Why does my array stay empty?

Question

Hi i'm a objC noob. I have a problem filling an NSMutableArray with objects.

for(id p in tmpArray){
    Person *person = [[Person alloc] init];
    person.usrName = p;
    [persons addObject:person]; // after this line the persons
                                // array is still empty
    [person release];
}

Persons is a property NSMutableArray and the problem is that it's empty. Is it the release of the person object too early or have I instanciated it wrong?

Answer 1

Make sure you've alloced and initialised the array before you try to add things to it

Answer 2

You need to initialize your array in the -init method, like this:

NSMutableArray *array = [[NSMutableArray alloc] init];
self.persons = array; // will be automatically retained 
                      // because you're using the property
[array release]; // we alloced - we release it

Don't forget to release it:

-(void)dealloc {
     self.persons = nil; // previous value of property 'persons' will be released
     [super dealloc];
}