我遇到了一个我无法解决的问题.我正在使用MediaPlayer类来播放视频;但是,我总是失去原有的宽高比.这里提到了媒体播放器代码和xml代码.我尝试了很多东西,但仍然无法解决问题.我需要保持原始的宽高比.我已经在

Android Manifest文件中将此活动声明为全屏.我还在媒体播放器代码之后附加了xml代码.请建议我.

private class ErrorListener implements OnErrorListener {

// FIXME: @Override

public boolean onError(MediaPlayer mp, int what, int extra) {

String message = "Unknown error";

switch (what) {

case MediaPlayer.MEDIA_ERROR_UNKNOWN:

message = "Unable to play media";

showError(message);

break;

case MediaPlayer.MEDIA_ERROR_SERVER_DIED:

message = "Server failed";

showError(message);

break;

case MediaPlayer.MEDIA_ERROR_NOT_VALID_FOR_PROGRESSIVE_PLAYBACK:

message = "Invalid media";

showError(message);

break;

}

return false;

}

}

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

setContentView(R.layout.videoview);

Intent intent = getIntent();

uri = intent.getData();

new loadMovie().execute();

mPreview = (SurfaceView) findViewById(R.id.videoview);

mPreview.bringToFront();

holder = mPreview.getHolder();

holder.addCallback(this);

holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

mediaPlayer = new MediaPlayer();

}// onCreate Method Ends

private void playVideo() {

doCleanUp();

try {

mediaPlayer.setDataSource(this, uri);

} catch (IllegalArgumentException e) {

e.printStackTrace();

} catch (SecurityException e) {

e.printStackTrace();

} catch (IllegalStateException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

mediaPlayer.setDisplay(holder);

try {

mediaPlayer.prepare();

} catch (IllegalStateException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

mediaPlayer.setOnErrorListener(new ErrorListener());

mediaPlayer.setOnBufferingUpdateListener(this);

mediaPlayer.setOnCompletionListener(this);

mediaPlayer.setOnPreparedListener(this);

mediaPlayer.setOnVideoSizeChangedListener(this);

mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

mediaController = new MediaController(this);

}

@Override

public boolean onTouchEvent(MotionEvent event) {

mediaController.show();

return false;

}

// --MediaPlayerControl

// methods----------------------------------------------------

public void start() {

mediaPlayer.start();

}

public void pause() {

mediaPlayer.pause();

}

public int getDuration() {

return mediaPlayer.getDuration();

}

public int getCurrentPosition() {

return mediaPlayer.getCurrentPosition();

}

public void seekTo(int i) {

mediaPlayer.seekTo(i);

}

public boolean isPlaying() {

return mediaPlayer.isPlaying();

}

public int getBufferPercentage() {

return 0;

}

public boolean canPause() {

return true;

}

public boolean canSeekBackward() {

return true;

}

public boolean canSeekForward() {

return true;

}

// End of MediaPlayer

// Controls--------------------------------------------------------

// ------------------------

public void onPrepared(MediaPlayer mediaPlayer) {

mediaController.setMediaPlayer(this);

mediaController.setAnchorView(findViewById(R.id.videoview));

mIsVideoReadyToBePlayed = true;

if (mIsVideoReadyToBePlayed && mIsVideoSizeKnown) {

startVideoPlayback();

}

handler.post(new Runnable() {

public void run() {

mediaController.setEnabled(true);

mediaController.show();

}

});

}

public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {

// TODO Auto-generated method stub

}

public void surfaceCreated(SurfaceHolder holder) {

// TODO Auto-generated method stub

playVideo();

}

public void surfaceDestroyed(SurfaceHolder arg0) {

}

private void startVideoPlayback() {

holder.setFixedSize(mVideoWidth, mVideoHeight);

mediaPlayer.start();

}

public void onVideoSizeChanged(MediaPlayer mp, int width, int height) {

if (width == 0 || height == 0) {

return;

}

mIsVideoSizeKnown = true;

mVideoWidth = width;

mVideoHeight = height;

if (mIsVideoReadyToBePlayed && mIsVideoSizeKnown) {

startVideoPlayback();

}

}

public void onCompletion(MediaPlayer arg0) {

}

public void onBufferingUpdate(MediaPlayer mp, int percent) {

}

private void releaseMediaPlayer() {

mediaPlayer.release();

mediaPlayer = null;

}

private void doCleanUp() {

mVideoWidth = 0;

mVideoHeight = 0;

mIsVideoReadyToBePlayed = false;

mIsVideoSizeKnown = false;

}

这是XML：

android:orientation="horizontal"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:gravity="center"

>

android:layout_width="wrap_content"

android:layout_height="wrap_content"

/>

任何人都可以告诉我如何保持视频的宽高比？