extras;
private Animation hideMediaController;
private LinearLayout linearLayoutMediaController;
private static final String TAG = "androidEx2 = VideoSample";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.videosample);
    extras = getIntent().getExtras();

    linearLayoutMediaController = (LinearLayout) findViewById(R.id.linearLayoutMediaController);
    linearLayoutMediaController.setVisibility(View.GONE);

    hideMediaController = AnimationUtils.loadAnimation(this, R.anim.disapearing);
    hideMediaController.setAnimationListener(this);

    imageViewPauseIndicator = (ImageView) findViewById(R.id.imageViewPauseIndicator);
    imageViewPauseIndicator.setVisibility(View.GONE);
    if (player != null) {
        if (!player.isPlaying()) {
            imageViewPauseIndicator.setVisibility(View.VISIBLE);
        }
    }

    textViewPlayed = (TextView) findViewById(R.id.textViewPlayed);
    textViewLength = (TextView) findViewById(R.id.textViewLength);

    surfaceViewFrame = (SurfaceView) findViewById(R.id.surfaceViewFrame);
    surfaceViewFrame.setOnClickListener(this);
    surfaceViewFrame.setClickable(false);

    seekBarProgress = (SeekBar) findViewById(R.id.seekBarProgress);
    seekBarProgress.setOnSeekBarChangeListener(this);
    seekBarProgress.setProgress(0);

    progressBarWait = (ProgressBar) findViewById(R.id.progressBarWait);

    holder = surfaceViewFrame.getHolder();
    holder.addCallback(this);

    player = new MediaPlayer();
    player.setOnPreparedListener(this);
    player.setOnCompletionListener(this);
    player.setOnBufferingUpdateListener(this);
    player.setOnSeekCompleteListener(this);
    player.setScreenOnWhilePlaying(true);

}

private void playVideo() {
    if (extras.getString("video_path").equals("VIDEO_URI")) {
        showToast("Please, set the video URI in HelloAndroidActivity.java in onClick(View v) method");
    } else {
        new Thread(new Runnable() {
            public void run() {
                try {
                    player.setDataSource(extras.getString("video_path"));
                    Log.i(TAG, extras.getString("video_path"));
                    player.prepare();
                } catch (IllegalArgumentException e) {
                    showToast("Error while playing video Argument");
                    Log.i(TAG, "========== IllegalArgumentException ===========");
                    e.printStackTrace();
                } catch (IllegalStateException e) {
                    showToast("Error while playing video State");
                    Log.i(TAG, "========== IllegalStateException ===========");
                    e.printStackTrace();
                } catch (IOException e) {
                    showToast("Error while playing video. Please, check your network connection.");
                    Log.i(TAG, "========== IOException ===========");
                    e.printStackTrace();
                }
            }
        }).start();
    }
}

private void showToast(final String string) {
    runOnUiThread(new Runnable() {
        public void run() {
            Toast.makeText(VideoSample.this, string, Toast.LENGTH_LONG).show();
            finish();
        }
    });
}

private void hideMediaController() {
    new Thread(new Runnable() {
        public void run() {
            try {
                Thread.sleep(5000);
                runOnUiThread(new Runnable() {
                    public void run() {
                        linearLayoutMediaController.startAnimation(hideMediaController);
                    }
                });
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }).start();
}

public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
    Log.i(TAG, "========== onProgressChanged : " + progress + " from user: " + fromUser);
    if (!fromUser) {
        textViewPlayed.setText(Utils.durationInSecondsToString(progress));
    }
}

public void onStartTrackingTouch(SeekBar seekBar) {
    // TODO Auto-generated method stub
}

public void onStopTrackingTouch(SeekBar seekBar) {
    if (player.isPlaying()) {
        progressBarWait.setVisibility(View.VISIBLE);
        player.seekTo(seekBar.getProgress() * 1000);
        Log.i(TAG, "========== SeekTo : " + seekBar.getProgress());
    }
}

public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    // TODO Auto-generated method stub

}

public void surfaceCreated(SurfaceHolder holder) {
    player.setDisplay(holder);
    playVideo();
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // TODO Auto-generated method stub

}

public void onPrepared(MediaPlayer mp) {
    Log.i(TAG, "========== onPrepared ===========");
    int duration = mp.getDuration() / 1000; // duration in seconds
    seekBarProgress.setMax(duration);
    textViewLength.setText(Utils.durationInSecondsToString(duration));
    progressBarWait.setVisibility(View.GONE);

    // Get the dimensions of the video
    int videoWidth = player.getVideoWidth();
    int videoHeight = player.getVideoHeight();
    float videoProportion = (float) videoWidth / (float) videoHeight;
    Log.i(TAG, "VIDEO SIZES: W: " + videoWidth + " H: " + videoHeight + " PROP: " + videoProportion);

    // Get the width of the screen
    int screenWidth = getWindowManager().getDefaultDisplay().getWidth();
    int screenHeight = getWindowManager().getDefaultDisplay().getHeight();
    float screenProportion = (float) screenWidth / (float) screenHeight;
    Log.i(TAG, "VIDEO SIZES: W: " + screenWidth + " H: " + screenHeight + " PROP: " + screenProportion);

