c - mac屏保启动事件

Question

屏幕保护程序启动时是否触发了事件？就像钥匙串锁定一样：

OSStatus keychain_locked(SecKeychainEvent keychainEvent, SecKeychainCallbackInfo *info, void *context){...}

Answer 1

终于找到了——解决方案是使用 NSDistributedNotificationCenter 并观察以下事件

• com.apple.screensaver.didstart
• com.apple.screensaver.willstop
• com.apple.screensaver.didstop
• com.apple.screenIsLocked
• com.apple.screenIsUnlocked

像

[[NSDistributedNotificationCenter defaultCenter]
   addObserver:self
   selector:@selector(screensaverStarted:)
   name:@"com.apple.screensaver.didstart"
   object:nil];

Answer 2

虽然没有为此的 Carbon 事件，但您可以在当前应用程序更改时收到通知，然后检查新应用程序是否为屏幕保护程序进程。

---

// Register the event handler for when applications change
{
    EventTypeSpec es;
    es.eventClass = kEventClassApplication;
    es.eventKind = kEventAppFrontSwitched;
    InstallApplicationEventHandler(&appChanged, 1, &es, NULL, NULL);
}

OSStatus appChanged(EventHandlerCallRef nextHandler, EventRef anEvent, void* userData)
{
    ProcessSerialNumber psn;    
    GetEventParameter(anEvent, kEventParamProcessID, typeProcessSerialNumber,
                      NULL, sizeof(psn), NULL, &psn);

    // Determine process name
    char procName[255];
    {
        ProcessInfoRec pInfo;
        Str255 procName255;
        FSRef ref;

        pInfo.processInfoLength = sizeof(ProcessInfoRec);
        pInfo.processName = procName255;
        pInfo.processAppRef = &ref;
        GetProcessInformation(&psn, &pInfo);

        const unsigned int size = (unsigned int)procName255[0];
        memcpy(procName, procName255 + 1, size);
        procName[size] = '\0';
    }

    if(strcmp(procName, "ScreenSaverEngine") == 0)
    {
        NSLog(@"Found %s\n", procName);
    }

    return noErr;
}

Answer 3

这不完全是问题的答案，但我花了很多时间徒劳地寻找 macOS 发布的通知列表，所以我想发布一些我为通知发现编写的代码。

该代码只需注册即可收听所有通知，并在收到通知时为每个通知打印一些信息。

import Foundation

let distCenter = CFNotificationCenterGetDistributedCenter()
if distCenter == nil {
    exit(1)
}

CFNotificationCenterAddObserver(distCenter, nil, { (center, observer, name, object, userInfo) -> Void in
        print("Event occurred: \(name)  User info: \(userInfo)")
    }, nil, nil, .DeliverImmediately)

CFRunLoopRun()