iOS master detail sec - ios

Question

I'm working on a Contacts app which I'm developing using swift. I recently implemented sections and now the detail controller is not working properly. Whenever I click on a contact, it shows details for some other contact. I think the main problem is in prepareforsegue function but I can't figure it out. Help Pls!
//
// ContactListViewController.swift
// TechOriginators
//
// Created by Xcode User on 2017-10-09.
// Copyright © 2017 Xcode User. All rights reserved.
//
import UIKit
import Foundation
class ContactListViewController : UIViewController, UITableViewDataSource, UITableViewDelegate, UISearchResultsUpdating {
#IBOutlet var contactsTableView : UITableView!
var contactViewController: ContactViewController? = nil
var contacts : [Contact] = [] {
didSet{
self.contactsTableView.reloadData()
}
}
//Variables to implement sections in UITableView
var sectionLetters: [Character] = []
var contactsDict = [Character: [String]]()
var contactsName = [String]()
//Search Controller
let searchController = UISearchController(searchResultsController: nil)
//Variable to store filtered contacts through search
var filteredContacts = [Contact]()
//Function to show details of a contact record
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showDetail"{
if let indexPath = contactsTableView.indexPathForSelectedRow{
let object = contacts[indexPath.row]
//let object = contactsDict[sectionLetters[indexPath.section]]![indexPath.row]
let controller = segue.destination as! ContactViewController
controller.detailItem = object
}
}
}
func createDict(){
contactsName = contacts.map{$0.FirstName}
//print(contactsName)
sectionLetters = contactsName.map{ (firstName) -> Character in
return firstName[firstName.startIndex]
}
sectionLetters.sorted()
sectionLetters = sectionLetters.reduce([], { (list, firstName) -> [Character] in
if !list.contains(firstName){
return list + [firstName]
}
return list
})
for entry in contactsName{
if contactsDict[entry[entry.startIndex]] == nil {
contactsDict[entry[entry.startIndex]] = [String]()
}
contactsDict[entry[entry.startIndex]]!.append(entry)
}
for (letter, list) in contactsDict{
contactsDict[letter] = list.sorted()
}
print(sectionLetters)
print(contactsDict)
}
// //Function to load contacts
func loadContacts()
{
self.contacts = getContacts()
}
/*private let session: URLSession = .shared
func loadContacts()
{
//let url = URL(string: "http://127.0.0.1:8080/api/Contacts")!
let url = URL(string: "http://10.16.48.237/api/Contacts")!
let task = session.dataTask(with: url) { (data, response, error) in
print("dataRecieved \(data)")
print("error \(error)")
print ("response \(response)")
guard let data = data else { return }
do {
self.contacts = try parse(data)
}
catch {
print("JSONParsing Error: \(error)")
}
}
task.resume() // firing the task
}*/
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 44
}
func numberOfSections(in tableView: UITableView) -> Int {
return sectionLetters.count
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
if self.searchController.isActive {
return nil
} else {
return String(sectionLetters[section])
}
//return String(sectionLetters[section])
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if searchController.isActive && searchController.searchBar.text != "" {
return filteredContacts.count
}
//return self.contacts.count
print(contactsDict[sectionLetters[section]]!.count)
return contactsDict[sectionLetters[section]]!.count
}
//Function to display cells in UITableView
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell" , for : indexPath)
let contact = contacts[indexPath.row]
let object: Contact
if searchController.isActive && searchController.searchBar.text != ""{
let contact = self.filteredContacts[indexPath.row]
cell.textLabel?.text = contact.FirstName + " " + contact.LastName
}else{
//contact = contactsDict[sectionLetters[indexPath.section]]![indexPath.row]
//cell.textLabel?.text = contact.FirstName + " " + contact.LastName
cell.textLabel?.text = contactsDict[sectionLetters[indexPath.section]]![indexPath.row]
}
return cell
}
//Function to update search results when the user types in search bar
func updateSearchResults(for searchController: UISearchController) {
filterContentForSearchText(searchText: searchController.searchBar.text!)
}
func updateSearchResultsForSearchController(searchController: UISearchController){
filterContentForSearchText(searchText: searchController.searchBar.text!)
}
//Function to find matches for text entered in search bar
