rotate image in android apps

i guess i'm starting to learn a thing or two about organizing my stuff, and as result decided to post the result of one task that is a part of a bigger task, that is a part of an idea that i'm already getting tired of chasing...

my app has to display images and i want to be able to rotate them! sounds simple, and it is! especially with the miracle of Internet, GOOG and stackoverflow.com

so we have this imageview...
  ImageView imageView = (ImageView) findViewById(R.id.test_image1);

we're loading some picture onto it...
 Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);

and turns out there is this lovely Matrix class, that exists for all kind of math abuses
                 Matrix mat = new Matrix();
                 mat.postRotate(gradus);

so we can take the original bitmap and apply the matrix operation on it
                  Bitmap bMapRotate = Bitmap.createBitmap(bMap, 0, 0, bMap.getWidth(), bMap.getHeight(), mat, true);

and when we set this image on the imageView we expect to see the rotated image, right?
                imageView.setImageBitmap(bMapRotate);

but somewhere something is wrong or some manual has not been read, cause a vital piece is missing: you have to set scale type on the imageView, (before assigning the new image?)
              imageView.setScaleType(ScaleType.MATRIX);

now this will work fine and will leave this highly uninformative post online, so i can remember how i did it!

i simply don't have the time to research the why's and do's - at least not right now that i'm still in prototyping phase and the steam has already began to ...steam away...
i lost a few days (all right - couple of hours over few days) with the rotate images problem and at least it made me learn to split bigger tasks into smaller ones - and how effective and helpful it can be!