Fetching JSON to ViewController and segue to 2nd ViewController - ios

Question

I have fetched and parsed my Data from API in JSON format to FirstViewController and want to segue to the SecondViewController with the data selected at the concrete person from FirstViewController. The Problem is that I have an API with such example URL: https://www.example.com/api/?action=persons&ln=en which gives me all persons in this format:
[
{
"p_id": "4107",
"p_name": "Name1 Surname1",
"p_role": "Role1",
"general_image": "/imagedb/persons/4107/main/1.jpg"
},{
"p_id": "1978",
"p_name": "Name2 Surname2",
"p_role": "Role2",
"general_image": "/imagedb/persons/1978/main/1.jpg"
}, {...
...}
]
I am showing all these persons in my FirstViewController in CollectionView, which is working correctly, with images, names, roles. But also I need to show my SecondViewController with the data selected in FirstVC. My API for personByID is like this URL: https://www.example.com/api/?action=person&ln=en&personId=1978 which gives me JSON Data in this format:
{
"p_id": "1978",
"p_category": "[2]",
"p_name": "Name2 Surname2",
"p_role": "Role2",
"p_short": null,
"p_text": "long text...",
"p_date_start": "1922.02.05",
"p_date_end": "",
"p_profile_image": "1",
"p_status": "1",
"p_lang": "en",
"general_image": "/imagedb/persons/1978/main/1.jpg",
"photos": [
{
"image_id": "5",
"p_id": "1978",
"lang": "en",
"text": "some text...",
"general": "/imagedb/persons/1978/5.jpg",
"thumbs": "/imagedb/persons/1978/thumb/5.jpg"
},
{
"image_id": "7",
"p_id": "1978",
"lang": "en",
"text": "some text...",
"general": "/imagedb/persons/1978/7.jpg",
"thumbs": "/imagedb/persons/1978/thumb/7.jpg"
}
]
}
This is my Person Struct:
struct Person {
let id: String
let name: String
let role: String
fileprivate let imageURLString: String
var imageURL: URL? {
return URL(string: "https://www.example.com\(imageURLString)")
}
}
extension Person: JSONDecodable {
init(_ decoder: JSONDecoder) throws {
self.id = try decoder.value(forKey: "p_id")
self.name = try decoder.value(forKey: "p_name")
self.role = try decoder.value(forKey: "p_role")
self.imageURLString = try decoder.value(forKey: "general_image")
}
}
This is My FIRST VC:
import UIKit
class PersonListViewController: UIViewController {
#IBOutlet weak var collectionView: UICollectionView!
var personPages: [PagedResult<Person>] = [] {
didSet {
DispatchQueue.main.async {
self.collectionView.reloadData()
}
}
}
override func viewDidLoad() {
super.viewDidLoad()
loadPersons()
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
guard let selectedIndexPath = collectionView.indexPathsForSelectedItems?.first else {
return
}
collectionView.deselectItem(at: selectedIndexPath, animated: animated)
}
var service = ExampleWebService()
private func loadPersons(page: Int = 0, resultsPerPage: Int = 5) {
service.persons(page: page, resultsPerPage: resultsPerPage) { (personPage) in
guard !self.loadedPersonPageNumbers.contains(page) else { return }
self.personPages.append(personPage)
self.updateLastIndexPath(personPage)
}
}
private(set) var lastIndexPath: IndexPath?
