I'm building a GWT app where I want to be able to detect when a user releases a scroll bar on one of my ScrollPanels.

My use case is that the horizontal scroll bar represents time. Since it's impossible to represent the full range of scrollable time I want to just represent a small window of time with the scroll bar. When the user moves and releases the scroll bar I want to do a smooth recentering where the new center is the release point.

I can work out how to do this by building a custom scroll bar widget, but I wanted to check if I was missing some way to do it using a "native" scroll bar first.