创建主事件循环（用于热键等）

Question

我正在尝试编写一个独立的应用程序来注册全局热键。下面是我用gcc -framework Foundation -framework AppKit -framework Carbon -lstdc++ namsg.mm -o namsg编译的代码。

我已经加入了

    do {
        event = [NSApp nextEventMatchingMask:NSAnyEventMask untilDate:[NSDate distantFuture] inMode: NSDefaultRunLoopMode dequeue:YES];
        if (event != nil) {
            [self handleEvent:event];
        }
    } while(true);

然而我的（Command + 3）热键没有被拿起。这个热键组合确实有效，因为我能够使用javascript FFI来提取这些代码，但现在我正在尝试使用Objective-C ++。

我也试过

[[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]];

我是否应该采用另一种方式创建主事件循环？

#import <Foundation/Foundation.h>
#import <AppKit/AppKit.h>
#import <Carbon/Carbon.h>

void showAlert() {
    NSAlert *alert = [[[NSAlert alloc] init] autorelease];
    [alert setMessageText:@"Hi there."];
    [alert runModal];
}

OSStatus MyHotKeyHandler(EventHandlerCallRef nextHandler, EventRef theEvent, void *userData) {
    //Do something once the key is pressed
    showAlert();

    return noErr;
}

void registerHotkey() {
    EventHotKeyRef gMyHotKeyRef;
    EventHotKeyID gMyHotKeyID;
    EventTypeSpec eventType;
    eventType.eventClass=kEventClassKeyboard;
    eventType.eventKind=kEventHotKeyPressed;

    OSStatus installed = InstallApplicationEventHandler(&MyHotKeyHandler,1,&eventType,NULL,NULL);

    gMyHotKeyID.signature='htk1';
    gMyHotKeyID.id=1;

    OSStatus registered = RegisterEventHotKey(20, cmdKey, gMyHotKeyID, GetApplicationEventTarget(), 0, &gMyHotKeyRef);
}

int main(int argc, char * argv[]){

    registerHotkey();


    NSEvent* event;

    do {
        event = [NSApp nextEventMatchingMask:NSAnyEventMask untilDate:[NSDate distantFuture] inMode: NSDefaultRunLoopMode dequeue:YES];
        if (event != nil) {
            [self handleEvent:event];
        }
    } while(true);

    return 0;
}