The problem you are having could be a wide variety of issues. Without seeing your code it is very difficult to figure out what's going on. Instead, I'll try to explain what my game is doing to draw the tiles.
For rendering the world to the screen I have 4 classes: World, Level, Tile, and Map.
The Map class simple holds an array for each level. It's basically just the layout.
The Tile class represents a single tile, so mostly it just loads the right image. It also has its own draw method.
The Level class organizes the tiles based on the appropriate map and has it's own draw method, which simply calls draw on each tile in the level.
Finally, the World class keeps all the levels organized and calls the proper level's draw method when needed.
The code that you pasted here is the World class retrieving the appropriate level from the levels array, and calling that level's draw method. That method then just calls the draw method of each tile in that level.
I hope that I explained it well enough to help you figure out the bug you've got going on. If you want more in depth help, feel free to give us your code so we can look over it.
P.S. Glad I could help get you on the right track!