CODEWITHSUNDEEP
iosobjective-cdelegates
Evgeniy Kleban
Evgeniy Kleban

Reputation: 6940

Delegate method in second ViewController not called

I want to pass data from one of my controller to another. For that purpose i implement delegate in second view controller (it called when use tap "plus" button on first view controller):

Declaration of delegate:

@protocol AddTaskDelegate <NSObject>

-(void)addTask:(NSString*)task byDate:(NSDate*)date;

@end

Implementation of delegate:

- (IBAction)addTask:(id)sender {

    if ([self.addTextField.text length] >0){

        NSDate *now = [NSDate date];

        [self.delegateObj addTask:self.addTextField.text byDate:now];
        [self dismissViewControllerAnimated:YES completion:nil];

    }   else {

        NSLog(@"You should type something");
    }

}

In viewController1:

addController.delegateObj = self;
...

Then:

   -(void)addTask:(NSString *)task byDate:(NSDate *)date  {

    myDateToFill  = date;
    myStringToFill = task;
    NSLog(@"myStringToFill is - %@", task);
    NSLog(@"method called");

}

However, addTask method not called (it suppose to return values calculated in second view controller). What did i miss?

UPDATE:

I update my addTask method for following and figure out my delegate object is nil:

- (IBAction)addTask:(id)sender {

    if ([self.addTextField.text length] >0){

        NSDate *now = [NSDate date];
        NSLog(@"Prepare for repair");

        if (self.delegateObj == nil){
            NSLog(@"ALARM");
        }

        [self.delegateObj customMethod];
        [self.delegateObj taskAdded:self addTask:self.addTextField.text byDate:now];
        [self dismissViewControllerAnimated:YES completion:nil];

    }   else {

        NSLog(@"You should type something");
    }



}

Now in console i can see "Alarm" output, which tell me that self.delegateObj is nil for some reason.

Updated. Solved after that (and removing reference to AddTask controller from implementation):

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

    // Если нету navigation Controller'a

    if ([segue.identifier isEqualToString:@"add"]){

        UINavigationController *navController = [segue destinationViewController];
        AddViewController   *addController = (AddViewController*)([navController viewControllers][0]);
        addController.delegate = self;
    }

}

Upvotes: 1

Views: 341

Answers (1)

casillas
casillas

Reputation: 16793

Have you implemented the following in the ViewController1.h?

@interface ViewController1<AddTaskDelegate>
// ...
@end

and

in the AddTaskDelegate.h, the following line is missing

@property (nonatomic, weak) id <AddTaskDelegate> delegate;

in the AddTaskDelegate.m, add the following

@synthesize delegate;

Additionally, I highly recommend you take a look at the following thread espcially @Tibidabo's answer: How do I create delegates in Objective-C?

Upvotes: 1

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