#import <UIKit/UIKit.h>

@protocol LoginViewControllerDelegate;

@interface LoginViewController : UIViewController

// We choose a name here that expresses what object is doing the delegating
@property (nonatomic, weak) id<LoginViewControllerDelegate> delegate;

@end

@protocol LoginViewControllerDelegate <NSObject>

// The methods declared here are all optional
@optional

// We name the methods here in a way that explains what the purpose of each message is
// Each takes a LoginViewController as the first argument, allowing one object to serve
// as the delegate of many LoginViewControllers
- (void)loginViewControllerDidLoginSuccessfully:(LoginViewController *)lvc;
- (void)loginViewController:(LoginViewController *)lvc didFailWithError:(NSError *)error;
- (void)loginViewControllerDidReceivePasswordResetRequest:(LoginViewController *)lvc;
- (void)loginViewControllerDiDReceiveSignupRequest:(LoginViewController *)lvc;
- (BOOL)loginViewControllerShouldAllowAnonymousLogin:(LoginViewController *)lvc;

@end

#import"LoginViewController.h"

@interface LoginViewController ()

@property (weak, nonatomic) IBOutlet UIButton *anonSigninButton;

@end

@implementation LoginViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    //  Here we ask the delegate for information used to layout the view
    BOOL anonymousLoginAllowed = NO;
    //  All our protocol methods are @optional, so we must check they are actually implemented before calling.
    if ([self.delegate respondsToSelector:@selector(loginViewControllerShouldAllowAnonymousLogin:)]) {
        // self is passed as the LoginViewController argument to the delegate methods
        // in this way our delegate can serve as the delegate of multiple login view controllers, if needed
        anonymousLoginAllowed = [self.delegate loginViewControllerShouldAllowAnonymousLogin:self];
    }
    self.anonSigninButton.hidden = !anonymousLoginAllowed;
}

- (IBAction)loginButtonAction:(UIButton *)sender
{
    // We're preteneding our password is always bad. So we assume login succeeds when allowed anonmously
    BOOL loginSuccess = [self isAnonymousLoginEnabled];
    NSError *loginError = [self isAnonymousLoginEnabled] ? nil : [NSError errorWithDomain:@"domain" code:0 userInfo:nil];

    //  Fake concurrency
    double delayInSeconds = 1.0;
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
        //  Notify delegate of failure or success
        if (loginSuccess) {
            if ([self.delegate respondsToSelector:@selector(loginViewControllerDidLoginSuccessfully:)]) {
                [self.delegate loginViewControllerDidLoginSuccessfully:self];
            }
        }
        else {
            if ([self.delegate respondsToSelector:@selector(loginViewController:didFailWithError:)]) {
                [self.delegate loginViewController:self didFailWithError:loginError];
            }
        }
    });
}

- (IBAction)forgotPasswordButtonAction:(id)sender
{
    //  Notify delegate to handle forgotten password request.
    if ([self.delegate respondsToSelector:@selector(loginViewControllerDidReceivePasswordResetRequest:)]) {
        [self.delegate loginViewControllerDidReceivePasswordResetRequest:self];
    }
}

- (IBAction)signupButtonAction:(id)sender
{
    //  Notify delegate to handle signup request.
    if ([self.delegate respondsToSelector:@selector(loginViewControllerDiDReceiveSignupRequest:)]) {
        [self.delegate loginViewControllerDiDReceiveSignupRequest:self];
    }
}

- (BOOL)isAnonymousLoginEnabled
{
    BOOL anonymousLoginAllowed = NO;

    if ([self.delegate respondsToSelector:@selector(loginViewControllerShouldAllowAnonymousLogin:)]) {
        anonymousLoginAllowed = [self.delegate loginViewControllerShouldAllowAnonymousLogin:self];
    }
    return  anonymousLoginAllowed;
}

@end

#import"MainViewController.h"
#import"LoginViewController.h"

#define LOGGED_IN NO

@interface MainViewController () <LoginViewControllerDelegate>

@end

@implementation MainViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

    //  Fake loading time to show the modal cleanly
    if (!LOGGED_IN) {
        double delayInSeconds = 1.0;
        dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
        dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
            //  Create a login view controller, assign its delegate, and present it
            LoginViewController *lvc = [[LoginViewController alloc] init];
            lvc.delegate = self;
            [self presentViewController:lvc animated:YES completion:^{
                NSLog(@"modal completion finished.");
            }];
        });
    }
}

#pragma mark - LoginViewControllerDelegate


- (void)loginViewControllerDidLoginSuccessfully:(LoginViewController *)lvc
{
    NSLog(@"Login VC delegate - Login success!");
    [self dismissViewControllerAnimated:YES completion:NULL];
}

- (void)loginViewController:(LoginViewController *)lvc didFailWithError:(NSError *)error
{
    // Maybe show an alert...
    // UIAlertView *alert = ...
}

- (void)loginViewControllerDidReceivePasswordResetRequest:(LoginViewController *)lvc
{
    // Take the user to safari to reset password maybe
     NSLog(@"Login VC delegate - password reset!");
}

- (void)loginViewControllerDiDReceiveSignupRequest:(LoginViewController *)lvc
{
    // Take the user to safari to open signup form maybe
    NSLog(@"Login VC delegate - signup requested!");
}

- (BOOL)loginViewControllerShouldAllowAnonymousLogin:(LoginViewController *)lvc
{
    return YES;
}

@end

#DetailViewController.h

#import <UIKit/UIKit.h>

@protocol MasterDelegate <NSObject>
-(void) getButtonTitile:(NSString *)btnTitle;
@end


@interface DetailViewController : MasterViewController

@property (nonatomic, assign) id<MasterDelegate> customDelegate;

#DetailViewController.m

if([self.customDelegate respondsToSelector:@selector(getButtonTitile:)])
{
          [self.customDelegate getButtonTitile:button.currentTitle];    
}

#MasterViewController.m

create obj of DetailViewController

DetailViewController *obj = [[DetailViewController alloc] init];
obj.customDelegate = self;
[self.navigationController pushViewController:reportTypeVC animated:YES];

and add delegate method in MasterViewController.m for get button title.

#pragma mark -
#pragma mark - Custom Delegate  Method

-(void) getButtonTitile:(NSString *)btnTitle;
{
    NSLog(@"%@", btnTitle);

}