Re: [Qemu-devel] [PATCH v5] cocoa.m: Add ability for user to specify mouse ungrab key

[BALATON Zoltan]

On Wed, 31 Jan 2018, Programmingkid wrote:
> > > Basically there is a array that acts as a check list. It checks off
> > > keys that belong to the ungrab sequence as they are detected. Once a
> > > non-ungrab key is detected, the check list is cleared. If all the
> > > ungrab keys are detected the ungrab code is executed. This only
> > > happens on keyup events. That way if Control-ALT were the ungrab keys,
> > > sending Control-ALT-Delete to the guest is still possible because
> > > these are the keys detected on the keyup event. The Delete key would
> > > have cleared the check list. Daniel Berrange is the one I can thank
> > > for this idea. He might be able to explain it better than me.
> >
> > Hmm, ok.
> >
> > Doing the same for gtk would basically imply to not use any toolkit
> > support for hotkeys ...
> >
> > It'll also become more difficuilt if we use that for multiple hotkeys.
> >
> > But possibly we can share the code across all UIs, now that keycodemapdb
> > is used by qemu.  So first translate the keycode from the UI toolkit to
> > a QKeyCode, then feed that into shared hotkey detection code.
>
> Sounds like a good idea. I will be more than happy to help. My cocoa code
> uses sets to implement keeping track of key presses. A set is a collection of 
> data
> that only allows for unique values. So no two items in a set can be the same
> value. My patch uses cocoa's NSSet so the shared code would probably not be
> able to use it. I don't currently know of an implementation of a set that is
> in C and available for us to use, so we may have to implement it ourselves.

I think we already depend on glib so maybe you could find something useful 
for this here:

https://developer.gnome.org/glib/stable/glib-data-types.html

Regards,
BALATON Zoltan