stuartbreckenridge / UISearchControllerWithSwift

This is a small demonstration of the UISearchController API.

UISearchController

This is a small demonstration of the UISearchController API.

Countries.swift

This file contains an array of countries.

To access the array of countries anywhere in the app, you use countries.

ViewController.swift

This class sets up a UISearchController called countrySearchController. The countrySearchController is configured during initialisation:

nil is passed as the argument in the method parameter as it has the effect of presenting the search results in the current view.

lazy var countrySearchController: UISearchController = ({
    /*
        Display search results in a separate view controller
    let storyBoard = UIStoryboard(name: "Main", bundle: Bundle.main)
    let alternateController = storyBoard.instantiateViewController(withIdentifier: "aTV") as! AlternateTableViewController
    let controller = UISearchController(searchResultsController: alternateController)
    */
    let controller = UISearchController(searchResultsController: nil)
    controller.hidesNavigationBarDuringPresentation = false
    controller.dimsBackgroundDuringPresentation = false
    controller.searchBar.searchBarStyle = .minimal
    controller.searchResultsUpdater = self
    controller.searchBar.sizeToFit()
    return controller
})()

In viewDidLoad, the countrySearchController is set as the navigationItem.searchController property. In addition, to make sure that the search bar is always visible, navigationItem.hidesSearchBarWhenScrolling is set to false.

ViewController conforms to the UISearchResultsUpdating protocol.

When the updateSearchResultsForSearchController function is called:

• searchArray is emptied
• a new searchString is created based on the searchBar text, which takes the form of S*E*A*R*C*H*T*E*X*T*
• a search of countries is performed based on searchController.searchBar.text
• any matches are added to searchArray
• countryTable is reloaded

In cellForRowAtIndexPath, the countryTable is populated based on whether or not the searchController is active. If the searchController is active, the cell is configured by calling cell.configureCellWith(searchTerm: String, cellText: String).

SearchTableViewCell.swift

cell.configureCellWith(searchTerm:String, cellText: String) will configure the cell to highlight matched search terms using a basic regular expression.

---

An alternate setup is included that allows you to use a separate view controller to present search results:

A standalone tableViewController is created in Storyboard and then instantiated as part of the UISearchController setup.

lazy var countrySearchController: UISearchController = ({
    // Display search results in a separate view controller
    let storyBoard = UIStoryboard(name: "Main", bundle: Bundle.main)
    let alternateController = storyBoard.instantiateViewController(withIdentifier: "aTV") as! AlternateTableViewController
    let controller = UISearchController(searchResultsController: alternateController)

    //let controller = UISearchController(searchResultsController: nil) 
    controller.hidesNavigationBarDuringPresentation = false
    controller.dimsBackgroundDuringPresentation = false
    controller.searchBar.searchBarStyle = .minimal
    controller.searchResultsUpdater = self
    controller.searchBar.sizeToFit()
    return controller
})()

AlternateTableViewController subscribes to Notifications. When the user enters search a search term, the search results are updated and posted through Notification Center and observed via a didSet:

var searchArray = [String]() {
    didSet {
        NotificationCenter.default.post(name: NSNotification.Name.init("searchResultsUpdated"), object: searchArray)
    }
}