How to remove and add UICollectionView from/to parent view without loading the previous data?

Question

Removing and adding Collection view again with new data but still showing the old data. (Don't need reloading, just need to remove and add collection view again with new data)

Description: The issue goes as follows:

• I am using two Custom Layout Collection Views, reloading and paginating them both.
• Invalidating layout, Reloading and Pagination goes smoothly, no issues in that.
• But in case of switching perspective, say, from QuarterlyView to MonthlyView, i removed the whole collection view from parent view and again show it with new data.
• This is where the problem arises, the new collection view is still showing the old data even after the previously inputed 2D array is replaced with a new one.
• Please note, on switching perspective, I just need to remove and add the collection view with new data, not reloading at all.

This is exactly what I am doing in swift:

func onSwitchingPerspective(url: String) {

headerArray.removeAll() // REMOVED THE HEADER AND CONTENT ARRAY
contentArray.removeAll()

self.customHeaderCollectionView.removeFromSuperview() // REMOVED THE HEADER AND CONTENT COLLECTION VIEWS
self.customContentCollectionView.removeFromSuperview()


DispatchQueue.global(qos: DispatchQoS.QoSClass.default).async { // NEED GLOBAL QUEUE TO CALL API AND LATER UPDATE UI ON MAIN THREAD

(self.headerArray, self.contentArray) = self.getEventsData(URL: url)

DispatchQueue.main.async {

self.showHeaderCollectionView() // ADDED THE COLLECTION VIEWS AGAIN
self.showContentCollectionView()

self.customContentCollectionView.collectionViewLayout.invalidateLayout() // CODE TO RELOAD BOTH THE COLLECTION VIEWS
self.customContentCollectionView.reloadData()
self.customContentCollectionView.scrollToItem(at: IndexPath(row: 0, section: 0), at: .top, animated: false)
self.customHeaderCollectionView.collectionViewLayout.invalidateLayout()
self.customHeaderCollectionView.reloadData()
self.customHeaderCollectionView.scrollToItem(at: IndexPath(row: 0, section: 0), at: .top, animated: false)
}
}
}

Answer 1

Without

self.collectionView.reloadData()

it shows only your previous data.. Its necessary to reload after your

headerArray.removeAll() // REMOVED THE HEADER AND CONTENT ARRAY
contentArray.removeAll()