表面已经释放androidException

Question

我创建了媒体播放器运行时我有更改网址但是表面视图是黑色的，预期网址没有播放我在我的logcat中发现了一些错误我发布了我的错误和媒体播放器代码。为什么会这样？

代码：

public class MediaPlayerActivity extends Activity implements
        SurfaceHolder.Callback, OnCompletionListener, OnClickListener {

    /**
     * MediaPlayer Field
     */
    private MediaPlayer mediaPlayer;
    /**
     * surfaceHolder Field
     */
    private SurfaceHolder surfaceHolder;
    /**
     * playerSurfaceView Field
     */
    private SurfaceView playerSurfaceView;
    /**
     * wifiUSerName Field
     */
    private static String wifiUSerName = "RMS";
    /**
     * List of Url Field
     */
    private static List<Playfile> urls;
    /**
     * Button previous
     */
    private Button prevButton;
    /**
     * Button play And Pause
     */
    private Button playAndPauseButton;
    /**
     * Button Next
     */
    private Button nextButton;
    /**
     * seekbar Field
     */
    private SeekBar seekbar;
    /**
     * currentIndex Field
     */
    private int currentIndex = 0;
    /**
     * PlayMode boolean
     */
    private boolean isPlayMode = false;
    /**
     * FooterLayoutShow boolean
     */
    private boolean isFooterLayoutShow = false;
    /**
     * progressDialog Field
     */
    private ProgressDialog progressDialog;
    /**
     * Runnable Field to run on Every Second
     */
    private Runnable onEverySecond = null;
    /**
     * FrameLayout Field
     */
    private FrameLayout rootFrameLayout;
    /**
     * RelativeLayout footerButton
     */
    private RelativeLayout footerButtonLayout;

    // private ProgressBar progBar;

    /**
     * Method is called at very first time. set ui.
     */
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_media_player);

        initViewControls();
        getDataFromBundle();
        /*
         * if (MainActivity.progress.isShowing()) {
         * MainActivity.progress.dismiss(); }
         */
        mediaPlayer = new MediaPlayer();

    }

    /**
     * Method is used to initialize media player object and flag, set default
     * text on button.
     */
    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        mediaPlayer = new MediaPlayer();
        isPlayMode = true;
        playAndPauseButton.setBackgroundResource(R.drawable.pause);
        // Reset Urls
        urls = MasterData.getValueBasedOnKey(wifiUSerName);
    }

    /**
     * Method is used to get data from bundle.
     */
    private void getDataFromBundle() {
        if (getIntent().getExtras() != null) {
            Bundle bundle = getIntent().getExtras();

            wifiUSerName = bundle.getString("wifiusername");
            urls = MasterData.getValueBasedOnKey(wifiUSerName);
        } else {
            showToast("No data available");
            // Take the user to home
            Intent homeIntent = new Intent(Intent.ACTION_MAIN);
            homeIntent.addCategory(Intent.CATEGORY_HOME);
            homeIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            startActivity(homeIntent);
        }

    }

    /**
     * Method is used to initialise view controls.
     */
    private void initViewControls() {
        playerSurfaceView = (SurfaceView) findViewById(R.id.playersurface);
        prevButton = (Button) findViewById(R.id.activity_mediaplayer_prev_btn);
        playAndPauseButton = (Button) findViewById(R.id.activity_mediaplayer_play_and_pause_btn);
        nextButton = (Button) findViewById(R.id.activity_mediaplayer_next_btn);
        seekbar = (SeekBar) findViewById(R.id.activity_mediaplayer_seekbar);
        rootFrameLayout = (FrameLayout) findViewById(R.id.activity_media_player_root_layout);
        footerButtonLayout = (RelativeLayout) findViewById(R.id.activity_mediaplayer_footer_button_layout);

        footerButtonLayout.setVisibility(View.GONE);

        prevButton.setOnClickListener(this);
        playAndPauseButton.setOnClickListener(this);
        nextButton.setOnClickListener(this);
        surfaceHolder = playerSurfaceView.getHolder();
        surfaceHolder.addCallback(this);

