android实现音乐播放器进度条效果

<TextView  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:text="@string/hello" />   <EditText  android:id="@+id/mediaFileName"  android:layout_width="match_parent"  android:text="gangstabop.mp3"  android:layout_height="wrap_content" >  <requestFocus />  </EditText>    <LinearLayout  android:id="@+id/linearButton"  android:layout_width="match_parent"  android:layout_height="wrap_content" >   <Button   android:id="@+id/playButton"   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:text="@string/stop" />   <SeekBar   android:id="@+id/playSeekBar"   android:layout_width="140px"   android:layout_height="wrap_content"   android:layout_marginLeft="3px"   android:layout_marginTop="5px" />   <Button   android:id="@+id/replayButton"   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:layout_marginLeft="3px"   android:text="@string/replay" />  </LinearLayout>

/**  * @CreateDate 2015-2-3  * @Author hubiao  * @Title 音乐播放器  */ public class MediaActivity extends Activity {  private MediaPlayer mediaPlayer;//媒体播放器  private Button playButton;  private Button replayButton ;  private boolean isCellPlay;/*在挂断电话的时候，用于判断是否为是来电时中断*/  private boolean isSeekBarChanging;//互斥变量，防止进度条与定时器冲突。  private int currentPosition;//当前音乐播放的进度  private SeekBar seekBar;  private Timer timer;   private static final String TAG = "MediaActivity";   @Override  public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.main);   //实例化媒体播放器  mediaPlayer = new MediaPlayer();    //监听滚动条事件  seekBar = (SeekBar) findViewById(R.id.playSeekBar);  seekBar.setOnSeekBarChangeListener(new MySeekBar());    // 监听[播放或暂停]事件  playButton= (Button) findViewById(R.id.playButton);  playButton.setOnClickListener(new PalyListener());    //监听[重播]事件  replayButton= (Button) findViewById(R.id.replayButton);  replayButton.setOnClickListener(new OnClickListener() {   public void onClick(View v) {   mediaPlayer.reset();   currentPosition = 0;   play();   }  });    //监听来电事件  TelephonyManager phoneyMana = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);  phoneyMana.listen(new myPhoneStateListener(),PhoneStateListener.LISTEN_CALL_STATE);  }  /*销毁时释资源*/  @Override  protected void onDestroy() {  mediaPlayer.release();  timer.cancel();  timer = null;  mediaPlayer = null;  super.onDestroy();  }   /*播放或暂停事件处理*/  private class PalyListener implements OnClickListener {  public void onClick(View v) {   if(playButton.getText().toString().equals("播放"))   {   currentPosition = mediaPlayer.getCurrentPosition();//记录播放的位置   mediaPlayer.stop();//暂停状态   playButton.setText(R.string.stop);   timer.purge();//移除所有任务;   }   else{   mediaPlayer.reset();   play();   }  }  }   /*播放处理*/  private void play() {  File media = new File("/mnt/sdcard/files/","bewithyou.mp3");//由于是练习，就把mp3名称固定了  Log.i(TAG, media.getAbsolutePath());  if(media.exists())  {   try {   mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);//设置音频类型   mediaPlayer.setDataSource(media.getAbsolutePath());//设置mp3数据源   mediaPlayer.prepareAsync();//数据缓冲   /*监听缓存 事件，在缓冲完毕后，开始播放*/   mediaPlayer.setOnPreparedListener(new OnPreparedListener() {    public void onPrepared(MediaPlayer mp) {    mp.start();    mp.seekTo(currentPosition);    playButton.setText(R.string.play);    seekBar.setMax(mediaPlayer.getDuration());    }   });   //监听播放时回调函数   timer = new Timer();   timer.schedule(new TimerTask() {    @Override    public void run() {    if(!isSeekBarChanging){     seekBar.setProgress(mediaPlayer.getCurrentPosition());    }    }   },0,50);   } catch (Exception e) {   Toast.makeText(getApplicationContext(), R.string.playError, Toast.LENGTH_LONG).show();   e.printStackTrace();   System.out.println(e);   }  }  else{   Toast.makeText(getApplicationContext(), R.string.fileError, Toast.LENGTH_LONG).show();  }  }   /*来电事件处理*/  private class myPhoneStateListener extends PhoneStateListener  {  @Override  public void onCallStateChanged(int state, String incomingNumber) {  switch (state) {   case TelephonyManager.CALL_STATE_RINGING://来电，应当停止音乐   if(mediaPlayer.isPlaying() && playButton.getText().toString().equals("播放")){    currentPosition = mediaPlayer.getCurrentPosition();//记录播放的位置    mediaPlayer.stop();    isCellPlay = true;//标记这是属于来电时暂停的标记    playButton.setText(R.string.stop);    timer.purge();//移除定时器任务;   }   break;   case TelephonyManager.CALL_STATE_IDLE://无电话状态   if(isCellPlay){    isCellPlay = false;    mediaPlayer.reset();    play();   }   break;   }  }  }   /*进度条处理*/  public class MySeekBar implements OnSeekBarChangeListener{   public void onProgressChanged(SeekBar seekBar, int progress,   boolean fromUser) {  }   /*滚动时,应当暂停后台定时器*/  public void onStartTrackingTouch(SeekBar seekBar) {   isSeekBarChanging = true;  }  /*滑动结束后，重新设置值*/  public void onStopTrackingTouch(SeekBar seekBar) {   isSeekBarChanging = false;   mediaPlayer.seekTo(seekBar.getProgress());  }  } } 

<!-- 申请SD卡写入权限 --> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <!--申请SD卡创建与权限 --> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> <!-- 拦截号码权限 --> <uses-permission android:name="android.permission.READ_PHONE_STATE"/>