UIStatusBarSignalStrengthItemView and signalStrengthRaw to calculate the cell signal strength , does not update values in background

Question

We are using private frameworks (which includes UIStatusBarSignalStrengthItemView.h) to calculate the cell signal strength. It works perfectly in foreground mode, but as soon as my app enters background it stops updating the cell signal strength.

The code we are using is :

UIApplication *app = [UIApplication sharedApplication];
NSArray *subviews = [[[app valueForKey:@"statusBar"] valueForKey:@"foregroundView"] subviews];
            NSString *dataNetworkItemView = nil;
            for (id subview in subviews) {
                if([subview isKindOfClass:[NSClassFromString(@"UIStatusBarSignalStrengthItemView") class]]) {
                    dataNetworkItemView = subview;
                    break;
                }
            }
int signalStrength = [[dataNetworkItemView valueForKey:@"signalStrengthRaw"] intValue];

Please note that we are using the application for enterprise purpose, so we don't need to worry about Apple's rejection for using private frameworks.

Any help will be highly appreciated.

Answer 1

The [app valueForKey:@"statusBar"] will be equal to nil in background state. It's because statusBar is not accessible in your app from bg.