From what you explained, it seems as though you need to tell whatever is being scrolled to adjust its position such that the top is in the viewing area after a new symbol is added. I don't see where it would involve your scroll controls, just the position of what's being scrolled.
I'm a little curious. You seem to be saying that as new images are selected, they are added to whatever else has already been selected, thus the reason for scrolling to see things. Why don't you just display the selected image and remove whatever precedes it so that there's no need to scroll?
Thanks for your reply. I'll try to explain it better. I have a long, vertically scrolling movie clip. This movie clip contains lots of thumbnails. When I click a thumbnail, the full sized image is loaded from the library and displayed within the same movie clip. when I click the full size movie clip, it disappears again, and I can click another thumbnail to display another full size image. So I'm not just adding more and more stuff to the gallery if that's what you were thinking. I'm just clicking thumbnails to display the full size image so I can look at it, closing it, and moving on.
But the full sized image is fixed at the very top of the scrolling movie clip, so if I click a thumbnail at the very bottom, I have to scroll all the way back up to the top to see the full size image. I just want the full size image to appear on screen no matter how far down I have scrolled to click a thumbnail.
I made my basic gallery useing this tutorial:
if you want to take a look at that, to get an idea of what I'm talking about.
Now I'm just trying to add some scrolling functionality, which wasn't included, but I don't really understand actionscript well enough to do this easily on my own.
Sorry for the long reply. I hope this is clearer.
Add the large image to a separate movieclip that is fixed to a position on the stage instead of the thumbnail one.