What is the Cocoa equivalent of UpdateSystemActivity?

问题

I'm converting a Carbon app to a Cocoa app and I can't find the Cocoa equivalent for:

UpdateSystemActivity(UsrActivity);

Any Mac people out there care to point me in the right direction? Thanks.

UPDATE: I'm building 64bit. Building 32bit works fine, but I get symbol not declared in this scope errors for UpdateSystemActivity (and others) when I build for 64bit.

UPDATE2: I'm importing the following:

#import <Cocoa/Cocoa.h>
#import <Carbon/Carbon.h>
#import <OpenGL/CGLMacro.h>

Is there some other thing I need to import when building 64bit?

UPDATE3: Adding #import <CoreServices/CoreServices.h> did not help. I still get compiler errors telling me UpdateSystemActivity and UsrActivity was not declared in this scope.

UPDATE4: Okay, file not found on OSServices/Power.h. I'm building against the 10.5 SDK and a quick search shows:

$ pwd
/Developer/SDKs
$ find . -name Power.h
./MacOSX10.3.9.sdk/Developer/Headers/CFMCarbon/OSServices/Power.h
./MacOSX10.3.9.sdk/Developer/Headers/CFMCarbon/Power.h
./MacOSX10.3.9.sdk/Developer/Headers/FlatCarbon/Power.h
./MacOSX10.3.9.sdk/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/OSServices.framework/Versions/A/Headers/Power.h

./MacOSX10.4u.sdk/Developer/Headers/CFMCarbon/OSServices/Power.h
./MacOSX10.4u.sdk/Developer/Headers/CFMCarbon/Power.h
./MacOSX10.4u.sdk/Developer/Headers/FlatCarbon/Power.h
./MacOSX10.4u.sdk/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/OSServices.framework/Versions/A/Headers/Power.h

./MacOSX10.5.sdk/Developer/Headers/FlatCarbon/Power.h
./MacOSX10.5.sdk/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/OSServices.framework/Versions/A/Headers/Power.h

Yet I get:

Mac.mm:6:29: error: OSServices/Power.h: No such file or directory
Mac.mm:6:29: error: OSServices/Power.h: No such file or directory

回答1:

You should still be able to call UpdateSystemActivity from within your Cocoa app -- it has not been marked deprecated.

The documentation for the API specifies importing CoreServices/CoreServices.h to get the API -- however hunting through the headers (notably in OSServices/OSServices.h) shows that the file is omitted in a 64bit environment. Nevertheless, there are sections of Power.h (where UpdateSystemActivity is defined) that are turned off for 64bits, and UpdateSystemActivity is not one of them.

In light of that, try to #import <OSServices/Power.h> directly and see if that works. (You'll have to include the CoreServices framework in your project for the header to be found as well.)

回答2:

In OS X 10.6 and later IOKit can be used to disable sleep. Create an IOPMAssertion when you want to disable sleep and destroy it when you want to allow sleep again.

#import <IOKit/pwr_mgt/IOPMLib.h>

// kIOPMAssertionTypeNoDisplaySleep prevents display sleep,
// kIOPMAssertionTypeNoIdleSleep prevents idle sleep
// reasonForActivity is a descriptive string why sleep is disabled

CFStringRef* reasonForActivity= CFSTR("Describe Activity Type");

IOPMAssertionID assertionID;
IOReturn success = IOPMAssertionCreateWithName(kIOPMAssertionTypeNoDisplaySleep, kIOPMAssertionLevelOn, reasonForActivity, &assertionID);

if (success == kIOReturnSuccess)
{ 
    //Add the work you need to do without the system sleeping here.

    success = IOPMAssertionRelease(assertionID);
    //The system will be able to sleep again.
}

More information: https://developer.apple.com/library/mac/qa/qa1340/_index.html

回答3:

The issue here appears to be the line in OSServices.h that excludes Power.h if __LP64__ is defined. When building 64 bit on 10.5 UpdateSystemActivity is indeed undefined.

The good news is that the symbol does actually exist in CoreServices.framework. There are two ways to get access to it.

Forward declare it: extern "C" OSErr UpdateSystemActivity(UInt8);
Explicitly include Power.h, which you tried. The issue with your attempt is that OSServices/ doesn't find it's way into the search path. You can include it like so: #import </Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/CoreServices.framework/Frameworks/OSServices.framework/Headers/Power.h>

I don't have a copy of SnowLeopard handy, but the next thing to do would be to check if it's fixed there. If it isn't, file a RADAR as this is clearly an SDK bug.

来源：https://stackoverflow.com/questions/1324814/what-is-the-cocoa-equivalent-of-updatesystemactivity

标签

cocoa

macos

power-management