UISearchController

Syntax

  • UISearchController(searchResultsController: UIViewController?) // Pass nil as the parameter if the search updating controller also displays the searchable content.
  • func updateSearchResults(for searchController: UISearchController) // Required method to implement when adopting the UISearchResultsUpdating protocol

Parameters

ParameterDetails
UISearchController.searchBarThe search bar to install in your interface. (read-only)
UISearchController.searchResultsUpdaterThe object responsible for updating the contents of the search results controller.
UISearchController.isActiveThe presented state of the search interface.
UISearchController.obscuresBackgroundDuringPresentationA Boolean indicating whether the underlying content is obscured during a search.
UISearchController.dimsBackgroundDuringPresentationA Boolean indicating whether the underlying content is dimmed during a search.
UISearchController.hidesNavigationBarDuringPresentationA Boolean indicating whether the navigation bar should be hidden when searching.
UIViewController.definesPresentationContextA Boolean value that indicates whether this view controller's view is covered when the view controller or one of its descendants presents a view controller.
UIViewController.navigationItem.titleViewA custom view displayed in the center of the navigation bar when the receiver is the top item in which a search bar can be placed.
UITableViewController.tableView.tableHeaderViewReturns an accessory view that is displayed above the table in which a search bar can be placed.

Remarks

UIKit Framework Reference:

UISearchController

UISearchResultsUpdating

Implementation

First, make your class comply with the UISearchResultsUpdating protocol.

class MyTableViewController: UITableViewController, UISearchResultsUpdating {}

Add the search controller property:

class MyTableViewController: UTableViewController, UISearchResultsUpdating {
    let searchController = UISearchController(searchResultsController: nil)
}

Add the search bar:

override func viewDidLoad() {
    super.viewDidLoad()

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

And finally, implement the updateSearchResultsForSearchController method that comes from the UISearchResultsUpdating protocol:

func updateSearchResultsForSearchController(searchController: UISearchController) {

}

Search Bar in Navigation Bar Title

This example uses a search controller to filter the data inside a table view controller. The search bar is placed inside the navigation bar that the table view is embedded into.

search-bar-in-nav-bar

Embed a UITableViewController into a UINavigationController to get the UINavigationItem (which contains the navigation bar). Then set our custom ViewController class to inherit from UITableViewController and adopt the UISearchResultsUpdating protocol.

class ViewController: UITableViewController, UISearchResultsUpdating {

    let entries = [(title: "Easiest", image: "green_circle"),
                   (title: "Intermediate", image: "blue_square"),
                   (title: "Advanced", image: "black_diamond"),
                   (title: "Expert Only", image: "double_black_diamond")]
    
    // An empty tuple that will be updated with search results.
    var searchResults : [(title: String, image: String)] = []
    
    let searchController = UISearchController(searchResultsController: nil)

    override func viewDidLoad() {
        super.viewDidLoad()
        
        searchController.searchResultsUpdater = self
        self.definesPresentationContext = true

        // Place the search bar in the navigation item's title view.
        self.navigationItem.titleView = searchController.searchBar

        // Don't hide the navigation bar because the search bar is in it.
        searchController.hidesNavigationBarDuringPresentation = false
    }
    
    func filterContent(for searchText: String) {
        // Update the searchResults array with matches
        // in our entries based on the title value.
        searchResults = entries.filter({ (title: String, image: String) -> Bool in
            let match = title.range(of: searchText, options: .caseInsensitive)
            // Return the tuple if the range contains a match.
            return match != nil
        })
    }

    // MARK: - UISearchResultsUpdating method
    
    func updateSearchResults(for searchController: UISearchController) {
        // If the search bar contains text, filter our data with the string
        if let searchText = searchController.searchBar.text {
            filterContent(for: searchText)
            // Reload the table view with the search result data.
            tableView.reloadData()
        }
    }

    // MARK: - UITableViewController methods
    
    override func numberOfSections(in tableView: UITableView) -> Int { return 1 }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // If the search bar is active, use the searchResults data.
        return searchController.isActive ? searchResults.count : entries.count
    }
    
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        // If the search bar is active, use the searchResults data.
        let entry = searchController.isActive ? 
                    searchResults[indexPath.row] : entries[indexPath.row]
        
