index out of range UISearchController - ios

Question

I am trying to obtain the behaviour you find in whatsapp when trying to Add Participants to a group. In a tableView I have implemented UISearchController.
When a new row is selected in tableView, it is assigned an filled image(see screenshot below) and it is added/deleted to/from selectedUsers. When I start searching in the searchBar cells get rearranged and I get index out of range error, which is normal. I don't know where to go from here.
Scope:
allow the user to add/remove users whether searchBar is active or not
make sure there are no duplicate users in selectedUsers. This will be saved to DataBase.
remove cancel button that is attached on searchBar.
What have I tried?
class GroupRegistrationViewController: UITableViewController {
let searchController = UISearchController(searchResultsController: nil)
var usersArray = [User]() //users that currentUser is following
var currentUser: User!
var selectedUsers = [User]() //selected users in this controller, selected users we follow
var filteredUsers = [User]() //this property will hold the Users that the currentUser is searching for
override func viewDidLoad() {
super.viewDidLoad()
self.fetchUsers()
navigationItem.title = "GroupRegistration"
navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
definesPresentationContext = true
tableView.tableHeaderView = searchController.searchBar
searchController.searchBar.placeholder = "Search Members"
searchController.hidesNavigationBarDuringPresentation = false
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//simply check whether the user is searching or not
if isFiltering() {
return filteredUsers.count
}
return usersArray.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "GroupRegistrationTableViewCell") as! GroupRegistrationTableViewCell
if isFiltering() {
cell.user = filteredUsers[indexPath.row]
}else{
cell.user = usersArray[indexPath.row]
}
if selectedUsers.contains(cell.user) {
//User type conforms to Equatable protocol so check is allowed
cell.added = true
}
return cell
}
//this method determines if you are currently filtering results or not
func isFiltering() -> Bool {
return searchController.isActive && !searchBarIsEmpty()
}
func searchBarIsEmpty() -> Bool {
return searchController.searchBar.text?.isEmpty ?? true
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let cell = tableView.cellForRow(at: indexPath) as! GroupRegistrationTableViewCell
cell.added = !cell.added
if cell.added == true {
self.addRecipient(user: cell.user)
}else{
let index = selectedUsers.index(of: cell.user)!
self.deleteRecipient(user: cell.user, index: index)
}
}
// - Helper methods
// - add
// - delete
func addRecipient(user: User) {
self.selectedUsers.append(user)
}
func deleteRecipient(user: User, index: Int) {
selectedUsers.remove(at: index)
}
}//end of class
extension GroupRegistrationViewController {
//get users from firebase
func fetchUsers() {
DatabaseReference.users(uid: currentUser.userUID).reference().child("follows").observe(.childAdded, with: { (snapshot) in
let user = User(dictionary: snapshot.value as! [String:Any])
self.usersArray.insert(user, at: 0)
let indexPath = IndexPath(row: 0, section: 0)
self.tableView.insertRows(at: [indexPath], with: .fade)
})
}
}
//UISearchResultsUpdating Delegate
extension GroupRegistrationViewController: UISearchResultsUpdating {
func filteredContentForSearchText(searchText: String, scope: String = "All") {
filteredUsers = usersArray.filter({ (user) -> Bool in
return user.fullName.lowercased().contains(searchText.lowercased())
})
tableView.reloadData()
}
/*
whenever the user adds or removes text in the search bar, the UISearchController will inform the GroupRegistrationViewController class of the change via a call to updateSearchResults(for:), which in turn calls filterContentForSearchText(_:scope:).
*/
func updateSearchResults(for searchController: UISearchController) {
filteredContentForSearchText(searchText: searchController.searchBar.text!)
searchController.searchBar.showsCancelButton = false
//CancelButton shows up when I tap for the first time in the search bar. !!!! - not desired behaviour.
//CancelButton disapears when I start typing
}
}
`class GroupRegistrationTableViewCell: UITableViewCell {`
#IBOutlet weak var profileImageView: UIImageView!
#IBOutlet weak var displayNameLabel: UILabel!
#IBOutlet weak var checkboxImageView: UIImageView!
#IBOutlet weak var fullNameTextLabel: UILabel!
var user: User! {
didSet {
self.updateUI()
}
}
//when a row is selected added property is assigned true/false value
var added: Bool = false {
didSet{
if added == false {
checkboxImageView.image = UIImage(named: "icon-checkbox")
}else {
checkboxImageView.image = UIImage(named: "icon-checkbox-filled")
}
}
}
//add cache here
var cache = SAMCache.shared()
func updateUI() {
let profilePictureKey = "\(user.userUID)-profilePicture"
if let image = cache?.image(forKey: profilePictureKey){
self.profileImageView.image = image
self.profileImageView.layer.cornerRadius = self.profileImageView.bounds.width / 2.0
self.profileImageView.layer.masksToBounds = true
} else {
user.downloadProfilePicture { (image, error) in
self.cache?.setImage(image, forKey: profilePictureKey)
self.profileImageView.image = image
self.profileImageView.layer.cornerRadius = self.profileImageView.bounds.width / 2.0
self.profileImageView.layer.masksToBounds = true
}
}
displayNameLabel.text = user.username
checkboxImageView.image = UIImage(named: "icon-checkbox")
fullNameTextLabel.text = user.fullName
}
`}//end of class`