<br><br><div class="gmail_quote">On Wed, Jul 28, 2010 at 18:21, Laurent <span dir="ltr"><<a href="mailto:laurent.orseau@gmail.com">laurent.orseau@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> Hi,<br><br>I can see there are scroll events and an `on-scroll' method for canvas%, but not for list-box% or list-control%.<br>Is there a way to know when a scrollbar is moved in a list-box%?<br> <br>I need this to synchronize the scrolling of several list-boxes.<br><br></blockquote><div><br>Oops, this one is clearly explained in the docs at set-first-visible-item:<br><br><blockquote style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;" class="gmail_quote"> A program cannot detect when the scroll position changes except by polling <span class="RktSym"><a href="file:///usr/plt-5.0.1.1/doc/gui/list-box_.html?q=vertical-panel%25#%28meth._%28%28%28lib._mred/main..rkt%29._list-box%7E25%29._get-first-visible-item%29%29" class="RktValLink">get-first-visible-item</a></span>. <br> </blockquote><div><br> <br>Sorry.<br></div></div></div>