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
        cell.textLabel?.text = entry.title
        cell.imageView?.image = UIImage(named: entry.image)
        return cell
    }
}

Search Bar in Table View Header

This example uses a search controller to filter the cells in a table view controller. The search bar is placed inside the header view of the table view. The table view content is offset with the same height as the search bar so that the search bar is hidden at first. Upon scrolling up past the top edge of the table view, the search bar is revealed. Then when the search bar becomes active, it hides the navigation bar.

search-bar-in-table-header-gif search-bar-in-table-header

Embed a UITableViewController into a UINavigationController to get the UINavigationItem (which contains the navigation bar). Then set our custom ViewController class to inherit from UITableViewController and adopt the UISearchResultsUpdating protocol.

class ViewController: UITableViewController, UISearchResultsUpdating {

    let entries = [(title: "Easiest", image: "green_circle"),
                   (title: "Intermediate", image: "blue_square"),
                   (title: "Advanced", image: "black_diamond"),
                   (title: "Expert Only", image: "double_black_diamond")]
    
    // An empty tuple that will be updated with search results.
    var searchResults : [(title: String, image: String)] = []
    
    let searchController = UISearchController(searchResultsController: nil)

    override func viewDidLoad() {
        super.viewDidLoad()
        
        searchController.searchResultsUpdater = self
        self.definesPresentationContext = true

        // Place the search bar in the table view's header.
        self.tableView.tableHeaderView = searchController.searchBar

        // Set the content offset to the height of the search bar's height
        // to hide it when the view is first presented.
        self.tableView.contentOffset = CGPoint(x: 0, y: searchController.searchBar.frame.height)
    }
    
    func filterContent(for searchText: String) {
        // Update the searchResults array with matches
        // in our entries based on the title value.
        searchResults = entries.filter({ (title: String, image: String) -> Bool in
            let match = title.range(of: searchText, options: .caseInsensitive)
            // Return the tuple if the range contains a match.
            return match != nil
        })
    }

    // MARK: - UISearchResultsUpdating method
    
    func updateSearchResults(for searchController: UISearchController) {
        // If the search bar contains text, filter our data with the string
        if let searchText = searchController.searchBar.text {
            filterContent(for: searchText)
            // Reload the table view with the search result data.
            tableView.reloadData()
        }
    }

    // MARK: - UITableViewController methods
    
    override func numberOfSections(in tableView: UITableView) -> Int { return 1 }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // If the search bar is active, use the searchResults data.
        return searchController.isActive ? searchResults.count : entries.count
    }
    
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        // If the search bar is active, use the searchResults data.
        let entry = searchController.isActive ? 
                    searchResults[indexPath.row] : entries[indexPath.row]
        
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
        cell.textLabel?.text = entry.title
        cell.imageView?.image = UIImage(named: entry.image)
        return cell
    }
}

UISerachController in Objective-C

Delegate: UISearchBarDelegate, UISearchControllerDelegate, UISearchBarDelegate

@property (strong, nonatomic)  UISearchController *searchController;

- (void)searchBarConfiguration
{
    self.searchController = [[UISearchController alloc] initWithSearchResultsController:nil];
    self.searchController.searchBar.delegate = self;
    self.searchController.hidesNavigationBarDuringPresentation = NO;
    
    // Hides search bar initially.  When the user pulls down on the list, the search bar is revealed.
    [self.tableView setContentOffset:CGPointMake(0, self.searchController.searchBar.frame.size.height)];
    
    self.searchController.searchBar.backgroundColor = [UIColor DarkBlue];
    self.searchController.searchBar.tintColor = [UIColor DarkBlue];
    
    self.tableView.contentOffset = CGPointMake(0, CGRectGetHeight(_searchController.searchBar.frame));
    self.tableView.tableHeaderView = _searchController.searchBar;
    _searchController.searchBar.delegate = self;
    _searchController.searchBar.showsCancelButton = YES;
    self.tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(resetSearchbarAndTableView)];
    [self.view addGestureRecognizer:self.tapGestureRecognizer];
    
}

- (void)resetSearchbarAndTableView{
// Reload your tableview and resign keyboard.
}


- (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar{
// Search cancelled
}
- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar{
// Implement filtration of your data as per your need using NSPredicate or else.
// then reload your data control like Tableview.
}