I have set up a UITableView in which each cell has a child UIViewController
I've tried reusing cells using dequeueReusableCell(with identifier:) and adding/removing child view controller on willDisplay cell and didEndDisplaying cell methods.
Another thing I preferred using was not dequeuing cells and storing/accessing them like this:
let cell: FeedCell
if let cached = feedCells[feedItem.uuid]{
cell = cached
}else{
cell = Bundle.main.loadNibNamed("FeedCell", owner: nil, options: nil)?.first as! FeedCell
cell.feedItem = feedItem
feedCells[feedItem.uuid] = cell
}
So basically the property feedCells is a dictionary [String: FeedCell], when I was reusing view controllers, it was [String: UIViewController]
I've identified that the key to my issue is this dictionary and didReceiveMemoryWarning
Whenever I receive a memory warning in the app, the visible cells or ViewControllers that are part of that dictionary get removed from view hierarchy even though they hold a strong reference in the dictionary. They do persist to live in the dictionary so I can reload the table view and show them again. Which I'm doing now on didReceiveMemoryWarning.
But my concern is why are the views being removed from the hierarchy like this even though we've held a strong reference to them, and any way to prevent this?
