Get text from UIPickerview and move Textfield inside UIAlert - ios

Question

Here's an example. I have other alerts with textfields and others with picker views but doing one with both is a pain.
let gradeTypeTextField = gradeTypeTextField (Doesn't work)
var gradeTypeTextField: UITextField!
#IBAction func newGrade(_ sender: AnyObject) {
When button is tapped, show alert.
alertForGrade()
}
var gradeType = ["Attendance", "Assignment", "Homework Assignment", "Quiz", "Test", "Mid-Term", "Exam", "Other"]
override func viewDidLoad() {
super.viewDidLoad()
Hide extra cells
tableView.tableFooterView = UIView()
}
func alertForGrade() {
Create the alert controller.
alert = UIAlertController(title: "New Grade", message: nil, preferredStyle: .alert);
Add the text field. You can configure it however you need.
alert?.addTextField(configurationHandler: { (gradeTypeTextField) -> Void in
gradeTypeTextField.placeholder = "Type of Grade."
let pickerView = UIPickerView()
pickerView.delegate = self
pickerView.dataSource = self
pickerView.backgroundColor = UIColor.white
pickerView.showsSelectionIndicator = true
gradeTypeTextField.inputView = pickerView
self.view.endEditing(true)
})
alert?.addTextField(configurationHandler: { (assignmentTextField) -> Void in
assignmentTextField.placeholder = "Name of the assignment."
})
alert?.addTextField(configurationHandler: { (gradeTextField) -> Void in gradeTextField.placeholder = "Grade for the assignment."
Grab the value from the text field, and print it when the user clicks OK.
let ok = UIAlertAction(title: "OK", style: .default, handler: { (action) -> Void in
let assignmenttextField = (self.alert?.textFields![0])! as UITextField
let gradeTextField = (self.alert?.textFields![1])! as UITextField
let assignment = assignmenttextField.text!
let gradeString = gradeTextField.text!
let grade = Int(gradeString)
self.dictionaryForGradebook.updateValue(grade!, forKey: assignment)
print(self.dictionaryForGradebook)
self.tableView.reloadData()
})
self.alert?.addAction(ok)
self.alert?.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (action) -> Void in
}))
// 4. Present the alert.
self.present(self.alert!, animated: true, completion: nil)
})
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return gradeType.count
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return gradeType[row]
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
This prints but if I try " yearTextField.text = years[row]" it crashes.
print("Testinggggg")
self.view.endEditing(true)
}
Where is the isuue?

Answer 1

You need to be able to reference your created UITextField later when you attempt to add text to it when you select a row in the UIPicker. You seem to be forgetting to place that link:
alert?.addTextField(configurationHandler: { (gradeTypeTextField) -> Void in
// Append this:
self.gradeTypeTextField = gradeTypeTextField
gradeTypeTextField.placeholder = "Type of Grade."
let pickerView = UIPickerView()
pickerView.delegate = self
pickerView.dataSource = self
pickerView.backgroundColor = UIColor.white
pickerView.showsSelectionIndicator = true
gradeTypeTextField.inputView = pickerView
self.view.endEditing(true)
})
This will however create a retain-cycle so it is recommend to create an unowned/weak self link by adding [weak self] to the start of your closure.