WM suport for grab key scrolling

[Eben Eliason]

On 4/20/07, Marco Pesenti Gritti <mpg at redhat.com> wrote:
> On Fri, 2007-04-20 at 18:27 +0200, Bert Freudenberg wrote:
> > > Well, yeah, but the fact that's physically part of the the keyboard
> > > doesn't really suggest it's a mouse modifier. And the fact that we
> > > have
> > > a scrolling mode (press/release) doesn't suggest it either.
> >
> > Who actually thinks this is a good idea? I'd much rather require
> > holding the grab key. There will be numerous kids trying to move the
> > pointer while nothing happens.

Yeah, When I first considered that idea I was still envisioning a
graphical change of the cursor to indicate the mode.  If we don't have
any visual indication that "scroll mode" is active, then we probably
shouldn't allow it to lock on.

The more I consider it, though, I think a cursor change is probably
the right thing to do anyway.  Highlighting the scrollbar is good, but
actually modifying the cursor really links the two logically.  Perhaps
we should use the "fleur" cursor when the view can scroll both
directions, and the "left-right" or "up/down" (whatever the correct
name is for those) cursors when the region scrolls only in one axis.
Perhaps better, we can duplicate the grab key graphic, smaller and
superimposed over the aforementioned icons.

This gives visual feedback that links the key to the cursor position.
It also let's you know (in addition to the highlighting) that a scroll
region accepts grab scrolling (since the cursor shouldn't change
unless it's in a region that supports it).  It also provides
additional information about the directions you can scroll.  These are
all good things.

We can still argue about the grab-lock mode independently of this.  I
won't cry if it doesn't get in.  I think I'd like it personally, but
it would really come down to user testing with kids in my opinion.

- Eben