Question

Given two UIViewControllers A and B. A sits on top of a UINavigationController. B has init function initWithArray. B was made and initWithArray in A. Then B was pushed into the NavigationController to sit on top of A.

In A, this is the array that was passed in

NSArray *arrayInA; //(assuming all init and everything was done)

Making B

B *b = [[B alloc]initWithArray: arrayInA];
[self.navigationController pushViewController: B animation: YES];

In B, initWithArray goes something like this

if (self){
    arrayInB = arrayFromA;
}

arrayInB is just private property in B

NSArray *arrayInB;

The question is, which of these are different objects? arrayInA / arrayFromA / arrayInB

Edit: I am working with ARC.

Answer 1

In your code arrayInB points to the same memory address as arrayFromA which points to arrayInA. I would suggest changing your code so that arrayInB keeps a reference to the array it receives.

if (self){
   arrayInB = [arrayFromA retain];
}

or

@property (nonatomic,retain) NSArray * arrayInB;

if (self){
   self.arrayInB = arrayFromA;
}

If you want arrayInB to be its own array that points to the same objects as arrayFromA then you should do this.

if(self){
   self.arrayInB = [NSArray arrayWithArray:arrayFromA];
}