ConsumeHardwareButtonEvents.mm

/*
- Required entitlement:
<key>com.apple.springboard.hardware-button-service.event-consumption</key>
<true/>

- Required framework:
/System/Library/PrivateFrameworks/SpringBoardServices.framework/SpringBoardServices
*/

#import <UIKit/UIKit.h>
#import <objc/message.h>

@interface ViewController : UIViewController
@property (retain) id hardwareButtonService;
@property (retain, nullable) id eventConsumerInfo;
@end

@implementation ViewController

- (instancetype)initWithCoder:(NSCoder *)coder {
    if (self = [super initWithCoder:coder]) {
        _hardwareButtonService = [reinterpret_cast<id (*)(Class, SEL)>(objc_msgSend)(NSClassFromString(@"SBSHardwareButtonService"), NSSelectorFromString(@"sharedInstance")) retain];
    }
    
    return self;
}

- (void)dealloc {
    reinterpret_cast<void (*)(id, SEL)>(objc_msgSend)(_eventConsumerInfo, NSSelectorFromString(@"invalidate"));
    [_hardwareButtonService release];
    [_eventConsumerInfo release];
    [super dealloc];
}

- (void)consumeAnyPressEventForButtonKind:(long)arg1 {
    NSLog(@"Triggered! %ld", arg1);
}

- (IBAction)consume:(id)sender {
    reinterpret_cast<void (*)(id, SEL)>(objc_msgSend)(self.eventConsumerInfo, NSSelectorFromString(@"invalidate"));
  
    /*
     1 : Home Button
     2 : Sleep Button
     3 : Volume Up Button
     4 : Volume Down Button
     5~6 : Reserved?
     
     <1, >6 : NSAssert
     0x1853cb27c <+48>:  sub    x8, x22, #0x1
     0x1853cb280 <+52>:  cmp    x8, #0x6
     0x1853cb284 <+56>:  b.hs   0x1853cb2ec               ; <+160>
     */
    self.eventConsumerInfo = reinterpret_cast<id (*)(id, SEL, long, id, long)>(objc_msgSend)(self.hardwareButtonService, NSSelectorFromString(@"beginConsumingPressesForButtonKind:eventConsumer:priority:"), 1, self, 0);
}

- (IBAction)invalidate:(id)sender {
    reinterpret_cast<void (*)(id, SEL)>(objc_msgSend)(self.eventConsumerInfo, NSSelectorFromString(@"invalidate"));
    self.eventConsumerInfo = nil;
}

@end