android播放器实现歌词显示功能

import android.os.Bundle; 
import android.os.Handler; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
 
public class TextAlign extends GraphicsActivity implements OnClickListener { 
 
  private SampleView mView; 
 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    // Animation in = AnimationUtils.loadAnimation(this, R.anim.push_up_in); 
 
    // mView.setAnimation(in); 
    setContentView(R.layout.main); 
    mView =(SampleView) findViewById(R.id.text01); 
 
    Button bt = (Button) findViewById(R.id.Button01); 
    bt.setOnClickListener(this); 
     
    new Thread(new UIUpdateThread()).start(); 
 
  } 
 
  class UIUpdateThread implements Runnable { 
    long time = 40000; 
 
    long sleeptime = 100; 
    public void run() { 
      try { 
        while (time < 200000) { 
          Thread.sleep(sleeptime); 
          mView.updateIndex(time);//.index = mLyric.getNowSentenceIndex(time); 
//         Log.v("UIThread", mView.index + ":" + time); 
          time += sleeptime; 
          mHandler.post(mUpdateResults); 
        } 
      } catch (InterruptedException e) { 
        e.printStackTrace(); 
      } 
    } 
  } 
  Handler mHandler = new Handler(); 
  Runnable mUpdateResults = new Runnable() { 
    public void run() { 
      mView.invalidate(); // 更新视图 
    } 
  }; 
 
  @Override 
  public void onClick(View v) { 
    mView.mTouchHistoryY -=30; 
    mHandler.post(mUpdateResults); 
  } 
} 

import java.io.File; 
import java.util.List; 
import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.graphics.Path; 
import android.graphics.Typeface; 
import android.util.AttributeSet; 
import android.util.Log; 
import android.view.MotionEvent; 
import android.widget.TextView; 
import android.widget.Toast; 
import com.android.lyric.Lyric; 
import com.android.lyric.PlayListItem; 
import com.android.lyric.Sentence; 
public class SampleView extends TextView { 
private Paint mPaint; 
private float mX; 
private static Lyric mLyric; 
private Path mPath; 
private Paint mPathPaint; 
public String test = "test"; 
public int index = 0; 
private List<Sentence  list; 
private float mTouchStartY; 
private float mTouchCurrY; 
public float mTouchHistoryY; 
private int mY; 
private long currentTime; 
private long currentDunringTime; 
private long sentenctTime; 
private float middleY; 
private String middleContent="Empty"; 
private static final int DY = 30; 
private static void makePath(Path p) { 
p.moveTo(10, 0); 
p.cubicTo(100, -50, 200, 50, 300, 0); 
} 
public SampleView(Context context) { 
super(context); 
init(); 
} 
public SampleView(Context context,AttributeSet attr) { 
super(context,attr); 
init(); 
} 
public SampleView(Context context,AttributeSet attr,int i) { 
super(context,attr,i); 
init(); 
} 
private void init() { 
setFocusable(true); 
PlayListItem pli = new PlayListItem("", "", 1000L, true); 
mLyric = new Lyric(new File("/sdcard/M0005044007.lrc"), pli); 
list = mLyric.list; 
mPaint = new Paint(); 
mPaint.setAntiAlias(true); 
mPaint.setTextSize(20); 
mPaint.setTypeface(Typeface.SERIF); 
mPath = new Path(); 
makePath(mPath); 
mPathPaint = new Paint(); 
mPathPaint.setAntiAlias(true); 
mPathPaint.setColor(0x800000FF); 
mPathPaint.setStyle(Paint.Style.STROKE); 
} 
@Override 
protected void onDraw(Canvas canvas) { 
super.onDraw(canvas); 
canvas.drawColor(Color.WHITE); 
Paint p = mPaint; 
float x = mX; 
float plus =currentDunringTime==0?index*30: index*30 +(((float)currentTime - (float)sentenctTime)/(float)currentDunringTime)*(float)30; 
float y = mY- plus+mTouchCurrY - mTouchStartY+mTouchHistoryY; 
canvas.translate(0,y); 
for (int i = 0; i < index; i++) { 
String text = list.get(i).getContent(); 
if((y+i*30)<=middleY&&(y+i*30+30) =middleY) 
middleContent = text; 
p.setTextAlign(Paint.Align.CENTER); 
canvas.drawText(text, x, 0, p); 
// mY- mY/lines*(index - i) 
canvas.translate(0, DY); 
} 
} 
@Override 
protected void onSizeChanged(int w, int h, int ow, int oh) { 
super.onSizeChanged(w, h, ow, oh); 
mX = w * 0.5f; // remember the center of the screen 
mY = h; 
middleY = h*0.5f; 
} 
@Override 
public boolean onTouchEvent(MotionEvent event) { 
float y = event.getY(); 
switch (event.getAction()) { 
case MotionEvent.ACTION_DOWN: 
mTouchHistoryY += mTouchCurrY - mTouchStartY; 
mTouchStartY =mTouchCurrY= y; 
invalidate(); 
break; 
case MotionEvent.ACTION_MOVE: 
mTouchCurrY = y; 
invalidate(); 
break; 
case MotionEvent.ACTION_UP: 
Log.v("Lyric content", middleContent.length()+""); 
CharSequence chars = new CharSequence(){ 
@Override 
public char charAt(int index) { 
// TODO Auto-generated method stub 
return middleContent.charAt(index); 
} 
@Override 
public int length() { 
// TODO Auto-generated method stub 
return middleContent.length(); 
} 
@Override 
public CharSequence subSequence(int start, int end) { 
// TODO Auto-generated method stub 
return middleContent.subSequence(start, end); 
} 
@Override 
public String toString(){ 
return middleContent; 
} 
}; 
Toast toast = Toast.makeText(SampleView.this.getContext(),chars, 1000); 
toast.show(); 
invalidate(); 
break; 
} 
return true; 
} 
public void updateIndex(long time) { 
this.currentTime = time; 
index = mLyric.getNowSentenceIndex(time); 
Sentence sen = list.get(index); 
currentDunringTime = sen.getDuring(); 
sentenctTime = sen.getFromTime(); 
} 
}