Question

Ok so I have a small program that has the following files;

– HomeViewController (.h .m .xib)

– DataViewController (.h .m .xib)

– AppDelegate (.h .m)

– Person (.h .m) [OBJECT]

+ Supporting files, etc…

Say I am getting user input through text boxes and other inputs in HomeViewController and setting them as properties of an instance of Person (age, grade, etc… ), how do I access them (the same instance) from DataViewController to display them?

Here is a snippet of code from HomeViewController.h and .m
.h

@interface HomeViewController : UIViewController {

    IBOutlet UIButton *done;

    BOOL standardRes;
}

@property (nonatomic) int newAge;
@property (nonatomic) int newGrade;

-(IBAction)doneButtonPressed;

@end

.m

@implementation HomeViewController
@synthesize newAge, newGrade;

-(IBAction)doneButtonPressed{
    Person *user = [[Person alloc]init]; //Creating an instance of Person called user
    user.age = newAge; //Do I even need this if I use setters and getters in person.m?
    user.grade = newGrade; //Do I even need this if I use setters and getters in person.m?
    NSLog(@"Age: %i, Grade: %i", user.age, user.grade); //Testing with NSLog

    newAge = 175;
    [user setAge:(int)newAge]; //Calling setter method for property 'age' in Person.m

    DataViewController *vc = [[DataViewController alloc]init];
    [self.navigationController pushViewController:vc animated:YES];
}

And here is a little bit of Person.h and .m

@interface Person : NSObject {

}

@property (nonatomic, getter = age, setter = setAge:) int age;
@property (nonatomic) int grade;

@end

@implementation Person
@synthesize age, grade;

-(void)setAge: (int) newAge {
    age = newAge;
}

-(int)age {
    return age;
}

@end

NOTES:
– Using Navigation Controller
– iOS 6
– xCode 4.5.1
+ If you need any more info let me know! 🙂

P.S. I’m somewhat new to this stuff so this might be a dumb question 😉

Answer 1

Instead of

DataViewController *vc = [[DataViewController alloc]init];

Create your own initializer, and pass in a Person object. i.e.

DataViewController.h

- (id)initWithPerson:(Person*)person;

// Need a way to store it, either through a property
@property (nonatomic, strong) Person* person;

DataViewController.m

// Or you can store it as an instance variable, via Class Extension
@interface DataViewController() {
    Person* m_person;
}
@end

// Either way you store it, do it here
-(id)initWithPerson:(Person*)person {
    self = [super init];
    if (self) {
        self.person = person;
        // OR
        m_person = person;
    }
    return self;
}

HomeViewController.m

-(IBAction)doneButtonPressed {
    Person *user = [[Person alloc]init]; //Creating an instance of Person called user
    user.age = newAge; //Do I even need this if I use setters and getters in person.m?
    user.grade = newGrade; //Do I even need this if I use setters and getters in person.m?
    NSLog(@"Age: %i, Grade: %i", user.age, user.grade); //Testing with NSLog

    newAge = 175;
    [user setAge:(int)newAge]; //Calling setter method for property 'age' in Person.m

    DataViewController *vc = [[DataViewController alloc]initWithPerson:user];
    [self.navigationController pushViewController:vc animated:YES];
}