how to sort images in grid

hi i am new to iphone .what i did is displaying 20 images as grid using custom image picker and display them using imageview. here i treated every image as a button and display selected image using button tag value.now what i want is if i click any 4 images or a single image for 4 times that will be goes to end of the grid how can i done this pls help me if it possible po开发者_运维百科st some code thank u

Please look for Thee20 library