AVSystemController to disable iOS System sounds gives not found for architecture i386 error

Question

I want to silent the ringer volume. So I am using this link to do that - How to disable iOS System Sounds But if I use the code:

- (void) setSystemVolumeLevelTo:(float)newVolumeLevel
{
    Class avSystemControllerClass = NSClassFromString(@"AVSystemController");
    id avSystemControllerInstance = [avSystemControllerClass performSelector:@selector(sharedAVSystemController)];

NSString *soundCategory = @"Ringtone";

NSInvocation *volumeInvocation = [NSInvocation invocationWithMethodSignature:
                                  [avSystemControllerClass instanceMethodSignatureForSelector:
                                   @selector(setVolumeTo:forCategory:)]];
[volumeInvocation setTarget:avSystemControllerInstance];
[volumeInvocation setSelector:@selector(setVolumeTo:forCategory:)];
[volumeInvocation setArgument:&newVolumeLevel atIndex:2];
[volumeInvocation setArgument:&soundCategory atIndex:3];
[volumeInvocation invoke];

}

It crashes on

NSInvocation *volumeInvocation = [NSInvocation invocationWithMethodSignature:
                                  [avSystemControllerClass instanceMethodSignatureForSelector:
                                   @selector(setVolumeTo:forCategory:)]];

because the value returned is nil.

and If I import the framework etc and then use this code

[[AVSystemController sharedAVSystemController] setVolumeTo:0.0 forCategory:@"Ringtone"];

It does not run giving me the following error:

Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_AVSystemController", referenced from:
  objc-class-ref in SettingsViewController.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Someone please guide me where I am going wrong.

Answer 1

All you have to do is to add following lines in you first method. As you are using a private framework(Celestial) so you have to import it on runtime.

NSBundle *bundle = [NSBundle bundleWithPath:@"/System/Library/PrivateFrameworks/Celestial.framework"];
BOOL success = [bundle load];