Problems while trying to filter dictionary - index out of range error - ios

Question

I have a journal application that has an object called Entry. It has its own Swift file called Entry.swift and these journal entries are saved using arrays of dictionaries.
I added a search bar to the UITableViewController and whenever I input a letter the app crashes after tableView.reloadData() is called. I think this has something to do with the filter returning my array of dictionaries named entries incorrectly and when tableView.reloadData() is called, both of the labels on the dequeueReusableCell can't be populated because the information is in the wrong format in the array of dictionaries.
Entry.swift
//
// Entry.swift
// Journal
//
// Created by handje on 6/17/17.
// Copyright © 2017 Rob Hand. All rights reserved.
//
import Foundation
class Entry {
static fileprivate let titleKey = "title"
static fileprivate let bodyTextKey = "bodyText"
static fileprivate let dateKey = "date"
var title: String
var bodyText: String
var date: String
init(title: String, bodyText: String, date: String ) {
self.title = title
self.bodyText = bodyText
self.date = date
}
func dictionaryRepresentation() -> [String: Any] {
return [Entry.titleKey: title, Entry.bodyTextKey: bodyText, Entry.dateKey: date]
}
convenience init?(dictionary: [String: Any]) {
guard let title = dictionary[Entry.titleKey] as? String,
let bodyText = dictionary[Entry.bodyTextKey] as? String, let date = dictionary[Entry.dateKey] as? String else { return nil
}
self.init(title: title, bodyText: bodyText, date: date)
}
}
extension Entry: Equatable {
static func == (lhs:Entry, rhs:Entry) -> Bool {
return
lhs.title == rhs.title &&
lhs.bodyText == rhs.bodyText
}
}
EntryListTableViewController.swift
//
// EntryListTableViewController.swift
// Journal
//
// Created by handje on 6/17/17.
// Copyright © 2017 Rob Hand. All rights reserved.
//
import UIKit
class EntryListTableViewCell: UITableViewCell {
#IBOutlet weak var dreamTitle: UILabel!
#IBOutlet weak var dreamDate: UILabel!
}
extension EntryListTableViewController: UISearchResultsUpdating {
func updateSearchResults(for searchController: UISearchController) {
filterContentForSearchText(searchText: searchController.searchBar.text!)
}
}
class EntryListTableViewController: UITableViewController {
#IBOutlet weak var searchBar: UISearchBar!
var dreamTitle: UILabel!
let searchController = UISearchController(searchResultsController: nil)
let dreams = EntryController.shared.entries
var filteredDreams = [Entry]()
func filterContentForSearchText(searchText: String, scope: String = "All") {
let filteredDreams = EntryController.shared.entries.filter{ $0.title.contains(searchController.searchBar.text!) }
tableView.reloadData()
print(filteredDreams)
}
override func viewDidLoad() {
//cell setup
super.viewDidLoad()
let backgroundImage = UIImage(named: "DreamPageLucidity.jpg")
let imageView = UIImageView(image: backgroundImage)
imageView.contentMode = .scaleAspectFill
self.tableView.backgroundView = imageView
tableView.separatorInset = .zero
tableView.separatorColor = UIColor.lightGray
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
definesPresentationContext = true
tableView.tableHeaderView = searchController.searchBar
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.tableView.reloadData()
}
// MARK: - Table view data source
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return EntryController.shared.entries.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "entryCell", for: indexPath) as! EntryListTableViewCell
let entry: Entry
if searchController.isActive && searchController.searchBar.text != "" {
entry = filteredDreams[indexPath.row] /////////ERROR HERE///////
} else {
entry = EntryController.shared.entries[indexPath.row]
}
cell.dreamTitle.text = entry.title
cell.dreamDate.text = entry.date
if cell.dreamTitle.text == "" {
cell.dreamTitle.text = "Untitled Dream"
}
return cell
}
override func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete {
let entry = EntryController.shared.entries[indexPath.row]
EntryController.shared.deleteEntry(entry: entry)
tableView.deleteRows(at: [indexPath], with: .fade)
}
}
// MARK: - Navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let detailVC = segue.destination as? EntryDetailViewController
guard let indexPath = tableView.indexPathForSelectedRow else { return }
let entry = EntryController.shared.entries[indexPath.row]
detailVC?.entry = entry
}
}
EntryContoller.swift
//
// EntryController.swift
// Journal
//
// Created by handje on 6/17/17.
// Copyright © 2017 Rob Hand. All rights reserved.
//
import Foundation
class EntryController {
var entries = [Entry]()
static fileprivate let entriesKey = "entriesKey"
static let shared = EntryController()
init() {
load()
}
// MARK: - CRUD
func addNewEntryWith(title: String, bodyText: String, date: String) {
let entry = Entry(title: title, bodyText: bodyText, date: date)
entries.append(entry)
save()
}
func updateEntry(entry: Entry, title: String, bodyText: String, date: String) {
entry.title = title
entry.bodyText = bodyText
save()
}
// Set up search bar
func deleteEntry(entry: Entry) {
guard let index = entries.index(of: entry) else { return }
entries.remove(at: index)
save()
}
// MARK: - save/load UserDefaults
private func save() {
let entryDictionaries = entries.map {$0.dictionaryRepresentation()}
UserDefaults.standard.set(entryDictionaries, forKey: EntryController.entriesKey)
}
private func load() {
guard let entryDictionaries = UserDefaults.standard.object(forKey: EntryController.entriesKey) as? [[String: Any]] else { return }
entries = entryDictionaries.flatMap ({ Entry(dictionary: $0) })
}
}

Answer 1

I think there is a problem with
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return EntryController.shared.entries.count
}
You should put a check here that if search controller is active then return count from filteredDreams else return count from EntryController.shared.entries.count, (make code changes as per your exact implementation) something like:
if searchController.isActive && searchController.searchBar.text != "" {
return filterDreams.count
} else {
return EntryController.shared.entries.count
}

Answer 2

You're returning a list that is bigger than the filtered list in the delegate function numberOfRowsInSection
try this, when searching:
func filterContentForSearchText(searchText: String, scope: String = "All") {
// update the list that is a class property, you were creating a new one
if searchText.isEmpty {
filteredDreams = EntryController.shared.entries
} else {
filteredDreams = EntryController.shared.entries.filter{ $0.title.contains(searchController.searchBar.text!) }
}
tableView.reloadData()
}
in numberOfRowsInSection
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// use the filtered list to determine count
return filteredDreams.count
}
for more safety you can return an empty cell instead of crashing:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard indexPath.row < filteredDreams.count else { return UITableViewCell() }
// your code here
}