UITableViewCell's attributes are nil when instantiating UITableView as a popover - ios

Question

I have a UIViewController with a UISegmentedControl from which I'd like to present a UITableViewController as a popover when I click on a segmentedControl segment. The issue I'm having is the moment I click on a segment, the popover starts to load, but crashes as myPopoverTableViewController loads. It crashes in
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell, saying the attributes of my PopoverTableViewCell are nil.
For simplicity's sake, I'll reference my classes here:
myViewController: MyViewController
myPopoverTVController: PopoverTableViewController
myPopoverTVCell: PopoverTableViewCell
In lldb, I checked for the values of the cell, the dataSource, and it seems the only thing that's nil are the the attributes of myPopoverTVCell, which I register in myPopoverTVController's viewWillAppear with the following line:
tableView.register(PopoverTableViewCell.self, forCellReuseIdentifier: "cell")
myPopoverTVController is not connected via a popover segue (though I've tried that) to myViewController. I've checked that I have PopoverTableViewCell referenced in the class for myPopoverTVController's prototype cell. I've double checked the connections from the cell to to the PopoverTableViewCell class. I checked that I've got the Table View Cell's identifier set to cell on the storyboard.
Here's how I begin the popover from myViewController, following Apple's code:
#IBAction func segmentedControlAction(_ sender: UISegmentedControl) {
// instantiate the PopoverTableViewController
let popoverTVC = PopoverTableViewController()
// set variables on it
popoverTVC.selectedSegmentIndex = sender.selectedSegmentIndex
popoverTVC.currentRegion = currentRegion
// disignate presentation style as a popover
popoverTVC.modalPresentationStyle = .popover
present(popoverTVC, animated: true, completion: nil)
let presentationController = UIPopoverPresentationController(presentedViewController: popoverTVC, presenting: self)
presentationController.permittedArrowDirections = .up
presentationController.sourceView = view
presentationController.sourceRect = segmentedControl.frame
}
On myPopoverTVController, here's what my cellForRowAt indexPath looks like:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! PopoverTableViewCell
let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! PopoverTableViewCell
// Configure the cell...
switch selectedSegmentIndex {
case 0, 1:
cell.areaLabel.text = popoverStringArray[indexPath.row]
case 2:
let countryList = locationManager.countryList
let countryCodes = locationManager.countryCodes
cell.areaLabel?.text = countryList[indexPath.row]
cell.flagLabel?.text = countryCodes[indexPath.row]
default:
break
}
return cell
}
I checked the variables that are set upon instantiation on myViewController and they've all got values. It's just the tableViewCell attributes that are nil--lldb returns a memory address for the cell when I type po cell. I've set up UITableViews a million times, but I can't figure this thing out. Any suggestions re: what I'm doing wrong are greatly appreciated. I'll rest assured my problem is a startlingly silly omission on my part. Thank you for reading.

Answer 1

I threw in the towel trying to use Apple's code and figured out an alternative method to get the popover to work.
I ctrl+dragged in storyboard from my myViewController to myPopoverTVController. I set the segue identifier to popoverSegue and set it to display as a popover. I also specified an anchor point.
From there, I gutted the code in segmentedControlAction() to replaced it with the following:
#IBAction func segmentedControlAction(_ sender: UISegmentedControl) {
self.performSegue(withIdentifier: "popoverSegue", sender: segmentedControl.selectedSegmentIndex)
}
I added the following code to my prepareForSegue on myViewController:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "popoverSegue" {
let destinationViewController = segue.destination as! PopoverTableViewController
destinationViewController.selectedSegmentIndex = sender as! Int
destinationViewController.currentRegion = currentRegion
let popoverController = destinationViewController.popoverPresentationController
if popoverController != nil {
popoverController?.delegate = self
}
}
}
I also added a delegate method to myViewController with an extension:
extension MyViewController: UIPopoverPresentationControllerDelegate {
func adaptivePresentationStyle(for controller: UIPresentationController) -> UIModalPresentationStyle {
return .none
}
}
Lastly, I took out a local reference to the data source in myPopoverTVController so it now looks like this:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! PopoverTableViewCell
// Configure the cell...
switch selectedSegmentIndex {
case 0:
cell.areaLabel.text = locationManager.cityList(geographicRegion: currentRegion!)[indexPath.row]
cell.flagLabel.isHidden = true
case 1:
cell.areaLabel.text = locationManager.stateList(geographicRegion: currentRegion!)[indexPath.row]
cell.flagLabel.isHidden = true
case 2:
cell.areaLabel?.text = locationManager.countryList[indexPath.row]
cell.flagLabel?.text = locationManager.countryCodes[indexPath.row].flag()
default:
break
}
return cell
}
...and it worked.
The End ;)