How To Call Viewcontroller A Method on dismiss Viewcontroler B Class Using Objective C?

Question

I want to pass data on Dismiss View controllerB To View controllerA and pass two text field value to View controllerABelow posted code not working for me!

ViewController B

ClassB.h

#import <UIKit/UIKit.h>

@protocol SecondDelegate <NSObject>
-(void) secondViewControllerDismissed:(NSString *)stringForFirst
@end


@interface SecondViewController : UIViewController
{
    id                              myDelegate; 
}

@property (nonatomic, assign) id<SecondDelegate>    myDelegate;

ClassB.m

@synthesize myDelegate;

//Below Code Into my button Click

if([self.myDelegate respondsToSelector:@selector(secondViewControllerDismissed:)])
{
    [self.myDelegate secondViewControllerDismissed:@"THIS IS THE STRING TO SEND!!!"];
}
[self dismissModalViewControllerAnimated:YES];

ViewController A

ClassA.h

#import "SecondViewController.h"

@interface FirstViewController:UIViewController <SecondDelegate>

ClassA.m

Now when you instantiate secondViewController in firstViewController you should do the following:

// Here I am using below Code
    ClassB *BViewController;
    [self.storyboard instantiateViewControllerWithIdentifier:@"BViewController"];
    [self presentViewController:BViewController animated:YES completion:nil];



- (void)secondViewControllerDismissed:(NSString *)stringForFirst
{
    NSString *thisIsTheDesiredString = stringForFirst; //And there you have it

}

I think you need to learn [Delegates and Protocols](https://developer.apple.com/library/ios/documentation/General/Conceptual/CocoaEncyclopedia/DelegatesandDataSources/DelegatesandDataSources.html). — Parth Bhatt, Jan 04 '16 at 06:53
Ho Okey NSObject to calling method I can do but Viewcontroller to call another calss mrthod I dont know that! — Sanju, Jan 04 '16 at 06:55
Do you mean to say want to call "Class method" of ViewController A? — Parth Bhatt, Jan 04 '16 at 06:57
Class B Viewcontroller button click to call Class A viewcontroller method with need to pass two text values or string values. — Sanju, Jan 04 '16 at 07:02
Pass Class A object as property to class B then call Class A methods. — Avijit Nagare, Jan 04 '16 at 07:04
Please read some tutorial beforehand. There are plenty you can Google. — Ayan Sengupta, Jan 04 '16 at 07:06
Refer the link [here](http://stackoverflow.com/questions/9629417/calling-a-method-from-another-class-in-objective-c) @sanju — Ronak Chaniyara, Jan 04 '16 at 07:18

score -1 · Answer 1 · answered Jan 04 '16 at 07:18

NSNotificationCenter.defaultCenter().addObserver(self, selector: "methodOfReceivedNotification:", name:"NotificationIdentifier", object: nil)

func methodOfReceivedNotification(notification: NSNotification){
    //Take Action on Notification
}

Add This observer to A ViewController and Create Method.

NSNotificationCenter.defaultCenter().postNotificationName("NotificationIdentifier", object: nil, userInfo:dataDict)

On Button click "post this Notification" from B ViewController. This Will pass controller to "A ViewController" "methodOfReceivedNotification" Method along with "dataDict".

Rushang Prajapati · Answer 2 · 2016-01-04T08:55:17.873

-1

You need to use delegate protocols... Here's how to do it:

Declare a protocol in your secondViewController's header file. It should look like this:

#import <UIKit/UIKit.h>

@protocol SecondDelegate <NSObject>
-(void) secondViewControllerDismissed:(NSString *)stringForFirst
@end

@interface SecondViewController : UIViewController
{
    id                              myDelegate; 
}

@property (nonatomic, assign) id<SecondDelegate>    myDelegate;

Dont forget to synthesize the myDelegate in your .m file:

@synthesize myDelegate;

In your firstViewController's header file subscribe to the SecondDelegate protocol by doing this:

