How to call delegate when VC is dismissed? - ios

Question

I have two VC. I need to call the delegate function when the 2nd VC is dismissed.
In my 1st VC or main VC I have given the following code in .h file.
#interface FirstVC : ....<SecondVCDelegate>
-(void)didDismissViewController:(UIViewController*)vc;
But for some reason SecondVCDelegate in this is not detected.
while presenting 2nd VC from first I have given this .m file of 1st VC.
SecondVC *optionsVC = [self.storyboard instantiateViewControllerWithIdentifier:#"SecondVC"];
optionsVC.delegate = self;
optionsVC.view.backgroundColor = [UIColor blackColor];
optionsVC.modalPresentationStyle = UIModalPresentationOverFullScreen;
[self presentViewController:optionsVC animated:YES completion:^{}];
in 2nd VC .h file
#protocol SecondVCDelegate <NSObject>
- (void)didDismissViewController:(UIViewController*)vc;
#end
#interface SecondVC : ...
#property (nonatomic) id<SecondVCDelegate> delegate;
#end
in 2nd VC .m file I have dismissed using the below code
[self dismissViewControllerAnimated:YES completion:nil];
Could you point out what I did wrong with possible explanation. Thanks in advance.

Answer 1

This is the working code on xcode 9 :
ViewController.m :
#import "ViewController.h"
#import "SecondViewController.h"
#interface ViewController () <SecondVCDelegate>
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)action:(id)sender {
SecondViewController *optionsVC = [self.storyboard instantiateViewControllerWithIdentifier:#"SecondViewController"];
optionsVC.delegate = self;
optionsVC.view.backgroundColor = [UIColor blackColor];
optionsVC.modalPresentationStyle = UIModalPresentationOverFullScreen;
[self presentViewController:optionsVC animated:YES completion:nil];
}
-(void) didDismissViewController:(UIViewController *)vc{
NSLog(#"working controller : %#", vc);
}
#end
SecondViewController.h :
#import <UIKit/UIKit.h>
#protocol SecondVCDelegate <NSObject>
- (void)didDismissViewController:(UIViewController*)vc;
#end
#interface SecondViewController : UIViewController
#property (weak, nonatomic) id<SecondVCDelegate> delegate;
#end
SecondViewController.m :
#import "SecondViewController.h"
#interface SecondViewController ()
#end
#implementation SecondViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)didmissAction:(id)sender {
[self dismissViewControllerAnimated:true completion:^{
[_delegate didDismissViewController:self];
}];
}
#end

Answer 2

On your 2nd VC .m do like this
First synthesize delegate below implementation
#synthesize delegate;
after that use it on viewController dismiss:
[self dismissViewControllerAnimated:YES completion:^{
[self.delegate didDismissViewController: self];
}];