Question

I’m getting a name and a phone number from text fields, till here all is ok.
When I’m trying to add these data to my NSMutableDictionary nothing happens.

---

ViewController.h

@property(strong,nonatomic) NSMutableDictionary *contacts;

---

ViewController.m

- (IBAction)btnAdd:(id)sender {
    self.userName = self.name.text;
    self.userPhoneNumber = self.phoneNumber.text;
    [self addToDictionary:self.userName :self.userPhoneNumber];
    NSLog(@"ADDED: Key = %@, Value = %@", self.userName, self.userPhoneNumber);
    [self clearTextFields];
}

- (void)addToDictionary: (NSString*) _name: (NSString*) _phone{
    [self.contacts setObject:_name forKey:_phone];
}

---

Error message

local declaretion of ‘_name’ hides instance variable

Answer 1

You most likely are not initializing your dictionary.

Add this to your viewDidLoad method:

self.contacts = [NSMutableDictionary new];

As far as the warning at the end, when you have a declared property, an iVar will automatically be created for you with the same name, but an _ added before. I.E. if you have name as a declared property, then an instance variable called _name is created for you. When you created your addToDictionary: method, you used the same name. This prevents you from accessing the iVar so it warns you about it. To get rid of the warning, replace _name and _phone with something else (like newName and newPhone).