subclass of UIViewController Delegation

Question

So i have 2 view controllers, and a want the DOAbrirListaViewController.h to be a Delegate for the AddTaskViewControoler.h, in theory i think i have everything setup, but the methods on the DOAbrirListaView never get called.

DOAbrirViewController.h

#import "AddTaskViewController.h"


@interface DOAbrirListaViewController : UITableViewController <NSFetchedResultsControllerDelegate, UIAlertViewDelegate, AddTaskViewControllerDelegate>

DOAbrirViewController.m

-(void)addTaskDidCancel {
    NSLog(@"AddTask Did Cancel");

}
-(void)addTaskDidSave {
    NSLog(@"AddTask Did Save");
}

AddTaskViewController.h

@protocol AddTaskViewControllerDelegate

-(void)addTaskDidSave;
-(void)addTaskDidCancel;

@end

@interface AddTaskViewController : UIViewController

@property (nonatomic, weak) id <AddTaskViewControllerDelegate> delegate;
@property (nonatomic, strong) CDMyLists *currentList;


@end

AddTaskViewController.m

- (IBAction)createButton:(id)sender {
    [self.delegate addTaskDidSave];
    NSLog(@"Create Button");
}

- (IBAction)cancelButton:(id)sender {
    [self.delegate addTaskDidCancel];
    NSLog(@"Cancel Button");
}

The buttons are clicked but the NSLOG's on the addTaskDidSave and AddTaskDidCancel, never get called.

Did you set `delegate`? Or is it `nil`? – Aaron Brager Mar 01 '14 at 18:01 — Aaron Brager, Mar 01 '14 at 18:01

Avt · Answer 1 · 2014-03-01T18:03:05.517

0

It seems that delegate is not set properly. Add additional NSLog to cancelButton to check it:

- (IBAction)cancelButton:(id)sender {
    [self.delegate addTaskDidCancel];
    NSLog(@"Cancel Button");
    NSLog(@"self.delegate = %@", self.delegate);
}

edited Mar 01 '14 at 18:03

answered Mar 01 '14 at 17:54

Avt

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score 0 · Answer 2 · answered Mar 01 '14 at 17:58

Did you do the following?

#import "AddTaskViewController.h"

@interface DOAbrirListaViewController : UITableViewController <NSFetchedResultsControllerDelegate, UIAlertViewDelegate, AddTaskViewControllerDelegate>

@property (nonatomic, strong) AddTaskViewController *addTaskController;

in .m file:

_addTaskController = [[AddTaskViewController alloc] init];
[_addTaskController setDelegate:self];

Oleg Sobolev · Answer 3 · 2014-03-01T18:14:30.203

Here is a well working code you need:

definition of DOAbrirListaViewController

@interface DOAbrirListaViewController : UITableViewController <NSFetchedResultsControllerDelegate, UIAlertViewDelegate, AddTaskViewControllerDelegate>

implementation of DOAbrirListaViewController

-(void)viewDidLoad
{
    // set self as a delegate of your taskAddViewController
    [addTaskViewController setDelegate:self];
}

-(void)addTaskDidSaveWithTaskAddViewController:(TaskAddViewController*)taskAddViewController; {
    NSLog(@"AddTask Did Cancel");

}
-(void)addTaskDidCancelWithTaskAddViewController:(TaskAddViewController*)taskAddViewController {
    NSLog(@"AddTask Did Save");
}

definition of AddTaskViewController

@protocol AddTaskViewControllerDelegate;

@interface AddTaskViewController : UIViewController

@property (nonatomic, weak) id <AddTaskViewControllerDelegate> delegate; 
// you need
//a reference
//to the delegate
@property (nonatomic, strong) CDMyLists *currentList;

@end

//So you can transmit your controller to the delegate as a parameter
@protocol AddTaskViewControllerDelegate

-(void)addTaskDidSaveWithTaskAddViewController:(TaskAddViewController*)taskAddViewController;
-(void)addTaskDidCancelWithTaskAddViewController:(TaskAddViewController*)taskAddViewController;

@end

implementation of AddTaskViewController

- (IBAction)createButton:(id)sender 
{
    [self.delegate addTaskDidSaveWithTaskAddViewController:self];
    NSLog(@"Create Button");
}

- (IBAction)cancelButton:(id)sender {
    [self.delegate addTaskDidCancelWithTaskAddViewController:self];
    NSLog(@"Cancel Button");
}

score 0 · Answer 4 · answered Mar 01 '14 at 18:47

The problem was that, i was not setting the delegate, i just need to do that in the prepareForSegue, before performing the Segue.

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    if ([segue.identifier isEqualToString:@"addTask"]) {
        NSLog(@"addTask Segue");

        AddTaskViewController *atvc = (AddTaskViewController *)[segue destinationViewController];
        atvc.delegate = self; // Was missing that
        atvc.currentList = self.currentList;



    }

}

subclass of UIViewController Delegation

4 Answers4