Custom delegate not getting called - ios

Question

I am trying to use Delegates to communicate thru view controllers. Here is my code:
#protocol ViewControllerDelegate;
#interface ViewController : UIViewController <UITextFieldDelegate>{
IBOutlet UIDatePicker *dateTimePicker;
}
#property (nonatomic, strong) IBOutlet UITextField *className;
#property (nonatomic, strong) IBOutlet UITextField *assignmentTitle;
#property (nonatomic, strong) IBOutlet UITextField *assignmentDescription;
#property (nonatomic, strong) IBOutlet UISwitch *procrastinationNotificationSwitch;
#property (nonatomic, strong) IBOutlet UILabel *notificationOnOffLabel;
#property (nonatomic, assign) id <ViewControllerDelegate> delegate;
#property (nonatomic,strong)classObject *classObject;
-(IBAction) addButton:(id)sender;
#end
#protocol ViewControllerDelegate <NSObject>
-(void)assignmentSaved:(classObject *)classObj;
In action:
[self.delegate assignmentSaved:self.classObject];
In other view controller:
-(ViewController *)vc
{
if (!_vc) {
_vc = [[ViewController alloc]init];
}
return _vc;
}
- (void)viewDidLoad
{
[super viewDidLoad];
self.vc.delegate = self;
}
-(void)assignmentSaved:(classObject *)classObj
{
NSLog(#"%#",classObj.description);
classObj2 = classObj;
[self.tableView reloadData];
}
vc is a property of View Controller. When I NSLog the delegate, the delegate ends up to be nil. Also I tried #mialkan answer yet it still does not work. If you need any more info just ask.

Answer 1

I made some changes in your code, and dont forget to #synthesize delegate; and dont for get to setDelegate:self where you create ViewController.
#protocol ViewControllerDelegate;
#interface ViewController : UIViewController <UITextFieldDelegate>{
IBOutlet UIDatePicker *dateTimePicker;
id <ViewControllerDelegate> delegate;
}
#property (nonatomic, strong) IBOutlet UITextField *className;
#property (nonatomic, strong) IBOutlet UITextField *assignmentTitle;
#property (nonatomic, strong) IBOutlet UITextField *assignmentDescription;
#property (nonatomic, strong) IBOutlet UISwitch *procrastinationNotificationSwitch;
#property (nonatomic, strong) IBOutlet UILabel *notificationOnOffLabel;
#property (nonatomic, assign) id <ViewControllerDelegate> delegate;
#property (nonatomic,strong)classObject *classObject;
-(IBAction) addButton:(id)sender;
#end
#protocol ViewControllerDelegate
-(void)assignmentSaved:(classObject *)classObj;
#end

Answer 2

In the first view did you subscribe to your delegate < ViewControllerDelegate > ?
MyOtherViewController : UIViewController <ViewControllerDelegate>
and you can only do that :
- (void)viewDidLoad
{
[super viewDidLoad];
if (!_vc)
_vc = [[ViewController alloc]init];
self.vc.delegate = self;
}