目标 c - 将 CGEvents 击键发送到后台应用程序

Question

我正在尝试将回车键发送到后台应用程序，如下所示：

CGEventRef a = CGEventCreateKeyboardEvent(eventSource, 36, true);
CGEventRef b = CGEventCreateKeyboardEvent(eventSource, 36, false);
CGEventPostToPSN(&psn, a);
CGEventPostToPSN(&psn, b);

它不起作用，我认为这是因为该应用程序必须是接收击键的最前端应用程序？我说的对吗？如果是这样，我是否可以在不先激活应用程序的情况下发送此事件？如果不是，那我做错了什么？谢谢。

Answer 1

后台应用不会对关键事件执行操作。有两个选项可以让应用在后台处理它们："事件点击"和"+[NSEvent addLocalMonitorForEventsMatchingMask:]"。NSEvent选项非常简单：

// A block callback to handle the events
NSEvent * (^monitorHandler)(NSEvent *);
monitorHandler = ^NSEvent * (NSEvent * theEvent){
    NSLog(@"Got a keyDown: %d", [theEvent keyCode]);
    // The block can return the same event, a different 
    // event, or nil, depending on how you want it to be 
    // handled later. In this case, being in the background, 
    // there won't be any handling regardless.
    return theEvent;
};
// Creates an object that we don't own but must keep track of to
// remove later (see docs). Here, it is placed in an ivar.
monitor = [NSEvent addLocalMonitorForEventsMatchingMask:NSKeyDownMask 
                                                handler:monitorHandler];

但是你已经在玩事件水龙头了，所以你可能只想走这条路。

// Creates an object that must be CFRelease'd when we're done
CFMachPortRef tap = CGEventTapCreateForPSN(myOwnPSN, 
                                       kCGTailAppendEventTap,
                                       kCGEventTapOptionDefault, 
                                       kCGEventKeyDown,
                                       myEventTapCallback, 
                                       NULL);

回调很简单。有关信息，请参阅事件服务参考中的回调。