Maps

Question

hi guys,

i have been trying to build a small program that works as a maps website - something like Google maps.
i am having trouble making it work properly, my problem is panning the map.
i am using a 5x5 grid, where only the middle 3x3 squares are visible, each one of them is 200x200 pxls.
also i have a huge map that is divided into squares of 200x200 pxls and named according to its coordinate.

i have a class that creates my an array of the needed 25 pictures, a methood that places them on the grid properly.
my thinking was when the user moves the grid more then 200 pixles to any side, the grid will RESET LOCATION back to its original position but load the next set of images.

well, for some reason this is not working properlly.
i need help, maybe even other idea - to change the way it should work :)

thnx guyz!