在Bitmap上绘制Bitmap

///////////----------------必须复制出来，或者新建一个Bitmap，否则报错，原因是不能修改资源

 

public void Ondraw() {

  Bitmap bitt = Bitmap.createBitmap(bit1.getWidth(), bit1.getHeight(), bit1.getConfig());
  Canvas c1 = new Canvas(bitt);
  //c1.drawBitmap(bit1, 0f, 0f, null);
  c1.drawBitmap(bit2, 50f, 0f, null);
  c1.drawBitmap(bit3, 0f, 50f, null);

  Canvas c = holder.lockCanvas();

  c.drawBitmap(bitt, 0f, 0f, null);

  holder.unlockCanvasAndPost(c);
 }