BackBoardServices.framework

From iPhone Development Wiki
Jump to: navigation, search
BackBoardServices.framework
Private Framework
Availabile 6.0 – present


BackBoardServices is a framework that was introduced in iOS 6.0. It serves as a communication bridge between SpringBoard and backboardd. The framework itself has no function other than to communicate between SpringBoard's Mach messaging server and backboardd's XPC server. It is solely a small wrapper around the XPC API, to keep SpringBoard and backboardd from having to deal with it directly.

The innards of BackBoardServices are quite simple. Almost every function in BackBoardServices creates an XPC connection with the opposing process, and then sends an XPC object identifying the function called. Then, the destination (being either SpringBoard or backboardd) receives the object, and performs the actual function, sending back a return value if necessary.

BackBoardServices can be used for many system and hardware functions, including launching/closing applications, setting the backlight level and more.

Killing an application

extern "C" void BKSTerminateApplicationForReasonAndReportWithDescription(NSString *bundleID, int reasonID, bool report, NSString *description);
...
BKSTerminateApplicationForReasonAndReportWithDescription(@"com.apple.mobilesafari", 5, false, NULL);

You can specify the reason of terminating application (last argument) and choose whether to report this crash to system crash reporter (3rd argument).

BKSTerminateApplicationForReasonAndReportWithDescription(@"com.apple.mobilesafari", 5, true, @"Killed because X.");

Killing all applications

Again, it is not mandatory to specify a description but it is a good thing to consider doing.

extern "C" void BKSTerminateApplicationGroupForReasonAndReportWithDescription(int applicationGroupID, int reasonID, bool report, NSString *description);
...
BKSTerminateApplicationGroupForReasonAndReportWithDescription(1, 5, 21, @"Kill ALL the apps!");

Setting Backlight Level

The factor should be a number from 0.0 to 1.0, inclusive.

extern "C" void BKSHIDServicesSetBacklightFactorWithFadeDuration(float factor, int duration);
...
BKSHIDServicesSetBacklightFactorWithFadeDuration(0.5, 0);

Detecting Ambient Light Sensor

Check if Ambient Light Sensor exists or not. return 1 if exists.

extern "C" int BKSHIDServicesAmbientLightSensorExists();
...
NSLog(@"Ambient Light Sensor exists: %i", BKSHIDServicesAmbientLightSensorExists());