Displaying Comments Under a Post - ios

Question

I'm new to this and having trouble displaying the comments of a post in a table view with two cells (one cell = post, second cell = comments). Here is my code for the View Controller:
import UIKit
class PostDetailViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
var postId = ""
var post = Post()
var user = User()
var comments = [Comment]()
var users = [User]()
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
print("postId = \(postId)")
loadPost()
loadComments()
}
func loadPost() {
API.Post.observePost(withId: postId) { (post) in
guard let postUid = post.uid else {
return
}
self.fetchUser(uid: postUid, completed: {
self.post = post
self.tableView.reloadData()
})
self.navigationItem.title = post.title
}
}
func fetchUser(uid: String, completed: #escaping () -> Void ) {
API.User.observeUser(withId: uid, completion: {
user in
self.user = user
completed()
})
}
func loadComments() {API.Post_Comment.REF_POST_COMMENTS.child(self.postId).observe(.childAdded, with: {
snapshot in
API.Comment.observeComments(withPostId: snapshot.key, completion: { comment in
self.fetchUser(uid: comment.uid!, completed: {
self.comments.append(comment)
self.tableView.reloadData()
})
})
})
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "Detail_CommentSegue" {
let commentVC = segue.destination as! CommentViewController
let postId = sender as! String
commentVC.postId = postId
}
if segue.identifier == "Detail_ProfileUserSegue" {
let profileVC = segue.destination as! ProfileUserViewController
let userId = sender as! String
profileVC.userId = userId
}
}
}
extension PostDetailViewController: UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return comments.count + 1
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if indexPath.row == 0 {
let cell = tableView.dequeueReusableCell(withIdentifier: "DetailPostCell", for: indexPath) as! DetailTableViewCell
cell.post = post
cell.user = user
cell.delegate = self
return cell
} else {
let commentCell = tableView.dequeueReusableCell(withIdentifier: "Detail_CommentCell") as! CommentTableViewCell
let comment = comments[indexPath.row]
let user = users[indexPath.row]
commentCell.comment = comment
commentCell.user = user
return commentCell
}
}
}
extension PostDetailViewController: DetailTableViewCellDelegate {
func goToCommentVC(postId: String) {
performSegue(withIdentifier: "Detail_CommentSegue", sender: postId)
}
func goToProfileUserVC(userId: String) {
performSegue(withIdentifier: "Detail_ProfileUserSegue", sender: userId)
}
}
The error I'm getting is at:
let comment = comments[indexPath.row]
"fatal error: Index out of range"
There are comments and they appear on the Comments View Controller without issue. I realize the error has something to do with calling two cells but I am unable to figure out a fix.

Answer 1

You are not accounting for the first row when getting a value from your arrays.
The simple fix is to update cellForRowAt as follows:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if indexPath.row == 0 {
let cell = tableView.dequeueReusableCell(withIdentifier: "DetailPostCell", for: indexPath) as! DetailTableViewCell
cell.post = post
cell.user = user
cell.delegate = self
return cell
} else {
let commentCell = tableView.dequeueReusableCell(withIdentifier: "Detail_CommentCell") as! CommentTableViewCell
let comment = comments[indexPath.row - 1] // here
let user = users[indexPath.row - 1] // here
commentCell.comment = comment
commentCell.user = user
return commentCell
}
}
Note the two minor changes marked // here. The idea is that comment[0] is at row 1.
Some better suggestions:
Do not have multiple arrays. Have one array for your data. Define a structure that holds all of the data for one row. Then have one array of those structures. This makes your data easier to handle and makes things like sorting and filtering vastly simpler.
Consider putting your different data in different sections instead of all in one section.