Protocol simple example

ViewController.h

#import <UIKit/UIKit.h>

#import "MyVC.h"

@interface ip20ViewController : UIViewController <MyVCDelegate>

{

    MyVC *myvc;

}

@end

ViewController.m

- (void)clickPressed:(NSString *)message

{

    NSLog(@"%@", message);

    [myvc dismissViewControllerAnimated:YES completion:nil];

}

- (void)viewDidAppear:(BOOL)animated

{

    [super viewDidAppear:animated];

    myvc = [[MyVC alloc] init];

    myvc.delegate = self;

    [self presentViewController:myvc animated:YES completion:nil];

}

MyVC.h

 

#import <UIKit/UIKit.h>

@protocol MyVCDelegate <NSObject>

@optional

- (void)clickPressed:(NSString *)message;

@end

@interface MyVC : UIViewController

@property (nonatomic, strong) id<MyVCDelegate> delegate;

- (IBAction)click:(id)sender;

@end

MyVC.m

@synthesize delegate;

- (IBAction)click:(id)sender

{

    [delegate clickPressed:@"Just Clicked!"];

}