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

[Francesco Fumanti <francesco fumanti gmx net>]

Hi,

Brian Cameron wrote:
> Francesco:
>
> First of all, great job!

Thanks.  :-)

> I think the docs/C/gdm.xml file needs some love to help improve
> the documentation to help people understand how to better customize
> autostart scripts and to make GDM work with different accessibility
> tools.  Would you be willing to provide some docs that go into more
> depth in explaining this?
>
> You could either provide a patch to the gdm.xml file, or if you provided
> the updated docs in ASCII format I could merge them into the gdm.xml
> file.

I wrote an improved version of the Accessibility Configuration section 
and attached it to a new bug that I filed against the documentation of GDM:
http://bugzilla.gnome.org/show_bug.cgi?id=590734

Usually, I use the XML editor from XMLMind to edit the xml file of 
mousetweaks, but I did not completely understand the structure it 
displayed for the gdm.xml file. Consequently, I choose to provide the 
improved version of the section in ascii format instead of messing up 
the current gdm.xml file.

Thanks for replacing the current version of the documentation of the 
Accessibility Configuration with my improved version if you find it 
appropriate. Do not hesitate to edit it the way you like. (I am assuming 
that the gdm.xml file contains the same documentation that is available 
on the following site: http://library.gnome.org/admin/gdm/2.26/ )

By the way, the current gdm.xml file of the git repo contains an error: 
the close tag (</p>) of the third paragraph counting from the bottom 
upwards is missing.


> > 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.)
>
> Yes, that is my understanding also.  It would be good if the
> "Configuration" section of the docs explained how this works better.

This should now be the case with my improved version of the section 
about the Accessibility Configuration.

> > 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.
>
> Perhaps it would be nice if GDM had both desktop files in the source
> and had a configure option which allowed you to specify which
> desktop file for on-screen-keyboard use to install when you built it?
> That way distros could easily choose which one to use.

In fact, it could be useful for distributions; but on the other hand, 
how would you like to determine which desktop files to include and which 
not?

Ubuntu for example ships onboard as default onscreen keyboard, but 
onboard is not an application that is part of the default GNOME desktop.


> > 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.
>
> Again, perhaps this could be made more clear in the "Configuration"
> section of the docs.
>
> > 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!?
>
> Correct.  Probably should be made more clear in the "Configuration"
> section of the docs.
>
> > 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?
>
> Yes, it sounds correct to me.
>
> > Once it has been confirmed to be correct, this howto could be added to 
> > the documentation as you suggested above.
>
> Perhaps a new section could be added as an appendix to the documentation
> to give an example of how to configure GDM to work with a different AT
> program.

I decided to put it all in the section of the Accessibility 
Configuration, also the example about how to replace and add an 
additional accessibility tool. I thought that it might be better having 
it all in one place.


> However, I also think it is important to update the "Configuration"
> section of the docs so that the way things work is more clearly
> described.
>
> > 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
>
> When I run gconf-editor using GNOME 2.26, I see these keys.
>
> > 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?
>
> I think this is a bug.  These keys are not used in the code, and
> probably should be removed from the schemas file.

By starting the gconf-editor with a desktop file along with the onscreen 
keyboard during GDM, I could verify that it is the first set of gconf 
keys that gets used by the new GDM. Maybe that the second set is some 
leftover from the old gdm and should indeed be removed during the 
installation of the new GDM.


> > 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
>
> That sounds like a neat feature.  

Does this mean that it would be accepted if somebody would write a 
corresponding patch or would it have to also pass other teams, for 
example the team responsible for the HIG?


> However, we still need a way for
> blind users to launch AT programs via a hotkey combination.

This is probably a really bad for the concerned users.



> > > > - 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.
>
> If you are using GDM 2.21 and later, you should not have these in your
> custom.conf file.  The new GDM does not support these modules anymore.
>
> If you are using the older GDM 2.20 or earlier, you should add these
> lines in the [daemon] section of the custom.conf file to enable a11y:
>
> AddGtkModules=true
> GtkModulesList=gail:atk-bridge:/usr/lib/gtk-2.0/modules/libdwellmouselistener:/ 
>
> usr/lib/gtk-2.0/modules/libkeymouselistener

Unless I made an error, I should have been using the new GDM at that 
time. In any case, this entries are not anymore available in the 
custom.conf file and I don't remember removing them manually. Maybe that 
it was fixed by one of the many GDM updates that hit in the Ubuntu repos.


Cheers,

Francesco