How to link storyboard to view controller - ios

Question

I am trying to connect a storyboard which I made to my view controller file in my chat app.
What I did is...
1) Create a view controller file(swift).
2) Create a storyboard file and set view controller class as a custom class.
3) Connect my component(table view) in my storyboard to a view controller as an outlet.
Now, I got "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value" error message.
Code is the following.
import UIKit
class ChatViewController: UIViewController {
var _device_width: Int = 0
var _device_height: Int = 0
var _footer_size: Int = 0
var _backBtn: UIBarButtonItem!
var window: UIWindow?
var _toolBar: UIToolbar!
var bottomView: ChatRoomInputView!
var chats: [ChatEntity] = []
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
showNavigateBar()
setupUI()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
}
override var canBecomeFirstResponder: Bool {
return true
}
override var inputAccessoryView: UIView? {
return bottomView
}
func showNavigateBar() {
let backButtonItem = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
navigationItem.backBarButtonItem = backButtonItem
self.title = 'My App'
}
}
extension ChatViewController {
func setupUI() {
self.view.backgroundColor = UIColor(red: 113/255, green: 148/255, blue: 194/255, alpha: 1)
// ERROR happen on this line.
// "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value"
tableView.separatorColor = UIColor.clear
tableView.estimatedRowHeight = 10000
tableView.rowHeight = UITableViewAutomaticDimension
tableView.allowsSelection = false
tableView.keyboardDismissMode = .interactive
tableView.register(UINib(nibName: "YourChatViewCell", bundle: nil), forCellReuseIdentifier: "YourChat")
tableView.register(UINib(nibName: "MyChatViewCell", bundle: nil), forCellReuseIdentifier: "MyChat")
let chat1 = ChatEntity(text: "text1", time: "10:01", userType: .I)
let chat2 = ChatEntity(text: "text2", time: "10:02", userType: .You)
let chat3 = ChatEntity(text: "text3", time: "10:03", userType: .I)
chats = [chat1, chat2, chat3]
}
}
extension ChatViewController: UITableViewDataSource {
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.chats.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let chat = self.chats[indexPath.row]
if chat.isMyChat() {
let cell = tableView.dequeueReusableCell(withIdentifier: "MyChat") as! MyChatViewCell
cell.clipsToBounds = true
// Todo: isRead
cell.updateCell(text: chat.text, time: chat.time, isRead: true)
return cell
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "YourChat") as! YourChatViewCell
cell.clipsToBounds = true
cell.updateCell(text: chat.text, time: chat.time)
return cell
}
}
}
extension ChatViewController: UITableViewDelegate {
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print(indexPath)
}
func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
return 10
}
}
And I defined view controller as a custom class.
What should I do to work correct?
Please give me an advice.
ADD)
ChatViewController is called by another class file.
let chatViewController = ChatViewController()
self.navigationController?.pushViewController(chatViewController, animated: false)
And I believe #IBOutlet is connect correctly.
ChatViewController.swift
ChatViewController.storyboard
And I know the tableView is nil when this function was called.
Actually, I don't know much about the storyboard because I usually don't use storyboard. I prefer to create UI by the code. But now, I have to use storyboard file because I want to use a sample project of the chat system.
ADD2)
I think I may mistake the setting of the storyboard. I have no idea how to use navigation controller or entry point on the storyboard.

Answer 1

You should add delegate and datasource in your viewLoad() function.
override func viewDidLoad() {
super.viewDidLoad()
showNavigateBar()
tableView.delegate = self
tableView.dataSource = self
setupUI()
}
If error still exist after that, check your "Outlets" in your Storyboard.

Answer 2

I fixed the problem.
I modified call method.
let storyBoard : UIStoryboard = UIStoryboard(name: "ChatViewController", bundle:nil)
let chatViewController = storyBoard.instantiateViewController(withIdentifier: "ChatViewController")
self.navigationController?.pushViewController(chatViewController, animated: true)
Thank you for your kindness advice.