accessing property in another class

ios

Solution

1. Here, your are simply creating a new instance of A, instead of accessing the existing instance of A to fetch the array inside B instance. So that only it is showing null value.

2. See this code for 2nd question....

ClassA.h

@interface ClassA:UIViewController

@property (nonatomic, retain) NSMutableArray *arrayOfPaths;

@end

ClassA.m

@implementation ClassA

@synthesize arrayOfPaths = _arrayOfPaths;

    -(id)init
    {
       self = [super init];
       if(self)
       {
        self.arrayOfPaths = [[NSMutableArray alloc] initWithObjects:@"1",@"2", nil];

        //Delegation process
        ClassB *bInstance = [[ClassB alloc] init];
        [bInstance setAReference:self];

        //Do your stuff of presenting ClassB instance here.....
       }
}
@end

ClassB.h

#import "ClassA.h"
@interface ClassB:UITableViewController

@property (nonatomic, copy) ClassA *aReference;

@end

ClassB.m

@implementation ClassB

@synthesize aReference = _aReference;
-(void)viewDidLoad
{
    NSLog(@"Array from class ClassA %@", self.aReference.arrayOfPaths);
}
@end

ClassB ViewController should be instantiated by ClassA only here.

3. You need to use the delegates concept to acheive your requirement. See the above example code

4. objective -c won't support multiple inheritance.

Problem

I have 2 classes, say for A and B. I have a mutable array _arrayOfPaths in A class now I am trying to access that array in class b. Like below: ``` A *testModel = [[A alloc]init]; NSMutableArray *array = [testModel.arrayOfPaths mutableCopy]; ``` Now when I `NSLog` this newly made array then it shows null. if I print `testModel.arrayOfPaths` then it shows null too. My questions are: - Why its showing null? - How can I access `_arrayOfPaths` in B class? - Do I need to use inheritance for it? B is already inheriting `UITableViewController`. - Is Multiple inheritance supported by objective c?

Original source