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    <p>First of all, your delegate object property declaration</p> <pre><code>@property (nonatomic, strong) id &lt;PerksDetailsDelegate&gt; delegate; </code></pre> <p>should be changed from <code>strong</code> to <code>weak</code>, since your class doesn't own it.</p> <p>Second, you never set the delegate object for your class. That's the reason why it is <code>nil</code>. My guess is that <code>BarCodeViewController</code> (your <code>PerksDetailsDelegate</code> protocol implementing class) should be an instance variable of the <code>CardDetailsViewController</code> and you missed to set it as a delegate of the <code>perksDetails</code> object in <code>didSelectRowAtIndexPath</code>.</p> <p>Edit.</p> <p>You should have an instance of <code>BarCodeViewController</code> in the <code>CardDetailsViewController</code> class (named <code>bcvController</code>, for the example code below):</p> <p><code>CardDetailsViewController.m</code></p> <pre><code>-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { PerksDetailsViewController *perksDetails = [self.storyboard instantiateViewControllerWithIdentifier:@"detailsOfMyPerks"]; [perksDetails setDelegate:bcvController]; // bcvController should be created before this line [self.navigationController pushViewController:perksDetails animated:YES]; perksDetails.perkDetailsLabel.text = [self.datasource objectAtIndex:indexPath.row]; perksDetails.pointsLabel.text = [self.perks objectForKey:perksDetails.perkDetailsLabel.text]; } </code></pre> <h1>Edit 2</h1> <p>BarCodeViewController.h</p> <pre><code>#import &lt;UIKit/UIKit.h&gt; #import "CardWalletViewController.h" #import "Card.h" #import "PerksDetailsViewController.h" @interface BarcodeViewController : UIViewController &lt;CardWalletDelegate, PerksDetailsDelegate&gt; @property (nonatomic, strong) NSNumber *myPoints; @end </code></pre> <p>BarCodeViewController.m</p> <pre><code>#import "BarcodeViewController.h" // @interface BarcodeViewController () // // @end @implementation BarcodeViewController @synthesize myPoints = _myPoints; - (void)perksDetailsViewController:(PerksDetailsViewController *)sender didPassRequiredPoints:(NSNumber *)requiredPoints { self.myPoints = requiredPoints; } - (void)cardWalletViewController:(CardWalletViewController *)sender withCurrentCard:(Card *)currentCard { Card *myCurrentCard = currentCard; [myCurrentCard.pointsToDeduct addObject:self.myPoints]; NSLog(@"contents :%@", [myCurrentCard.pointsToDeduct description]); } @end </code></pre> <h1>Edit 3</h1> <p>If you want to display a BarcodeViewController, you should use this object's bcvController.</p> <p>CardDetailsViewController.m</p> <pre><code>#import "CardDetailsViewController.h" #import "PerksDetailsViewController.h" #import "Card.h" @implementation CardDetailsViewController @synthesize pointsLabel = _pointsLabel; @synthesize myPoints = _myPoints; @synthesize perks = _perks; @synthesize datasource = _datasource; @synthesize datasourcePoints = _datasourcePoints; @synthesize bcvController = _bcvController; // new instance variable // other functions removed for clarity -(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { PerksDetailsViewController *perksDetails = [self.storyboard instantiateViewControllerWithIdentifier:@"detailsOfMyPerks"]; [perksDetails setDelegate:bcvController]; [self.navigationController pushViewController:perksDetails animated:YES]; perksDetails.perkDetailsLabel.text = [self.datasource objectAtIndex:indexPath.row]; perksDetails.pointsLabel.text = [self.perks objectForKey:perksDetails.perkDetailsLabel.text]; } - (void)viewDidLoad { //show the number of points of the selected Card self.pointsLabel.text = self.myPoints; [self setupArray]; [self setBcvController:[self.storyboard instantiateViewControllerWithIdentifier:@"myBarcodeVC"]]; // use setter to retain object properly [super viewDidLoad]; } </code></pre>
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    1. COThanks! I've already changed it from strong to weak. How do I go about it regarding your second advice? Provide me some sample in your most convenient time.
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    2. COI created bcvController by this, BarcodeViewController *bcvController = [self.storyboard instantiateViewControllerWithIdentifier:@"myBarcodeVC"]; is this one good?
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    3. COI just placed it under the creation of perksDetails. But then upon doing that, an error occurred saying "Sending 'BarCodeViewController *_strong' to parameter of incompatible type 'id<PerksDetailsDelegate>'"
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