Image caching question

[Darrin Smith]

In my app I have two sets of images.

The top set is contolled by an upper listbox selection and the bottom set is controlled by a lower listbox selection.

The way I would like it to work is that when the user selects an item form the upper listbox, only the images in the top section are refreshed from the server, and when the bottom listbox is selected only the bottom set of images is refreshed from the server.

The way it works now is that both top and bottom image sets get refreshed from the server when either the upper or lower listbox item is changed.

I am thinking that there should be an easy way to cache the images so both sets do not need to be refreshed each time one of the listboxes gets changed.

I don't see any way to just keep an array of additional buttons they hold my images) around to fill up the buttons on the page as the setValue method takes a URL...not an actual image.

So, what is the suggested way to do this?