Collection view supplementary view not showing but i had implemented iOS swift

Problem: 

I had registered supplementary view but it was not showing.Also it was not showing error rxswift.

My code as like below.

    func setupRxBinding() {

        //Collection bind

            

        collDataSource = RxCollectionViewSectionedReloadDataSource<SectionOfCollection>(

                configureCell: { (_, collectionView, indexPath, item) in

        // my cell configuration

        })

            

        model.items.bind(to: mycollView.rx.items(dataSource: collDataSource)).disposed(by: disposeBag)

        

        mycollView.rx.itemSelected

            .subscribe(onNext: { [weak self] indexPath in

                

            }).disposed(by: disposeBag)

        mycollView.rx.setDelegate(self).disposed(by: disposeBag)

        collDataSource.configureSupplementaryView = { dataSource, collectionView, kind, indexPath in

            guard kind == UICollectionView.elementKindSectionHeader else {

                fatalError("Unexpected supplementary view kind")

            }

            let headerView = collectionView.dequeueReusableSupplementaryView(

                ofKind: kind,

                withReuseIdentifier: "HeaderCell",

                for: indexPath

            ) as! HeaderCell

            

            return headerView

        }

}

Solution:

Oh.Okay you are code is right.But you have to configureSupplementaryView before binding.Then onnly it will works.

    func setupRxBinding() {

        //Collection bind

            

        collDataSource = RxCollectionViewSectionedReloadDataSource<SectionOfCollection>(

                configureCell: { (_, collectionView, indexPath, item) in

        // my cell configuration

        })

// this code

        collDataSource.configureSupplementaryView = { dataSource, collectionView, kind, indexPath in

            guard kind == UICollectionView.elementKindSectionHeader else {

                fatalError("Unexpected supplementary view kind")

            }

            let headerView = collectionView.dequeueReusableSupplementaryView(

                ofKind: kind,

                withReuseIdentifier: "HeaderCell",

                for: indexPath

            ) as! HeaderCell

            

            return headerView

        }

            

        model.items.bind(to: mycollView.rx.items(dataSource: collDataSource)).disposed(by: disposeBag)

        

        mycollView.rx.itemSelected

            .subscribe(onNext: { [weak self] indexPath in

                

            }).disposed(by: disposeBag)

        mycollView.rx.setDelegate(self).disposed(by: disposeBag)

}

You have to change the code as like above then it will works good..Happy coding....