安卓两张片融合成一张片,android 两张片叠放

private Bitmap mergeBitmap(Bitmap firstBitmap, Bitmap secondBitmap) {        Bitmap bitmap = Bitmap.createBitmap(firstBitmap.getWidth(), firstBitmap.getHeight(),                firstBitmap.getConfig());        Canvas canvas = new Canvas(bitmap);        canvas.drawBitmap(firstBitmap, new Matrix(), null);        canvas.drawBitmap(secondBitmap, 0, 0, null);        return bitmap;}