Re: [gtk-vnc-devel] PATCH: make keyboard & pointer grabs configurable

[Anthony Liguori <anthony codemonkey ws>]

Daniel P. Berrange wrote:
> On Mon, Jul 09, 2007 at 11:00:02AM +0200, Gerd Hoffmann wrote:
>   
> > > So this patch adds two options.
> > >
> > >   - A pointer grab flag - if this is set, then the pointer will always be
> > >     grabbed upon first click, regardless of mouse mode
> > >
> > >   - A keyboard grabb flag - if this is set, then the keyboard will always
> > >     be grabbed upon mouse enter, an ungrabed on mouse leave.
> > >       
> > I wouldn't separate these two for usability reasons.  Input (both kbd
> > and mouse) should either be grabbed or not grabbed (and the grab state
> > should be clear to the user, but that isn't the job of the widget but
> > the using apps I guess).
> >     
>
> There is no reason to grab the mouse if the guest OS is operating in 
> absolute pointer mode - eg if using a USB tablet, or if you have configured
> the X server to use Xen's paravirt mouse with evdev.
>
> You may still want to grab the keyboard whenever the mouse is over the
> widget though, so that window manager short cuts get seen by the guest
> instead of the host. I don't want to have my mouse constrained to the
> window just so that keyboard shortcuts work.
>
>   
> > You probably want to allow different events trigger the input grab though.
> >     
>
> Well keyboard grab is doe
>
>   
> > > this to add 'Press Ctrl+Alt to release pointer' to the title bar.
> > >       
> > One of the obvious reasons for that is that there is one "release grab"
> > hotkey only.
> >     
>
> Two primary scenarios I have
>
>   - Grab both  keyboard & mouse at same time - upon first click - in this
>     case there's  only a single ungrab hotkey needed
>   - Grab keyboard only when mouse is over the VNC widget - there's no
>     ungrab hotkey needed at all - simply move the mouse outside the
>     widget
>   

So this should be an option within gtk-vnc instead of being something 
implemented externally to it.  I agree that you really don't want 
keyboard grab exposed as a separate option except for this one very 
special case.

Regards,

Anthony Liguori

> The first is applicable when the server / guest OS can only work with
> relative mouse co-ords & thus needs a mouse grab. The second is applicable
> when the server/guest works in absolute mouse mode & thus does not need 
> any mouse grab
>
> Dan.
>