private func updateLastIndexPath(_ personPage: PagedResult<Person>) {
if personPage.results.isEmpty {
lastIndexPath = nil
}
else {
lastIndexPath = calculateLastIndexPath()
}
}
private func calculateLastIndexPath() -> IndexPath? {
guard let lastPage = personPages.last else { return nil }
let section = lastPage.pageNumber
let row = lastPage.results.count - 1
return IndexPath(row: row, section: section)
}
fileprivate var loadedPersonPageNumbers: [Int] {
return personPages.map { $0.pageNumber }
}
func person(at indexPath: IndexPath) -> Person? {
guard indexPath.section < personPages.count else {
return nil
}
guard indexPath.row < personPages[indexPath.section].results.count else {
return nil
}
let page = personPages[indexPath.section]
return page.results[indexPath.row]
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
guard let personViewController = segue.destination as? PersonViewController,
let selectedIndexPath = collectionView.indexPathsForSelectedItems?.first else {
return
}
personViewController.person = person(at: selectedIndexPath)
}
#IBAction func exitToPersonsView(segue: UIStoryboardSegue) {
}
}
extension PersonListViewController: UICollectionViewDelegate {
fileprivate var nextPageIndex: Int {
guard let lastPage = personPages.last else {
return 0
}
return lastPage.pageNumber.advanced(by: 1)
}
func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
if indexPath == lastIndexPath {
loadPersons(page: nextPageIndex)
}
}
}
extension PersonListViewController: UICollectionViewDataSource {
func numberOfSections(in collectionView: UICollectionView) -> Int {
return personPages.count
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return personPages[section].results.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell: PersonListCollectionViewCell = collectionView.dequeueReusableCell(withReuseIdentifier: "CollectionViewCell", for: indexPath) as! PersonListCollectionViewCell
cell.person = person(at: indexPath)
return cell
}
}
extension PersonListViewController: UINavigationBarDelegate {
func position(for bar: UIBarPositioning) -> UIBarPosition {
return .topAttached
}
}
And this is My Second VC:
import Foundation
import UIKit
final class PersonViewController: UIViewController {
#IBOutlet weak var imagesCollectionVIew: UICollectionView!
#IBOutlet weak var personRole: UILabel!
#IBOutlet weak var customNavigationBar: UINavigationBar!
var personImagesByID: [PagedResult<Person>] = [] {
didSet {
DispatchQueue.main.async {
self.imagesCollectionVIew.reloadData()
}
}
}
override func viewDidLoad() {
super.viewDidLoad()
loadPersonImagesByID()
}
var person: Person?
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let person = person {
title = person.name
personRole.text = person.role
}
customNavigationBar.topItem?.title = title
}
var service = ExampleWebService()
private func loadPersonImagesByID(page: Int = 0, resultsperPge: Int = 5) {
service.persons(page: page, resultsPerPage: resultsperPge) { (personPage) in
guard !self.loadedPersonPageNumbers.contains(page) else {
return
}
self.personImagesByID.append(personPage)
self.updateLastIndexPath(personPage)
}
}
private(set) var lastIndexPath: IndexPath?
private func updateLastIndexPath(_ personPage: PagedResult<Person>) {
if personPage.results.isEmpty {
lastIndexPath = nil
}
else {
lastIndexPath = calculateLastIndexPath()
}
}
private func calculateLastIndexPath() -> IndexPath? {
guard let lastPage = personImagesByID.last else {
return nil
}
let section = lastPage.pageNumber
let item = lastPage.results.count - 1
return IndexPath(row: item, section: section)
}
fileprivate var loadedPersonPageNumbers: [Int] {
return personImagesByID.map { $0.pageNumber }
}
func person(at indexPath: IndexPath) -> Person? {
guard indexPath.section < personImagesByID.count else {
return nil
}
guard indexPath.item < personImagesByID[indexPath.section].results.count else {
return nil
}
let page = personImagesByID[indexPath.section]
return page.results[indexPath.item]
}
}
extension PersonViewController: UICollectionViewDelegate {
fileprivate var nextPageIndex: Int {
guard let lastPage = personImagesByID.last else {
return 0
}
return lastPage.pageNumber.advanced(by: 1)
}
func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
if indexPath == lastIndexPath {
loadPersonImagesByID(page: nextPageIndex)
}
}
}
extension PersonViewController: UICollectionViewDelegateFlowLayout {
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: self.imagesCollectionVIew.frame.height - 17, height: self.imagesCollectionVIew.frame.height - 17)
}
}
extension PersonViewController: UICollectionViewDataSource {
func numberOfSections(in collectionView: UICollectionView) -> Int {
return personImagesByID.count
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return personImagesByID[section].results.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell: PersonViewCollectionViewCell = collectionView.dequeueReusableCell(withReuseIdentifier: "ImagesCollectionViewCell", for: indexPath) as! PersonViewCollectionViewCell
cell.person = person(at: indexPath)
return cell
}
}
extension PersonViewController: UINavigationBarDelegate {
func position(for bar: UIBarPositioning) -> UIBarPosition {
return .topAttached
}
}
Now my issue is that I am having a problem of how to write correctly my second struct PersonByID and when clicking on the person from First VC to show me data in Second VC from personByID URL Path.