Android图片重叠效果

把图片转换成为Bitmap对象，然后通过Canvas一层一层的画上去，当然Bitmap对象可以进行图片旋转、图片缩放等功能。
private Bitmap drawPicture(Bitmap mbitmap)
 {
   Bitmap bitmap=mbitmap;
    //BitmapFactory.decodeResource(getResources(), R.drawable.mymoive_01);     
        Bitmap mBitmap=Bitmap.createBitmap(bitmap.getWidth()+4,bitmap.getHeight()+4,Bitmap.Config.ARGB_8888);
        Canvas mCanvas =new Canvas(mBitmap);
        Paint mPaint=new Paint();
        
        mPaint.setColor(Color.WHITE);
        mCanvas.drawRect(0, 0, bitmap.getWidth()+4, bitmap.getHeight()+4, mPaint);
        mCanvas.drawBitmap(bitmap, 2, 2, new Paint());
        mCanvas.save(Canvas.ALL_SAVE_FLAG);
        mCanvas.restore();
        
        Matrix matrix=new Matrix();
        matrix.setRotate(8);
        Bitmap newBitmap=Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(),matrix,true);
        matrix.setRotate(5);
        Bitmap xBitmap =Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(),matrix,true);
        
        Canvas canvas = new Canvas(newBitmap);
        canvas.drawBitmap(xBitmap,0 ,0,new Paint());
        canvas.drawBitmap(mBitmap,0 ,4,new Paint());
        canvas.drawBitmap(mBitmap,0 ,10,new Paint());
        canvas.save(Canvas.ALL_SAVE_FLAG);
        canvas.restore();
        String filename="/sdcard/12.png";
        File file=new File(filename);
        
        FileOutputStream out;
  try {
   file.createNewFile();
   out = new FileOutputStream(file);
   newBitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
   Log.e("System.out", "Save Ok");
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   Log.e("System.out", e.toString());
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   Log.e("System.out", e.toString());
   e.printStackTrace();
  }
       

        
        return newBitmap;
 }