static void drawIntoBitmap (Bitmap bm)
{
float x = bm.getWidth ();
float y = bm.getHeight ();
Canvas c = new Canvas (bm);
Paint p = new Paint ();
p.setAntiAlias (true);
p.setAlpha (0x80);
c.drawCircle (x / 2, y / 2, x / 2, p);
p.setAlpha (0x30);
p.setXfermode (new PorterDuffXfermode (PorterDuff.Mode.SRC));
p.setTextSize (60);
p.setTextAlign (Paint.Align.CENTER);
Paint.FontMetrics fm = p.getFontMetrics ();
c.drawText ("Alpha", x / 2, (y - fm.ascent) / 2, p);
}