    // Get the SurfaceView layout parameters
    android.view.ViewGroup.LayoutParams lp = surfaceViewFrame.getLayoutParams();

    if (videoProportion > screenProportion) {
        lp.width = screenWidth;
        lp.height = (int) ((float) screenWidth / videoProportion);
    } else {
        lp.width = (int) (videoProportion * (float) screenHeight);
        lp.height = screenHeight;
    }

    // Commit the layout parameters
    surfaceViewFrame.setLayoutParams(lp);

    // Start video
    if (!player.isPlaying()) {
        player.start();
        updateMediaProgress();
        linearLayoutMediaController.setVisibility(View.VISIBLE);
        hideMediaController();
    }
    surfaceViewFrame.setClickable(true);
}

public void onCompletion(MediaPlayer mp) {
    mp.stop();
    if (updateTimer != null) {
        updateTimer.cancel();
    }
    finish();
}

@Override
protected void onStop() {
    // TODO Auto-generated method stub
    super.onStop();
    player.release();
}

/**
 * Change progress of mediaController
 * */
private void updateMediaProgress() {
    updateTimer = new Timer("progress Updater");
    updateTimer.scheduleAtFixedRate(new TimerTask() {
        @Override
        public void run() {
            runOnUiThread(new Runnable() {
                public void run() {
                    seekBarProgress.setProgress(player.getCurrentPosition() / 1000);
                }
            });
        }
    }, 0, 1000);
}

public void onBufferingUpdate(MediaPlayer mp, int percent) {
    int progress = (int) ((float) mp.getDuration() * ((float) percent / (float) 100));
    seekBarProgress.setSecondaryProgress(progress / 1000);
}

public void onClick(View v) {
    if (v.getId() == R.id.surfaceViewFrame) {
        if (linearLayoutMediaController.getVisibility() == View.GONE) {
            linearLayoutMediaController.setVisibility(View.VISIBLE);
            hideMediaController();
        } else if (player != null) {
            if (player.isPlaying()) {
                player.pause();
                imageViewPauseIndicator.setVisibility(View.VISIBLE);
            } else {
                player.start();
                imageViewPauseIndicator.setVisibility(View.GONE);
            }
        }
    }
}

public void onSeekComplete(MediaPlayer mp) {
    progressBarWait.setVisibility(View.GONE);
}

public void onAnimationEnd(Animation animation) {
    // TODO Auto-generated method stub

}

public void onAnimationRepeat(Animation animation) {
    // TODO Auto-generated method stub

}

public void onAnimationStart(Animation animation) {
    linearLayoutMediaController.setVisibility(View.GONE);
}
}

这是工作的uri http://www.pocketjourney.com/downloads/pj/video/famous.3gp

这个会在mp.prepare（）http://www.fieldandrurallife.tv/videos/Benltey%20Mulsanne.mp4

中抛出illegalstateexception

Answer 1

为了在Android设备上流式传输视频，您可以使用VideoView类。 VideoView类可以从各种来源加载图像，负责从视频计算其测量值，以便可以在任何布局管理器中使用，并提供各种显示选项，如缩放和着色。

我已经尝试了一个错误的视频，效果很好。您将在下面找到我用于测试您的视频流媒体链接的代码：

VideoView videoview;
videoview = (VideoView) findViewById(R.id.VideoView);
try {
    MediaController mediacontroller = new MediaController(VideoViewerActivity.this);
    mediacontroller.setAnchorView(videoview);
    Uri video = Uri.parse("http://www.fieldandrurallife.tv/videos/Benltey%20Mulsanne.mp4");
    videoview.setMediaController(mediacontroller);
    videoview.setVideoURI(video);
    } catch (Exception e) {
        e.printStackTrace();
    }
videoview.requestFocus();
videoview.setOnPreparedListener(new OnPreparedListener() {
        public void onPrepared(MediaPlayer mp) {
            videoview.setZOrderOnTop(true);
            videoview.start();
        }
    });

不要忘记将videoView放在.xml文件中：

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >
    <VideoView
        android:id="@+id/VideoView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
         />    
</RelativeLayout>

如果您对我的回答有任何疑问，请随时与我联系。祝你好运

Answer 2

当您获得player.prepare（）的非法状态异常时，您可以尝试在相应的catch块中重新启动MediaPlayer对象，如下面的代码片段所示。（最好在准备好mediaPlayer之后调用start（））：

try{
    player.prepare();
}catch (IllegalStateException e) {
    player = new MediaPlayer();
    player.setDataSource(extras.getString("video_path"));
    Log.i(TAG, extras.getString("video_path"));
    player.prepare();
    player.setOnPreparedListener(new OnPreparedListener(){
       @Override
       public void onPrepared(MediaPlayer mp){
       mp.start();
       }
    });
}

MediaPlayer.prepare（）THROWS非法状态异常

2 个答案: