How to dismiss own view controller and present another view controller in a button tap?

Question

Let's say I have 3 view controller labeled "A","B" and "C". Right now, "A" is the rootViewController of the window and it presents "B" modally when a button is tapped. In "B", when a button is tapped it is supposed to be dismissed by "A" and then "A" will present C modally immediately.How can one do that? Here's my code in hope of achieving this goal but I was unsuccessful in doing so.

At "A" viewController, I declared a property to hold a block at the header file to be called when "B" viewController is dismissed by "A".

@property (nonatomic, copy) void (^presentZapLaunch)(void);

This is "A" viewController present method to present "B"

-(void)presentNextViewCon
{
CYCGestureZapZapViewController *gestureViewCon = [[CYCGestureZapZapViewController alloc]init];

if (!self.presentZapLaunch) {
    __weak CYCZapZapViewController *weakRefCon = self;

    self.presentZapLaunch = ^{
        CYCZapZapViewController *preventWeakRefCon = weakRefCon;

        CYCZapZapLaunchViewController *zapLaunch = [[CYCZapZapLaunchViewController     alloc]init];
        NSLog(@"Called");
        [preventWeakRefCon presentViewController:zapLaunch animated:YES completion:nil];

    };
}


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

}

This is "B" dismiss method to dismissed by "A" and "A" should present "C" immediately

-(void)presentNextViewCon
{
NSLog(@"Hello");
[self.presentingViewController dismissViewControllerAnimated:self completion:^{[(CYCZapZapViewController *)self.presentingViewController presentZapLaunch];}];

}

*Note that I'm using "A" view controller as the rootViewController of window, and "A" presents "B" view controller modally. All "A","B" and "C" are view controllers.

Answer 1

you can do using protocol let say for example as bellow:-

In to your B viewController setting Protocol :

@class Bviewcontroller;

@protocol BviewControllerDelegate <NSObject>
- (void)BviewcontrollerDidTapButton:
(Bviewcontroller *)controller;

@end

@interface Bviewcontroller : UIViewcontroller

@property (nonatomic, weak) id <BviewControllerDelegate> delegate;
- (IBAction)ButtonTap:(id)sender;

@end

in .m class

- (IBAction)ButtonTap:(id)sender
{
    [self.delegate BviewcontrollerDidTapButton:self];
}

Now in to you A_viewController .h class:

#import "Bviewcontroller.h"

@interface A_viewController : UIViewcontroller<BviewControllerDelegate>

.m class

- (void)BviewcontrollerDidTapButton:
(Bviewcontroller *)controller
{
    [self dismissViewControllerAnimated:YES completion:^{


      // here you can create a code for presetn C viewcontroller 

    }];
}

IMPORTANT when you preseting Bviewcontroller from A_viewController do not set delegate with object like

-(void)presentNextViewCon
{
                bViewcontroller *gestureViewCon = [[bViewcontroller alloc]init];
        gestureViewCon.delegate = self;

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

}

UPDATE

Here it is i create a demo that working like:

SAMPLE CODE LINK http://speedy.sh/2acSC/modelDemo.zip