网络播放器

public class MainActivity extends Activity {
    private EditText nameText;
    private String path;
    private MediaPlayer mediaPlayer;
    private SurfaceView surfaceView;//此组件用于播放视频
    private boolean pause;
    private int position;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        mediaPlayer = new MediaPlayer();
        nameText = (EditText) this.findViewById(R.id.filename);
        surfaceView = (SurfaceView) this.findViewById(R.id.surfaceView);
        //把输送给surfaceView的视频画面，直接显示到屏幕上,不要维持它自身的缓冲区
        surfaceView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        surfaceView.getHolder().setFixedSize(176, 144);
        surfaceView.getHolder().setKeepScreenOn(true);
        //当SurfaceView所在的Activity离开了前台，SurfaceView会被destroy，当Activity 
        //重新回到前台时，SurfaceView会被重新创建，创建时在onresume()方法之后,所以此时会出现黑屏，使用下面的方法解决
        surfaceView.getHolder().addCallback(new SurfaceCallback());
    }
    
    private final class SurfaceCallback implements Callback{
        public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        }
        public void surfaceCreated(SurfaceHolder holder) {
            //重新播放
            if(position>0 && path!=null){
                play(position);
                position = 0;
            }
        }
        public void surfaceDestroyed(SurfaceHolder holder) {
            //停止播放
            if(mediaPlayer.isPlaying()){
                position = mediaPlayer.getCurrentPosition();
                mediaPlayer.stop();
            }
        }
    }

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

    public void mediaplay(View v){
        switch (v.getId()) {
        case R.id.playbutton://处理播放按钮点击事件
            String filename = nameText.getText().toString();
            if(filename.startsWith("http")){//播放网络媒体文件，注意网络文件要是流媒体文件才可以
                path = filename;
                play(0);
            }else{
                File file = new File(Environment.getExternalStorageDirectory(), filename);
                if(file.exists()){
                    path = file.getAbsolutePath();
                    play(0);
                }else{
                    path = null;
                    Toast.makeText(this, R.string.filenoexsit, 1).show();
                }
            }
        
            break;

        case R.id.pausebutton://处理暂停按钮点击事件
            if(mediaPlayer.isPlaying()){
                mediaPlayer.pause();
                pause = true;
            }else{
                if(pause){
                    mediaPlayer.start();
                    pause = false;
                }
            }
            break;
            
        case R.id.resetbutton://处理重新播放按钮点击事件
            if(mediaPlayer.isPlaying()){
                mediaPlayer.seekTo(0);
            }else{
                if(path!=null){
                    play(0);
                }
            }
            break;
        case R.id.stopbutton:
            if(mediaPlayer.isPlaying()){
                mediaPlayer.stop();
            }
            break;
        }
    }

    private void play(int position) { //播放视频的方法
        try {
            mediaPlayer.reset();
            mediaPlayer.setDataSource(path);//设置数据源
            mediaPlayer.setDisplay(surfaceView.getHolder());//设置SurfaceView的控对象
            mediaPlayer.prepare();//缓冲
            mediaPlayer.setOnPreparedListener(new PrepareListener(position));//设置缓冲监听对象，在监听对象中进行播放
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    //当缓冲完毕后会调用onPrepared()方法
    private final class PrepareListener implements OnPreparedListener{
        private int position;
        
        public PrepareListener(int position) {
             this.position = position;
        }

        public void onPrepared(MediaPlayer mp) {
            mediaPlayer.start();//播放视频
            if(position>0) mediaPlayer.seekTo(position);
        }
    }
}