扩展坞显示或隐藏时的事件

当 Dock 显示或隐藏时如何获取事件？

如果扩展坞可见或未使用 Carbon，您会收到通知。我不知道有什么方法可以在可可中做到这一点。

（我没有测试过这个；它来自代码here http://www.cocoabuilder.com/archive/cocoa/210267-could-keventappsystemuimodechanged-arrive-too-early-to-my-handler.html)

创建您的回调方法：

#import <Carbon/Carbon.h>

static const EventTypeSpec appEvents[] = {
    { kEventClassApplication, kEventAppSystemUIModeChanged }
};

OSStatus DockChangedHandler(EventHandlerCallRef inCallRef, EventRef event, void *userData) {
    OSStatus status = eventNotHandledErr;
    switch(GetEventClass(event)) {
        case kEventClassApplication: {
            SystemUIMode *outMode;
            SystemUIOptions *outOptions;
            GetSystemUIMode(outMode, outOptions);
            status = noErr;
        }
            break;

        default: 
            return;

    }

    /*Insert whatever you want to do when you're notified of a dock change*/

    return status;
}

然后将其放在您想要开始监听通知的任何位置：

    InstallApplicationEventHandler(NewEventHandlerUPP(DockChangedHandler), GetEventTypeCount(appEvents), appEvents, 0, NULL);

更多信息：http://developer.apple.com/library/mac/#technotes/tn2002/tn2062.html http://developer.apple.com/library/mac/#technotes/tn2002/tn2062.html