简易视频播放器的制作

package com.example.videoplayer;

import java.io.FileDescriptor;
import android.app.Activity;
import android.content.res.AssetFileDescriptor;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnBufferingUpdateListener;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class VideoPlayer extends Activity implements SurfaceHolder.Callback,
		OnBufferingUpdateListener, OnCompletionListener, OnPreparedListener {
	private static final String TAG = "VideoPlayer";
	private SurfaceView mSurfaceView;
    private SurfaceHolder mSurfaceHolder;
    private MediaPlayer mMediaPlayer;
    
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		mSurfaceView = new SurfaceView(this);
		mSurfaceHolder = mSurfaceView.getHolder();
		mSurfaceHolder.addCallback(this);

		//类型必须设置成SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS
        this.mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);    
		setContentView(mSurfaceView);
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.video_player, menu);
		return true;
	}

	@Override
	public void surfaceChanged(SurfaceHolder holder, int format, int width,
			int height) {
		Log.v(TAG, "surfaceChanged");
		
	}

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
		Log.v(TAG, "surfaceCreated");
		//SurfaceCreated 创建成功才可以播放视频
        PlayVideo();
	}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
		// TODO Auto-generated method stub
		Log.v(TAG, "surfaceDestroyed");
	}

	@Override
	public void onBufferingUpdate(MediaPlayer arg0, int arg1) {
		// TODO Auto-generated method stub
		Log.v(TAG, "onBufferingUpdate");
	}

	@Override
	public void onCompletion(MediaPlayer arg0) {
		// TODO Auto-generated method stub
		Log.v(TAG, "onCompletion");
	}

	@Override
	public void onPrepared(MediaPlayer mp) {
		// TODO Auto-generated method stub
		Log.v(TAG, "onPrepared");
	}

	public void PlayVideo(){
		Log.v(TAG, "PlayVideo");
        try {
            //视频文件放在 assert中
            AssetFileDescriptor aFD = this.getAssets().openFd("welcome.3gp");
            FileDescriptor fileDescriptor = aFD.getFileDescriptor();
            this.mMediaPlayer = new MediaPlayer();
            this.mMediaPlayer.setDataSource(fileDescriptor, aFD.getStartOffset(), aFD.getLength());
            aFD.close();    
            
            //视频放在SDCard中
            //File sdFile = Environment.getExternalStorageDirectory();
            //this.mMediaPlayer = new mMediaPlayer();
            //this.mMediaPlayer.setDataSource(sdFile.getAbsoluteFile() + File.separator + "welcome.3gp");
            
            //视频放在res中
            //this.mMediaPlayer = mMediaPlayer.create(this, R.raw.welcome);
            
            //网上的视频,没有测试
            //this.mMediaPlayer
            //    .setDataSource("http://xy2.163.com/download/down/wukong.mp3");
            
            this.mMediaPlayer.setDisplay(this.mSurfaceHolder);
            this.mMediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
            //准备完成后才可以播放,另外如果文件特别大或者从网上获得的资源
            //会在这里等待时间过长,造成堵塞,这样的话就得用
            //this.mMediaPlayer.prepareAsync(),然后监听是否准备完毕在开始
            
            this.mMediaPlayer.prepare();            
            this.mMediaPlayer.start();                
                
        } catch (Exception e) {
            // TODO: handle exception
        }
    }

	@Override
	protected void onDestroy() {
		// TODO Auto-generated method stub
		super.onDestroy();
		if (this.mMediaPlayer != null) {
            this.mMediaPlayer.release();
            this.mMediaPlayer = null;
        }
	}
	
	
}