Attempting to load the view of a view controller while it is deallocating… UISearchController

Question

I have code that creates a UISearchController' in my UIVIew'sviewDidLoad`.

 self.resultSearchController = ({
        let controller = UISearchController(searchResultsController: nil)
        controller.searchResultsUpdater = self
        controller.searchBar.delegate = self
        controller.dimsBackgroundDuringPresentation = false
        controller.searchBar.sizeToFit()
        controller.hidesNavigationBarDuringPresentation = false //prevent search bar from moving
        controller.searchBar.placeholder = "Search for song"

        self.myTableView.tableHeaderView = controller.searchBar

        return controller

    })()

Right after this closure finishes, this warning appears in the console:

Attempting to load the view of a view controller while it is deallocating is not allowed and may result in undefined behavior (<UISearchController: 0x154d39700>)

I don't get what I am doing wrong. This similar question is not really my situation (At least I don't think so). What is going on?

Answer 1

UISearchController's view has to be removed from its superview before deallocate. (guess it is a bug)

Objective-C...

-(void)dealloc { 
    [searchController.view removeFromSuperview]; // It works!
}

Swift 3...

deinit {
    self.searchController.view.removeFromSuperview()
}

I struggled with this issue for a couple of weeks. ^^

Answer 2

Solved! It was a simple fix. I changed this code

class ViewController: UITableViewController, UISearchResultsUpdating, UISearchBarDelegate {

    var resultSearchController = UISearchController()

to this:

 class ViewController: UITableViewController, UISearchResultsUpdating, UISearchBarDelegate {

    var resultSearchController: UISearchController!

This fixes the problem.

Answer 3

Here is the Swift version that worked for me (similar toJJHs answer):

deinit{
    if let superView = resultSearchController.view.superview
    {
        superView.removeFromSuperview()
    }
}

Answer 4

class SampleClass: UITableViewController, UISearchBarDelegate {

private let searchController =  UISearchController(searchResultsController: nil)

 override func viewDidLoad() {
        super.viewDidLoad()

        searchController.loadViewIfNeeded() // Add this line before accessing searchController
 }

}

Answer 5

Hacking together a few solutions I managed to get mine working by adding lines to viewDidLoad before fully setting up the UISearchController:

override func viewDidLoad() {
    super.viewDidLoad()
    self.navigationItem.rightBarButtonItem = self.editButtonItem()

    if #available(iOS 9.0, *) {
        self.resultSearchController.loadViewIfNeeded()// iOS 9
    } else {
        // Fallback on earlier versions
        let _ = self.resultSearchController.view          // iOS 8
    }
    self.resultSearchController = ({
        let controller = UISearchController(searchResultsController: nil)
        controller.searchResultsUpdater = self
        controller.dimsBackgroundDuringPresentation = false
        controller.searchBar.sizeToFit()

        self.tableView.tableHeaderView = controller.searchBar

        return controller
    })()

    self.tableView.reloadData()

}

Answer 6

In Swift2 I got the same error message due to an obvious bug:

let alertController = UIAlertController(title: "Oops",
    message:"bla.", preferredStyle: UIAlertControllerStyle.Alert)

alertController.addAction(UIAlertAction(title: "Ok", 
     style: UIAlertActionStyle.Default,handler: nil))

self.presentViewController(alertController, animated: true, completion: nil)

Due to a stupid copy error from myself, I had not included the self.presentViewController line. This caused the same error.

Answer 7

In Swift 2.2 version that worked for me

deinit {
    self.searchController?.view.removeFromSuperview()
}

I think it's helpful!

Answer 8

Mine is working like this

func initSearchControl(){

        searchController = UISearchController(searchResultsController: nil)

        if #available(iOS 9.0, *) {
            searchController.loadViewIfNeeded()
        } else {
            let _ = self.searchController.view
        }

        searchController.searchResultsUpdater = self
        searchController.dimsBackgroundDuringPresentation = false
        definesPresentationContext = true
        tableView.tableHeaderView = searchController.searchBar
        searchController.searchBar.sizeToFit()
    }

searchController.loadViewIfNeeded() solves the problem but you need to call it after initializing the searchController

Answer 9

Creating a search controller in viewDidLoad() and setting its search bar as the navigation item's title view doesn't create a strong reference to the search controller, which is why it's deallocated.

So instead of doing this:

override func viewDidLoad() {
    super.viewDidLoad()
    // Create search controller
    let searchController = UISearchController(searchResultsController: nil)
    // Add search bar to navigation bar
    navigationItem.titleView = searchController.searchBar
    // Size search bar
    searchController.searchBar.sizeToFit()
}

You should do this:

var searchController: UISearchController!

override func viewDidLoad() {
    super.viewDidLoad()
    // Create search controller
    searchController = UISearchController(searchResultsController: nil)
    // Add search bar to navigation bar
    navigationItem.titleView = searchController.searchBar
    // Size search bar
    searchController.searchBar.sizeToFit()
}

Answer 10

I used Derek's answer, but had to change it slightly. The answer that was provided crashed for me because the call to loadViewIfNeeded() happened before the resultSearchController was defined. (My declaration was

var resultSearchController: UISearchController!

). So I just moved it afterwards and it worked.

If I left out the call entirely, the bug remained, so I'm sure it is an essential part of the answer. I was unable to test it on iOS 8.

Answer 11

It's not a bug. It seems that you have to avoid creating ViewControllers without presenting them. So after SomeViewController() or let variable: SomeViewController you have to call something like this self.presentViewController(yourViewController ...etc). If you don't do that, you will get this warning when this view controller will be dealocated.

Answer 12

It seem the view is lazy loaded, if you allocated the controller and never show it, the view is not loaded. In this case, if the controller is deallocated, you will received this warning. you could show it once, or call it's loadViewIfNeed() method, or use 'let _ = controller.view' to force load the view to avoid this warning.

Answer 13

I'm a bit late to the party, but here's my solution:

var resultSearchController: UISearchController!

override func viewDidLoad()
{
    super.viewDidLoad()

    self.resultSearchController = ({
        let searchController = UISearchController(searchResultsController: nil)
        searchController.searchResultsUpdater = self
        searchController.dimsBackgroundDuringPresentation = false
        searchController.searchBar.sizeToFit()
        return searchController
    })()

    self.tableView.tableHeaderView = self.resultSearchController.searchBar
    self.tableView.reloadData()
}

I hope it works for you.