Changing navigation Left Bar button title while selecting collection cell inside a container view

Question

I have a collection view inside a container view. In collection view I have two parts as, UICollectionReusableView and UICollectionViewCell . Inside the UICollectionReusableView again I have a collection view and while selecting a cell from that cell I have to change the LeftNavigationBarTitle. I tried the below code in didSelectItem of collection view but nothing is happen.

navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "cancel-music")?.withRenderingMode(.alwaysOriginal), style: .plain, target: self, action: #selector(self.closeViewTapped)).

I used the above code but it didn't change the navigationButton.

This my storyBoard design.
Is any mistake in my code, please help me to get the exact one. Thankyou.

Answer 1

Create the protocol method for view controller which contains collection view.

Inside HomeFilterVC

protocol HomeFilterVCDelegate: class {
    func collectionViewDidTapped()
}

Then, declare delegate variable like as follow, which will assign to your view controller which contains UIContainerView.

class HomeFilterVC: UIViewController {

    weak var delegate                   : HomeFilterVCDelegate?

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        if let selfDelegate = self.delegate {
            selfDelegate.collectionViewDidTapped()
        }
    }
}

Implement prepare(for segue:, sender:) and HomeFilterVCDelegate methods in HomeVC and update your code as follow.

HomeVC:

class HomeVC: UIViewController {

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

        if segue.identifier == "HomeFilterVC" {

            let collectionVC = segue.destination as! HomeFilterVC
            collectionVC.delegate = self
        }
    }
}

extension HomeVC: HomeFilterVCDelegate {

    func collectionViewDidTapped() {
        navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "cancel-music")?.withRenderingMode(.alwaysOriginal), style: .plain, target: self, action: #selector(self.closeViewTapped)).
    }
} 

I hope this will fix your issue.