Re: Why can't we scroll the window with the middle button?

From: Michael G. Schneider <mgs_at_mgs-software.de>
Date: Sun, 4 Nov 2001 11:33:15 +0100
Message-ID: <9s34sf$tlp$00$1@news.t-online.com>

"Dino Hsu" <dino1_at_ms1.hinet.net> schrieb im Newsbeitrag news:c48a8333.0111031732.6efae48_at_posting.google.com...

> There is a scroller middle button on most new mouse models, with which
> we can scroll the window vertically without moving the mouse to the
> vertical scroll bar.
> Anyone knows how this button works? Microsoft has been notorious about
> not fully supporting java standards, is it possible for java programs
> like DBA Studio or Universal Installer to do this, from a developer's
> point of view?

Supporting the middle button, most of the time it is called the mouse wheel, is a very easy task. It is supported by the MS Windows User Interface API. As with anything happening to a window (being opend, being closed, scrollbar dragged, ...) this wheel is supported by a message sent to the window and handled by its window procedure. Specifically it is the WM_MOUSEWHEEL message.

Sorry I do not know Java that good. But I suspect in Java you also have some type of message pumping. I further suspect that you for example react on a WM_VSCROLL message, if the scrollbar has been used. If so, reacting on WM_MOUSEWHEEL should be simple.

Michael G. Schneider Received on Sun Nov 04 2001 - 04:33:15 CST