XML Photo Gallery X4

Okay, what if one wants to display a row of four images at a time.
And when the “Next” button is clicked, we see the 2nd, 3rd, 4th, and 5th image.
When we click the “Previous” button, we go back to the 1st through 4th.
We would be able to show any number of images like this.
How would something like this work? Complicated?
I look forward to hearing from you.
-pterodactyl