        seekbar.setVisibility(View.INVISIBLE);

        rootFrameLayout.setOnTouchListener(new View.OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                if (event.getAction() == MotionEvent.ACTION_UP) {
                    seekbar.setVisibility(View.INVISIBLE);
                    if (!isFooterLayoutShow) {
                        isFooterLayoutShow = true;
                        footerButtonLayout.setVisibility(View.VISIBLE);
                    } else {
                        isFooterLayoutShow = false;
                        footerButtonLayout.setVisibility(View.INVISIBLE);
                    }
                } else {
                    seekbar.setVisibility(View.VISIBLE);
                }
                return true;
            }
        });

        //
        // showProgressDialog();
    }

    /**
     * Surface Holder Callback Methods
     */
    @Override
    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
        // TODO Auto-generated method stub

    }

    @Override
    public void surfaceCreated(SurfaceHolder arg0) {

        try {
            playMediaPlayer();
        } catch (IllegalArgumentException e) {
            // TODO Auto-generated catch block
            Utils.writeToSDCard("Exception -" + e.getMessage());
        } catch (SecurityException e) {
            // TODO Auto-generated catch block
            Utils.writeToSDCard("Exception -" + e.getMessage());
        } catch (IllegalStateException e) {
            // TODO Auto-generated catch block
            Utils.writeToSDCard("Exception -" + e.getMessage());
        }
    }

    /**
     * Method is used to play media file.
     */
    private void playMediaPlayer() {

        if (urls != null) {
            try {
                if (currentIndex < urls.size()) {

                    //
                    // showProgressDialog();

                    if (mediaPlayer == null) {
                        mediaPlayer = new MediaPlayer();
                    }

                    mediaPlayer.reset();
                    mediaPlayer.setDisplay(surfaceHolder);
                    /*
                     * System.out.println(" url :: " +
                     * urls.get(currentIndex).getUrl());
                     */
                    boolean a=MasterData.songtest;
                    /*if(MasterData.songtest){
                        mediaPlayer.setDataSource("http://122.165.94.246/rms/trans.mp4");

                    }else{*/
                    Log.e("print","for url :"+MasterData.songtest+urls.get(currentIndex).getUrl());
                    mediaPlayer.setDataSource(urls.get(currentIndex).getUrl());
                    /*}*/

                    showToast("Preparing media player");
                    //mediaPlayer.prepareAsync();
                    mediaPlayer.prepare();

                    mediaPlayer.setOnCompletionListener(this);
                    mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
                    mediaPlayer
                            .setOnBufferingUpdateListener(new OnBufferingUpdateListener() {

                                @Override
                                public void onBufferingUpdate(MediaPlayer mp,
                                        int percent) {
                                    // TODO Auto-generated method stub

                                    //
                                    // if(percent == 100){
                                    // stopProgressDialog();
                                    // }else {
                                    // showProgressDialog();
                                    // }
                                }
                            });

                    // ****************************************
                    mediaPlayer.setOnPreparedListener(new OnPreparedListener() {

                        @Override
                        public void onPrepared(MediaPlayer mp) {

                            /*
                             * if (progressDialog != null &&
                             * progressDialog.isShowing()) {
                             * progressDialog.dismiss(); }
                             */

                            seekbar.setMax(mediaPlayer.getDuration());
                            seekbar.postDelayed(onEverySecond, 1000);

                            mediaPlayer.start();
                            // stopProgressDialog();
                        }
                    });

                    onEverySecond = new Runnable() {

                        @Override
                        public void run() {

                            if (seekbar != null && mediaPlayer != null) {
                                seekbar.setProgress(mediaPlayer
                                        .getCurrentPosition());
                            }

                            if (mediaPlayer != null && mediaPlayer.isPlaying()) {
                                seekbar.postDelayed(onEverySecond, 1000);
                            }
                        }
                    };

                    seekbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

                        @Override
                        public void onStopTrackingTouch(SeekBar seekBar) {
                        }

