CODEWITHSUNDEEP
iosobjective-c
user2816767
user2816767

Reputation: 1

Objective c method not printing

I am new to objective c and I wanted to practice by making a simple program. For some reason the method print will not operate. Any ideas? 

#import <Foundation/Foundation.h>

@interface person: NSObject
{
    //----Variables----
    int age;
}
    //----Methods----
    -(void) print;
    -(void)setAge: (int) a;
    @end

@implementation person
-(void) print{
    NSLog(@"You are %i years old!", age);
}
-(void) setAge: (int) a{
    age=a;
}
@end

int main(int argc, char *argv[]){
        @autoreleasepool{
         person *alex; alex = [person alloc];
         [alex setAge:12];
         [alex print];
         return 0;
     }
}

Upvotes: 0

Views: 139

Answers (3)

mah
mah

Reputation: 39807

person *alex; alex = [person alloc]; is the problem -- you never initialized the object.

person *alex = [[person alloc] init]; is the common way to complete this.

person *alex = [person new]; is a good shortcut (when you're using the standard init method only).

Upvotes: 1

DarkDust
DarkDust

Reputation: 92384

  • Class names should start with an uppercase letter by convention, so it should be Person instead of person everywhere.

  • You allocated an instance of the object via [person alloc] (again, should be [Person alloc]) but you haven't initialized it. You need to call an initializer, as in [[Person alloc] init]. (In this specific case, it's not strictly necessary but please always do it nevertheless).

Apart from that, the program works. I get this in the debug console:

2013-10-19 15:20:10.757 Test[13551:303] You are 12 years old!
Program ended with exit code: 0

Upvotes: 2

Peter Segerblom
Peter Segerblom

Reputation: 2823

First off you need to initialize your object.

person *alex = [[person alloc] init];

Upvotes: 0

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