Re: [gdm-list] questions about the mobility a11y in gdm 2.26 in Ubuntu

[Francesco Fumanti <francesco fumanti gmx net>]

Hi Brian,


First of all, thanks for your reply.


Brian Cameron wrote:
> > GDM 2.26 has arrived in the development version of Ubuntu 9.10
> > (Ubuntu karmic) and I have a few questions:
> >
> > - Currently, when I enable the onscreen keyboard, gok appears on
> > the screen. Is there any configuration file, where I can replace
> > gok by another onscreen keyboard?
>
> Some information about configuring acessibility is here:
>
> http://library.gnome.org/admin/gdm/2.26/configuration.html.en#accessibilityconfiguration
>
>
>
> I believe that GDM will simply launch whatever is the "Preferred 
> Application" for the "gdm" user for magnifier, on-screen keyboard, or
>  screen reader.  So you would likely need to modify the "gdm" user's 
> $HOME GConf configuration to specify this.
>
> I don't know the keys off the top of my head, but if you get this 
> working it would be handy if you could do a write-up of what you 
> changed.  Then we could add this sort of information to the docs.

Here is how I got it working:

I have put an onboard.desktop file into the following directory:
/usr/share/gdm/autostart/LoginWindow/
(I am using Ubuntu 9.10 alpha; I don't know whether this directory can
be different on other distributions.)

And here is the content of onboard.desktop:
[code]
#!/usr/bin/env xdg-open
[Desktop Entry]
Encoding=UTF-8
Name=Onboard Onscreen Keyboard
Comment=Use an onscreen keyboard
TryExec=onboard
Exec=onboard
Terminal=false
Type=Application
StartupNotify=true
Categories=GNOME;GTK;Accessibility;
AutostartCondition=GNOME
/desktop/gnome/applications/at/screen_keyboard_enabled
X-Ubuntu-Gettext-Domain=gdm
[/code]

Of course, the tags [code] and [/code] are not in onboard.desktop.


It seems to work like this (I don't know however, whether I am guessing
right):

When a user activates the "Use onscreen keyboard" in the accessibility
dialog of GDM, the directory /usr/share/gdm/autostart/LoginWindow/ is
scanned and every desktop file that contains the following key in a line:

AutostartCondition=GNOME
/desktop/gnome/applications/at/screen_keyboard_enabled

gets executed. (If you see 2 lines above, then the email application
inserted a line break.)

Remark that every desktop file with containing that line gets started;
so it is possible to associate more than one application to the "Use
onscreen keyboard" item of the accessibility dialog. As I did not want
to have onboard and gok to be started simultaneously, I had to delete or
rename the gok.desktop file to anything that does not end in .desktop
file; that way gok does not get started anymore.



Two other keys are available:

AutostartCondition=GNOME
/desktop/gnome/applications/at/screen_magnifier_enabled

AutostartCondition=GNOME
/desktop/gnome/applications/at/screen_reader_enabled

which correspond respectively to the magnifier and screenreader items of
the accessibility dialog of GDM.

I suppose that the other items in the accessibility dialog do not have
corresponding keys because these features are provided directly by the X
server that does not need to get started as it is already running!?



Thanks to Gerd K. for helping me setup onboard as a replacement of gok.
As I am using it, I know that it works (at least in the Ubuntu 9.10
development version); but can anybody with the appropriate knowledge
tell me whether the explanation I gave here above is right or correct
what is wrong?


Once it has been confirmed to be correct, this howto could be added to 
the documentation as you suggested above.



There is however something that is puzzling to me: when I open the
gconf-editor after having logged in into my GNOME session, I can't
find the keys:
/desktop/gnome/applications/at/screen_keyboard_enabled
/desktop/gnome/applications/at/screen_magnifier_enabled
/desktop/gnome/applications/at/screen_reader_enabled
But these 3 keys are available:
/apps/gdm/simple-greeter/accessibility/screen_keyboard_enabled
/apps/gdm/simple-greeter/accessibility/screen_magnifier_enabled
/apps/gdm/simple-greeter/accessibility/screen_reader_enabled

As far as I know, GDM runs under the "GDM" user and not under my
username and consequently uses a different gconf database. But I
nevertheless wonder whether these two sets of keys are somehow
related?


> > - Is the dialog, where the user can choose the accessibility tool 
> > configurable? Particularly, is it for example possible to add more
> >  items to it by editing a configuration file?
>
> I don't believe this is currently available.  It would be a good 
> enhancement, though.
>
> > - In the EaseOfAccess page on GNOME Live, there is also talk about
> >  dwell clicking: http://live.gnome.org/GDM/EaseOfAccess. As there 
> > currently is not a "Software Click" item in the a11y dialog, I
> > wonder whether it still has to be implemented?
>
> I believe you can use mousetweaks for dwell clicking.  It would be
> good to enhance GDM to make it easier for users to access this.
>
> http://projects.gnome.org/accessibility/screencasts.html

In the meantime, a person not needing dwelling can set up a
configuration for a dwell user by creating a desktop file,
- that is connected to one of the keys above
- that starts mousetweaks in dwell mode (mousetweaks is the application
providing the dwelling feature)
- that gets saved in /usr/share/gdm/autostart/LoginWindow/

The item in the accessibility dialog of GDM corresponding to the key
that starts mousetweaks has to remain always activated, as a dwell user
will not be able to reactivate dwelling by himself, once dwelling has
been turned of.


I filed a bug against GDM with an explanation about how to enhance
GDM so that, out-of-the-box, a dwell user can by himself activate
and use dwelling:
http://bugzilla.gnome.org/show_bug.cgi?id=589906




> > - In GDM 2.22, there was gdmsetup to configure GDM. Is there
> > anything similar in GDM 2.26?
>
> No, there are some efforts currently to address this.
>
> http://bugzilla.gnome.org/show_bug.cgi?id=553250
>
> > - I have seen that "dwellmouselistener" is called in 
> > /etc/gdm/custom.conf. Does it mean that the accessibility tools can
> > be started by mouse gestures in GDM 2.26 as it was the case in GDM
> > 2.22? If so, could you please tell me in what file the gestures are
> > defined for GDM 2.26?
>
> GDM 2.20 and earlier supported this.  The new GDM does not provide
> any mechanism for users to launch AT programs except via the dialog.
> It would be good to enhance both GDM and the normal GNOME user
> session to support this sort of feature.  Some people have suggested
> it would be best to implement this in gnome-settings-daemon so it
> would work consistently in GDM and a normal GNOME user session.

I probably messed up things last time: I don't see anymore 
"dwellmouselistener" in /etc/gdm/custom.conf.


> > Maybe there is already some documentation available for GDM 2.26 
> > addressing the questions above.
>
> The docs are here:
>
> http://library.gnome.org/admin/gdm/2.26/

Thanks for the link.


Cheers,

Francesco