Libinput ScrollButton "Toggle"

[Paul Ewing]

Thanks for the explanation Peter, that makes sense! I've submitted an RFE as an
issue on the repository:

https://gitlab.freedesktop.org/libinput/libinput/issues/254

It's my first RFE so hopefully this process is correct; I only see instructions
in the README for bug reports.

Thanks again,
Paul

On Sun, Mar 17, 2019, at 3:43 PM, Peter Hutterer wrote:
> On Sat, Mar 16, 2019 at 09:17:20PM -0400, Paul Ewing wrote:
> > Hello,
> > 
> > I have a question regarding the "ScrollButton" option in libinput. I recently
> > purchased a trackball and I'd like to be able to configure it such that I can
> > press the button that I've set as the ScrollButton and then use the ball for
> > scrolling purposes. However, due to dexterity problems in my hand, I would
> > prefer not to hold the button down.
> > 
> > I've tried to use the DragLockButtons option to take care of logically locking
> > the button I've assigned as the ScrollButton but it doesn't seem to work. This
> > is what my configuration currently looks like:
> > 
> > # /usr/share/X11/99-trackball.conf
> > Section "InputClass"
> >     Identifier      "Elecom DEFT Pro Trackball"
> >     MatchProduct    "DEFT Pro TrackBall"
> >     Driver          "libinput"
> >     Option          "DragLockButtons" "10 10"
> >     Option          "ScrollButton" "10"
> >     Option          "ScrollMethod" "button"
> > EndSection
> > 
> > If I hold button 10, I can scroll; however, it doesn't lock when I press it.
> > Can anyone confirm if the functionality I'm trying to get is possible or if my
> > configuration has any glaring issues? 
> 
> it's not implemented yet, please file an RFE for libinput for this.
> 
> The technical reason in this case: button scrolling is a libinput feature,
> draglock is a feature implemented in the xorg driver. so by the time the
> drag lock for button 10 activates, libinput is already done with that
> button.
> 
> Cheers,
>    Peter
>