Re: [Qemu-devel] [PATCH v6] ui/cocoa.m: Add ability for user to specify mouse ungrab key

[Programmingkid]

> On Feb 16, 2018, at 8:15 AM, Gerd Hoffmann <address@hidden> wrote:
> 
> On Sat, Feb 03, 2018 at 12:17:43PM -0500, John Arbuckle wrote:
>> Currently the ungrab keys for the Cocoa and GTK interface are Control-Alt-g.
>> This combination may not be very fun for the user to have to enter, so we
>> now enable the user to specify their own key(s) as the ungrab key(s). The
>> list of keys that can be used is found in the file qapi/ui.json under 
>> QKeyCode.
>> The max number of keys that can be used is three.
>> 
>> Syntax: -display cocoa,hotkey-grab=<key-key-key>
>> 
>> Example usage:  -display cocoa,hotkey-grab=home
>>              -display cocoa,hotkey-grab=shift-ctrl
>>              -display cocoa,hotkey-grab=ctrl-x
>>              -display cocoa,hotkey-grab=pgup-pgdn
>>              -display cocoa,hotkey-grab=kp_5-kp_6
>>              -display cocoa,hotkey-grab=kp_4-kp_5-kp_6
>>              -display cocoa,hotkey-grab=ctrl-alt
> 
> Finally found the time for a closer look and some testing.
> 
> Problem is the hotkeys are all forwarded to the guest.
> So when using -- for example -- the pgup-pgdn hotkey
> and you press the combination the guest will see it.
> 
> I see basically two options to deal with that:
> 
> (a) Make the code more clever.  On pgup keydown event
>    the code has to figure this might be part of a hotkey
>    sequence, hold back the event to see what comes next.
>    - If the next event is pgup keyup -> ok, normal pgup
>      keypress, forward both keydown and keyup to the guest.
>    - If the next event is pgdn keydown -> hotkey found.
>      So do hotkey action, don't forward keydown (and
>      following keyup) events to the guest.

Ok. I think this should be doable.

> 
> (b) Restrict allowed hotkeys to modifier key(s) plus one
>    non-modifier key.  Forwarding modifier keydown+keyup
>    to the guest has typically effects inside the guest,
>    so we only have to hold back that single non-modifier
>    key.  That is alot easier to implement.

Sorry but I was using this patch to make my ungrab key F15.
This key is not used by anything and makes things so simple
for me. Requiring a modifier key in the sequence seems unnecessary. 

Thank you.