Dequeue Reusable Cell crashes when calling dequeued cell - ios

Question

I am attempting to have a table view that lists multiple things and allows a user to go through and select multiple cells with checkboxes. My code works up until a certain point, the problem is that the app crashes with the following error
Fatal error: Unexpectedly found nil while unwrapping an Optional value
whenever I call the following code
swift let currentCell = recommendToFriendTableView.cellForRow(at: selectedRow[i]) as? RecommendToFriendsTableViewCell
Here is the method where we set up the cells
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if (tableView == self.friendListTableView) {
let cell: FriendListTableViewCell = tableView.dequeueReusableCell(withIdentifier: "FriendListCell") as! FriendListTableViewCell
let rowNumber = (indexPath as NSIndexPath).row
var name = ""
if searchActive {
name = filtered[rowNumber]
}
else {
name = names[rowNumber]
}
cell.friendNameLabel.text = name
cell.friendNameLabel.backgroundColor = tableViewBgColor
cell.friendNameLabel.textColor = textColor
cell.recommendToFriendButton.layer.borderWidth = 1
cell.recommendToFriendButton.layer.borderColor = tableViewBgColor.cgColor
cell.recommendToFriendButton.layer.cornerRadius = 6
cell.recommendToFriendButton.backgroundColor = buttonBgColor
cell.backgroundColor = tableViewBgColor
//set target for buttons
cell.recommendToFriendButton.tag = rowNumber
cell.recommendToFriendButton.addTarget(self, action:#selector(recommendToFriendButtonClicked), for: UIControl.Event.touchUpInside)
return cell
}
else {
let cell: RecommendToFriendsTableViewCell = tableView.dequeueReusableCell(withIdentifier: "RecommendToFriendsCell") as! RecommendToFriendsTableViewCell
let rowNumber = (indexPath as NSIndexPath).row
// set the content view background color
cell.contentView.backgroundColor = tableViewBgColor
// set the text color
cell.nameLabel.textColor = textColor
var dict_friend = NSMutableDictionary()
if searchActive {
dict_friend = filteredFriendsArray[rowNumber]
}
else {
dict_friend = friendsArray[rowNumber]
}
let name = dict_friend["name"] as! String
cell.nameLabel.text = name
let friendUID = dict_friend["uid"] as! String
cell.friendID = friendUID
let imageAddress = dict_friend["photo"] as? String
if imageAddress != "unavailable" && imageAddress != nil && imageAddress != ""{
//Swift forces us to wrap strings as optional to use them in logic
if let imageURL = imageAddress as String? {
//Swift forces us to wrap strings as optional to use them in logic
if let image = imageURL as String? {
//We convert the string into a URL and get the image
let url = URL(string: image)
URLSession.shared.dataTask(with: url!, completionHandler: { (data, response, error) in
if error != nil {
print(error!)
return
}
//We create a new async thread to download and update the image
DispatchQueue.main.async {
//imageView.image = UIImage(data: data!)
cell.photoImageView.image = UIImage(data:data!)
}
}).resume()
}
} else {
cell.photoImageView!.image = UIImage(named: "placeholder-profile-male.png")
}
} else {
cell.photoImageView!.image = UIImage(named: "placeholder-profile-male.png")
}
cell.checkBoxImageView.image = cell.checkBoxImageView.image!.withRenderingMode(.alwaysTemplate)
cell.checkBoxImageView.tintColor = textColor
// Style the profile photo to show in a circle
cell.photoImageView.layer.borderWidth = 0
cell.photoImageView.layer.borderColor = tableViewBgColor.cgColor
// Set cornerRadius = a square UIImageView frame size width / 2
// In our case, UIImageView height = width = 60 points
cell.photoImageView.layer.cornerRadius = 30
cell.photoImageView.clipsToBounds = true
cell.selectionStyle = .none // to prevent cells from being "highlighted"
return cell
}
}
This is the method where we interact with them. The crash happens on a cellForRow call for a cell that is out of view (aka dequeued)
var firstFriendName: String = ""
var numberOfFriends = 0
if let selectedRow = recommendToFriendTableView.indexPathsForSelectedRows {
numberOfFriends = selectedRow.count
for i in 0..<selectedRow.count {
let currentCell = recommendToFriendTableView.cellForRow(at: selectedRow[i]) as! RecommendToFriendsTableViewCell
let friendID = currentCell.friendID
idList.append(",\(friendID)")
}
let firstSelectedCell = recommendToFriendTableView.cellForRow(at: selectedRow[0]) as! RecommendToFriendsTableViewCell
firstFriendName = firstSelectedCell.nameLabel.text!
After about a day of experimenting, I've yet to figure out the actual problem (other than the observation that it appears to be in regards to calling a dequeued cell)
Any help is appreciated.

Answer 1

When this line
let currentCell = recommendToFriendTableView.cellForRow(at: selectedRow[i]) as! RecommendToFriendsTableViewCell
crashes this means you access a non-visble cell so either use
if let currentCell = recommendToFriendTableView.cellForRow(at: selectedRow[i]) as? RecommendToFriendsTableViewCell { }
or better use the dataSource array of the table to get the data that you want to gran wrongly from the cell