Re: when to bind *down-mouse* vs *mouse*?

[Alex Schroeder <alex@emacswiki.org>]

"Drew Adams" <drew.adams@oracle.com> writes:

> And these applications nevertheless let you keep the button pressed and
> release it on a menu item to choose the item. And they let you,
> alternatively, use separate clicks: one to bring up the menu, one to choose
> each submenu (if any), and one to choose a menu item.
>
> So, I would say that it is not clear that popup menus should be opened on
> down-mouse - the reasons given so far aren't convincing. I'm not saying that
> Emacs should necessarily behave like Windows apps; I'm just asking why it is
> a good idea to bind popup menu opening to down-mouse, rather than mouse
> (mouse-up).

Assume an environment where you can press mouse-down, and a popup-menu
appears.  Keeping the mouse button pressed, move to the menu entry you
want to pick and release the mouse button.  This kind of behaviour is
possible for some systems (eg. xman for X11).  Binding a menu to
mouse-up would make this menu unusable on these systems.  The menu
won't appear unless you release the mouse, but it will disappear as
soon as you release the mouse...  That's why I think we want
mouse-down for popups.

Alex.
-- 
.O.  http://www.emacswiki.org/alex/
..O  Schroeder's fifth law:
OOO  Never accept more work than you can handle in one night of hacking.