Question

I’m getting an error in XCode:

multiple methods named ‘setEnabled’ found with mismatched result, parameter type, or attributes

I’m using the following code within AppDelegate.m:

#import "BluetoothManager.h"
Class BluetoothManager = objc_getClass( "BluetoothManager" ) ;
id btCont = [BluetoothManager sharedInstance] ;
[btCont setEnabled:!currentState] ;

Answer 1

if you’re importing BluetoothManager.h then you have it resolved at compile-time, adjust the code to say:

#import "BluetoothManager.h"
Class BluetoothManagerClass = objc_getClass( "BluetoothManager" );
BluetoothManager *btCont = [BluetoothManagerClass sharedInstance];
[btCont setEnabled:!currentState];

are you trying to support a new class, but also run in older iOS?

in response to Q1: the “simple” version, if you’re not trying to do anything tricky, is to forego the objc_getClass which provides dynamic flexibility that is not often needed

#import "BluetoothManager.h"
BluetoothManager *btCont = [BluetoothManager sharedInstance];
[btCont setEnabled:!currentState];

This assumes:

• The class BluetoothManager is declared in “BluetoothManager.h”
• there is a class method declared (and defined) on it +sharedInstance (which to follow common Objective-C naming conventions, I would rename to +sharedBluetoothManager)
• BluetoothManager declares a method called -setEnabled: