Register Global Hotkey under Qt and Mac OS X - c++

Question

Having read through various posts and threads that lead me nowhere I need your help.
I do have a Qt Application for Mac OS X that at some point of use will be in the background and not active. When this is the case I want to add a global hotkey so that the user can easily turn certain features on or off by clicking pre-defined hotkeys.
The following isn't working while the app is in the background and not focused.
QShortcut *shortcut = new QShortcut(QKeySequence(Qt::Key_F12), parent);
shortcut->setContext(Qt::ApplicationShortcut);
So far I found Qxt which happens to be outdated for Qt 5.5.
Then there is DDHotkey which requires a certain compiler which we can not use for various reasons.
Lastly, I found the solution of adding a global AppleScript which registers an event, again, not what I am looking for.
tell application "System Events" to tell process "myApp"
click menu item "myButton" of menu 1 of menu bar item "Menu" of menu bar 1
end tell
Is there a way to use objective-c or cocoa to accomplish exactly what I am looking for?
Please lead me in the right direction if I may have missed something.
Thanks in advance!
To those who seek a more Qt way, check the following repository:
https://github.com/ddqd/qxtglobalshortcut5
It makes use of the outdated qxt library but gets it working again.
The person tested it until Qt 5.4, we use it successfully under Qt 5.5.

Answer 1

This might be what you're looking for
https://github.com/jaz303/JFHotkeyManager
You could also look at this example from Apple, using the RegisterEventHotKey API call which I think will point you in the right direction.
https://developer.apple.com/library/prerelease/mac/samplecode/FunkyOverlayWindow/Listings/FunkyOverlayWindow_OverlayWindow_m.html#//apple_ref/doc/uid/DTS10000391-FunkyOverlayWindow_OverlayWindow_m-DontLinkElementID_8
Or you could try this code
#import <Carbon/Carbon.h>
EventHandlerUPP hotKeyFunction;
pascal OSStatus hotKeyHandler(EventHandlerCallRef nextHandler,EventRef theEvent, void *userData)
{
Notify *obj = userData;
[obj foo];
return noErr;
}
#implementation Notify
- (id)init
{
self = [super init];
if (self) {
//handler
hotKeyFunction = NewEventHandlerUPP(hotKeyHandler);
EventTypeSpec eventType;
eventType.eventClass = kEventClassKeyboard;
eventType.eventKind = kEventHotKeyReleased;
InstallApplicationEventHandler(hotKeyFunction,1,&eventType,self,NULL);
//hotkey
UInt32 keyCode = 80; //F19
EventHotKeyRef theRef = NULL;
EventHotKeyID keyID;
keyID.signature = 'FOO '; //arbitrary string
keyID.id = 1;
RegisterEventHotKey(keyCode,0,keyID,GetApplicationEventTarget(),0,&theRef);
}
return self;
}
- (void)foo
{
}
#end
And the header
#include "notify.mm"
#interface Notify
- (id)init;
- (void)foo;
#end
Simply this is just a object with a method and a constructor, in objective-c this is called init, or initialize, and variants. Calling it should be straight forward with "new".
E.x
#include "notify.h"
int main(){
Notify* object = new Notify();
}
However, some basic understanding of Objective-C is needed. It's mostly syntax differences in my opinion. But I'm no Objective-C expert myself. Anyway, there is a lot of ways to solve it, this might not be the best idea. You can also call Objective-C code from inside of a C++ class of yours. Take a look at the links bellow for a great example of how that's done.
https://el-tramo.be/blog/mixing-cocoa-and-qt/
https://github.com/remko/mixing-cocoa-and-qt/
http://philjordan.eu/article/mixing-objective-c-c++-and-objective-c++