** You absolutely have got to sand the ceramic tile first! "Washing" or creating a clean surface, by itself will not work. Sure, it will look nice at first, however, you will see how the surface will begin to crack and peel and fall apart soon.
Use medium grit sandpaper to remove what causes the "shine" on the tile. Then make sure you clean the tile and complete area when you are done. THEN apply your primer as directed in these other posts. This extra effort will save you the time, labor and expense of removing the paint and doing it all over again.