private static void rotateTextView(final TextView textView) {
        //measure normal text width
        textView.setRotation(0);
        textView.measure(0, 0);
        final int width = textView.getMeasuredWidth();
        textView.setRotation(-90);
        textView.setTranslationX((float) -(width - ViewUtils.spToPixel(14)) / 2);
        textView.requestLayout();
    }
returns actual matrix data. Do not change the returned array, it is for reading only!
main/src/main/java/cgeo/geocaching/ui/CheckboxMatrixView.java