Re: [Qemu-devel] [PATCH 0/8] Add GTK UI to enable basic accessibility (v2)

[Kevin Wolf]

Am 27.02.2012 15:39, schrieb Anthony Liguori:
> On 02/27/2012 08:24 AM, Kevin Wolf wrote:
>> Am 27.02.2012 00:46, schrieb Anthony Liguori:
>>> I realize UIs are the third rail of QEMU development, but over the years 
>>> I've
>>> gotten a lot of feedback from users about our UI.  I think everyone 
>>> struggles
>>> with the SDL interface and its lack of discoverability but it's worse than I
>>> think most people realize for users that rely on accessibility tools.
>>>
>>> The two pieces of feedback I've gotten the most re: accessibility are the 
>>> lack
>>> of QEMU's enablement for screen readers and the lack of configurable
>>> accelerators.
>>>
>>> Since we render our own terminal using a fixed sized font, we don't respect
>>> system font settings which means we ignore if the user has configured large
>>> print.
>>>
>>> We also don't integrate at all with screen readers which means that for 
>>> blind
>>> users, the virtual consoles may as well not even exist.
>>>
>>> We also don't allow any type of configuration of accelerators.  For users 
>>> with
>>> limited dexterity (this is actually more common than you would think), they 
>>> may
>>> use an input device that only inputs one key at a time.  Holding down two 
>>> keys
>>> at once is not possible for these users.
>>>
>>> These are solved problems though and while we could reinvent all of this
>>> ourselves with SDL, we would be crazy if we did.  Modern toolkits, like GTK,
>>> solve these problems.
>>>
>>> By using GTK, we can leverage VteTerminal for screen reader integration and 
>>> font
>>> configuration.  We can also use GTK's accelerator support to make 
>>> accelerators
>>> configurable (Gnome provides a global accelerator configuration interface).
>>>
>>> I'm not attempting to make a pretty desktop virtualization UI.  Maybe we'll 
>>> go
>>> there eventually but that's not what this series is about.
>>>
>>> This is just attempting to use a richer toolkit such that we can enable 
>>> basic
>>> accessibility support.  As a consequence, the UI is much more usable even 
>>> for a
>>> user without accessibility requirements so it's a win-win.
>>>
>>> Also available at:
>>>
>>> https://github.com/aliguori/qemu/tree/gtk.2
>>>
>>> ---
>>> v1 ->  v2
>>>   - Add internationalization support.  I don't actually speak any other 
>>> languages
>>>     so I added a placeholder for a German translation.  This can be tested 
>>> with
>>>     LANGUAGE=de_DE.UTF-8 qemu-system-x86_64
>>
>> Looks like I need to 'make install' before I can use the translations? I
>> don't have any qemu version installed into the system, but always run it
>> from to build directory (I would only confuse the different trees if
>> something was installed). Shouldn't it be possible that qemu finds the
>> right files just like it does with the BIOS etc.?
> 
> It's a little harder because of the way gettext works.  You can only have a 
> single search path AFAICT.
> 
> We could add a --with-localedir= to configure and then rearrange the po/ 
> structure.  Then you would do something like:
> 
> ./configure --with-localedir=$(pwd)/po
> 
> And it would use translations from your build directory.

Yeah, would be better than nothing.

>>>   - Fixed the terminal size for VteTerminal widgets.  I think the behavior 
>>> makes
>>>     sense now.
>>>   - Fixed lots of issues raised in review comments (see individual patches)
>>>
>>> Known Issues:
>>>   - I saw the X crash once.  I think it has to do with widget sizes.  I 
>>> need to
>>>     work harder to reproduce.
>>>   - I've not recreated the reported memory leak yet.
>>>   - I haven't added backwards compatibility code for older VteTerminal 
>>> widgets
>>>     yet.
>>
>> - F10 still activates the menu (same for Alt-F/V)
> 
> This is expected behavior although Grab on Hover will cause it to behave like 
> SDL does.

At least grabbing the keyboard manually with Ctrl-Alt-G doesn't disable
the accelerators, so even then you can't use these keys inside the VM.

> F10/Alt-F/V are menu accelerators and we need to allow menu accelerators for 
> things like Ctrl-Alt-2 to work.
> 
> More importantly, it should be possible to navigate the GUI without a mouse 
> (this is an accessibility requirement).  Without supporting Alt-F, there's no 
> way to navigate the menu from the keyboard.
> 
> That said, we probably do want to add a Send Key menu for sending key 
> sequences 
> that are used as accelerators.

Probably. But not for things as common as Alt-F, Alt-V or F10. Having to
use sendkey or the menus for these would be ridiculous and make SDL the
friendlier user interface again.

Can accelerators only be enabled or disabled all at once? Or could we
say that we disable everything that doesn't include Ctrl-Alt and provide
an alternative accelerator for activating the menu, like Ctrl_Alt-M?

Kevin