func filterContentForSearchText(searchText: String){
filteredContacts = contacts.filter{p in
var containsString = false
if p.FirstName.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.LastName.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.Division.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.Department.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.BusinessNumber.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.HomePhone.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.CellularPhone.lowercased().contains(searchText.lowercased()){
containsString = true
}else if p.Role.lowercased().contains(searchText.lowercased()){
containsString = true
}
return containsString
}
contactsTableView.reloadData()
}
//Function to sorts contacts by First Name
func sortContacts() {
contacts.sort() { $0.FirstName < $1.FirstName }
contactsTableView.reloadData();
}
override func viewDidLoad() {
super.viewDidLoad()
loadContacts()
sortContacts()
searchController.searchResultsUpdater = self
searchController.dimsBackgroundDuringPresentation = false
self.definesPresentationContext = true
createDict()
contactsTableView.tableHeaderView = searchController.searchBar
//contactsTableView.scrollToRow(at: IndexPath(row: 0, section: 0), at: .top, animated: false)
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
//
// ContactViewController.swift
// TechOriginators
//
// Created by Xcode User on 2017-10-09.
// Copyright © 2017 Xcode User. All rights reserved.
//
import UIKit
class ContactViewController: UIViewController {
//#IBOutlet weak var detailDescriptionLabel: UILabel!
#IBOutlet weak var firstNameLabel: UILabel?
#IBOutlet weak var lastNameLabel: UILabel?
#IBOutlet weak var divisionLabel: UILabel?
#IBOutlet weak var departmentLabel: UILabel?
#IBOutlet weak var businessPhoneButton: UIButton?
#IBOutlet weak var homePhoneButton: UIButton?
#IBOutlet weak var cellularPhoneButton: UIButton?
#IBOutlet weak var roleLabel: UILabel?
/*#IBOutlet weak var firstNameLabel: UILabel?
#IBOutlet weak var lastNameLabel: UILabel?
#IBOutlet weak var phoneButton: UIButton?
#IBOutlet weak var emailButton: UIButton?*/
func configureView() {
// Update the user interface for the detail item.
if let detail = self.detailItem {
self.title = detail.FirstName + " " + detail.LastName
firstNameLabel?.text = detail.FirstName
lastNameLabel?.text = detail.LastName
divisionLabel?.text = detail.Division
departmentLabel?.text = detail.Department
businessPhoneButton?.setTitle(detail.BusinessNumber, for: .normal)
homePhoneButton?.setTitle(detail.HomePhone, for: .normal)
cellularPhoneButton?.setTitle(detail.CellularPhone, for: .normal)
roleLabel?.text = detail.Role
}
}
#IBAction func businessPhoneButtonPressed(sender: UIButton){
if let bPhone = detailItem?.BusinessNumber{
if let url = URL(string: "tel://\(bPhone)"), UIApplication.shared.canOpenURL(url){
if #available(iOS 10, *){
UIApplication.shared.open(url)
}else{
UIApplication.shared.openURL(url)
}
}
}
}
#IBAction func homePhoneButtonPressed(sender: UIButton){
if let hPhone = detailItem?.HomePhone{
if let url = URL(string: "tel://\(hPhone)"), UIApplication.shared.canOpenURL(url){
if #available(iOS 10, *){
UIApplication.shared.open(url)
}else{
UIApplication.shared.openURL(url)
}
}
}
}
#IBAction func cellularPhoneButtonPressed(sender: UIButton){
if let cPhone = detailItem?.CellularPhone{
/*if let url = NSURL(string: "tel://\(phone)"){
UIApplication.shared.open(url as URL, options: [:], completionHandler: nil)
}*/
if let url = URL(string: "tel://\(cPhone)"), UIApplication.shared.canOpenURL(url) {
if #available(iOS 10, *) {
UIApplication.shared.open(url)
} else {
UIApplication.shared.openURL(url)
}
}
}
}
/*#IBAction func emailButtonPressed(sender: UIButton){
if let email = detailItem?.email{
if let url = URL(string:"mailto:\(email)"){
UIApplication.shared.open(url as URL)
}
}
}*/
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
configureView()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
var detailItem: Contact? {
didSet {
// Update the view.
self.configureView()
}
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}

Answer 1

I suggest using the same data structure for all your table operations to be consistent. Try populating your dictionary as:
var contactsDict = [Character: [Contact]]()
That way, you can always use the section to find the right array and the row to find the right offset in the array.
Separating the names from the contacts in the table's data is inviting them to get out of synch.