#import "SecondViewController.h"

@interface FirstViewController:UIViewController <SecondDelegate>

Now when you instantiate secondViewController in firstViewController you should do the following:

SecondViewController *second = [[SecondViewController alloc] initWithNibName:nil bundle:nil];

second.myString = @"This text is passed from firstViewController!";

second.myDelegate = self;

second.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;

[self presentModalViewController:second animated:YES];

[second release];

Lastly, in the .m file for your first view controller implement the SecondDelegate's method for secondViewControllerDismissed:

- (void)secondViewControllerDismissed:(NSString *)stringForFirst
{
    NSString *thisIsTheDesiredString = stringForFirst; //And there you have it.....
}

Now when you're about to dismiss the second view controller you want to invoke the method implemented in the first view controller. This part is simple. All you do is, in your second view controller, add some code before the dismiss code:

    if([self.myDelegate respondsToSelector:@selector(secondViewControllerDismissed:)])
{
    [self.myDelegate secondViewControllerDismissed:@"THIS IS THE STRING TO SEND!!!"];
}
[self dismissModalViewControllerAnimated:YES];

Delegate protocols are EXTREMELY, EXTREMELY, EXTREMELY useful. It would do you good to familiarize yourself with them :)

edited Jan 04 '16 at 08:55

answered Jan 04 '16 at 07:18

Rushang Prajapati

586
6
23

Need to call Class B viewcontoller to Class A Viewcontrroller Method. While calling need to pass two string values.@Rushang – Sanju Jan 04 '16 at 07:26
yes follow this step for that make two NSstring *name; NSstring *name2; you can see that in prepare for segue method here i make object of View controllerB so we can access that in there – Rushang Prajapati Jan 04 '16 at 07:28
Value paasing secondary I am asking how to call one method? Into that method I will do some process. – Sanju Jan 04 '16 at 07:30
View controllerB *abc=segue.destinationViewController; abc.name=textfieldname.text; see this line i make object of View controllerB in View controllerA – Rushang Prajapati Jan 04 '16 at 07:33
Check the updated answer and give me sky pe will send the demo – Rushang Prajapati Jan 04 '16 at 07:45
Its not A to B. I am making B to A.@Rushang – Sanju Jan 04 '16 at 08:29
where I want to use this code "instantiate secondViewController" – Sanju Jan 04 '16 at 09:06
Buddy simply and clearly post your answer buddy please. I want to call one method from B to A viewcontroller class. From button click to dismissviewcontroller working That time i need to call and pass value to A viewcotroller method! – Sanju Jan 04 '16 at 09:43
Yes i got it bro and i changed my answer and see this zhttp://stackoverflow.com/questions/6203799/dismissmodalviewcontroller-and-pass-data-back – Rushang Prajapati Jan 04 '16 at 10:08
Nothing code buddy! Just one button on mainviwcontroller If click that button another presentViewController popedup on that I have some tableview cell data select to click submit button need to send mainviewcontroller after receiving that data In this mainviewcontroller will do some JSON process. For that I am asking second viewcontroller Submit button click to dismiss time I need to call first viewcontroller method and passing the value too. Please share some sample If u have! – Sanju Jan 04 '16 at 11:27
Yes i have but wait for some moment – Rushang Prajapati Jan 04 '16 at 11:36
Sure bro Thank you so much your Extream level help!@Rushang – Sanju Jan 04 '16 at 11:37
Buddy Do you have??@Rushang – Sanju Jan 04 '16 at 12:00
wait for 20 min i am not free – Rushang Prajapati Jan 04 '16 at 12:05
Give me sky pe or email – Rushang Prajapati Jan 04 '16 at 12:33
stackios123@gmail.com – Sanju Jan 04 '16 at 12:42
Still I m not receiving buddy? – Sanju Jan 04 '16 at 13:09

How To Call Viewcontroller A Method on dismiss Viewcontroler B Class Using Objective C?

2 Answers2