                        @Override
                        public void onStartTrackingTouch(SeekBar seekBar) {
                        }

                        @Override
                        public void onProgressChanged(SeekBar seekBar,
                                int progress, boolean fromUser) {

                            if (fromUser) {
                                // this is when actually seekbar has been seeked
                                // to a new position
                                mediaPlayer.seekTo(progress);
                            }
                        }
                    });

                    // ***************************************

                } /*
                 * else { mediaPlayer.stop(); mediaPlayer.reset();
                 * playAndPauseButton.setBackgroundResource(R.drawable.stop); }
                 */
            } catch (IllegalStateException e) {

            } catch (Exception e) {

                Utils.writeToSDCard("Exception -" + e.getMessage());
                // showToast("Some error occured!");
                // stopProgressDialog();
            }
        } else {
            showToast("No urls list present.Download xml file");
            // stopProgressDialog();
            // finish();
            startActivity(new Intent(this, MainActivity.class));
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder arg0) {
        // TODO Auto-generated method stub
        if (mediaPlayer != null) {
            if (mediaPlayer.isPlaying())
                mediaPlayer.stop();
            mediaPlayer.reset();
        }
    }

    /**
     * Listner for Media File on Completion
     */
    @Override
    public void onCompletion(MediaPlayer mediaPlayer) {
        currentIndex++;
        progressDialog = null;
        playMediaPlayer();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (mediaPlayer != null) {
            mediaPlayer.stop();
            mediaPlayer.reset();
            mediaPlayer.release();
            mediaPlayer = null;
        }
    }

    /*@Override
    protected void onPause() {
        super.onPause();

    }*/

    /**
     * Method is used to controls all click event on view portion.
     */
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.activity_mediaplayer_next_btn:
            progressDialog = null;
            if (mediaPlayer != null) {
                playNextVideo();
            }
            break;
        case R.id.activity_mediaplayer_prev_btn:
            progressDialog = null;
            if (mediaPlayer != null) {
                playPrevVideo();
            }
            break;
        case R.id.activity_mediaplayer_play_and_pause_btn:
            playAndPauseVideo();
            break;

        default:
            break;
        }
    }

    /**
     * Method is used to play and pause media player based on click event.
     */
    private void playAndPauseVideo() {
        if (isPlayMode) {
            isPlayMode = false;
            playAndPauseButton.setBackgroundResource(R.drawable.play);
            if (mediaPlayer != null && mediaPlayer.isPlaying()) {
                mediaPlayer.pause();
            }
        } else {
            isPlayMode = true;
            playAndPauseButton.setBackgroundResource(R.drawable.pause);
            if (mediaPlayer != null) {
                mediaPlayer.start();
            }
        }
    }

    /**
     * Method is used to play previous video.
     */
    private void playPrevVideo() {
        if (currentIndex > 0) {
            //
            // showProgressDialog();
            currentIndex--;
            playMediaPlayer();
        } else {
            showToast("No Prev Video Present.");
        }

    }

    /**
     * Method is used to play next video.
     */
    private void playNextVideo() {
        if (currentIndex < urls.size() - 1) {
            //
            // showProgressDialog();
            currentIndex++;
            playMediaPlayer();
        } else {
            showToast("No Next Video Present.");

        }
    }

    /**
     * Method is used to show toast based on message param.
     * 
     * @param message
     */
    private void showToast(String message) {
        Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
    }

    /**
     * Method is used to show progress dialog.
     */
    private void showProgressDialog() {
        if (progressDialog == null) {
            progressDialog = ProgressDialog.show(this, "", "Buffering...");
        }
    }

    /**
     * Method is used to stop progress dialog.
     */
    private void stopProgressDialog() {
        if (progressDialog != null) {
            progressDialog.dismiss();
            progressDialog = null;
        }
    }

    @Override
    protected void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
        if (mediaPlayer != null) {
            mediaPlayer.stop();
            mediaPlayer.reset();
            mediaPlayer = null;
        }

    }

}