adding input parameter to method makes it stop working - ios

Question

Lets say I have a very simple method in my ViewController that returns a number.
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
NSLog(#"Number: %i",self.returnNumber);
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)returnNumber
{
NSInteger number = 2;
return number;
}
#end
This works just fine, but when I modify the method returnNumber to accept an input parameter like so:
#import "ViewController.h"
#interface ViewController (
)
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
NSLog(#"Number: %i",self.returnNumber:2);
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(NSInteger)returnNumber:(NSInteger)insertedNumber
{
NSInteger number = insertedNumber;
return number;
}
#end
The compiler says:
Property 'returnNumber' not found on object of type 'ViewController *'
Is it some kind of bug or did I totally fail to learn how Objective-C methods work?

Answer 1

Is it some kind of bug or did I totally fail to learn how Objective-C methods work?
The latter. You're confusing message send and property accessor notation. Property accessor methods can't take any arguments. What you want instead are:
I. [self returnNumber:2]
II. A good Objective-C beginner's guide, with special regards to syntax and properties. Here's Apple's official material on the subject for a starter.

Answer 2

Declare method in .h file.
-(NSInteger)returnNumber:(NSInteger)insertedNumber;
and call the method like this
[self returnNumber:2];

Answer 3

You have to put it in brackets like this
[self returnNumber:2]
That should fix the problem.

Answer 4

NSLog(#"Number: %i",[self returnNumber:2]);
try this for more about Methods and Messaging

Answer 5

[self returnNumber:2] will be the solution. As self defines its own class or viewController and to call a method of the same class we call that method using self.