Swift: TextField не обновляется после выбора из UIPickerView

Question

Я создал контроллер, который даст администраторам возможность добавлять новых студентов в базу данных. Я пытаюсь добавить UIPicker в текстовое поле в виде таблицы, в котором используются разные пользовательские ячейки.

UIPicker появляется, когда я выбираю поле, и он также возвращает все данные из моего массива. Проблема в том, что мое текстовое поле НЕ обновляется после выбора чего-либо из UIPicker. Однако простая печать на консоли подтверждает, что выбор работает.

Как правильно отправить свой выбор в текстовое поле, связанное с UIPicker?

class AddStudentInfoController: UITableViewController, UITextFieldDelegate, UIPickerViewDelegate, UIPickerViewDataSource { 

@IBOutlet var addStudentGradeTextField: UITextField! 

var pickerGrade = UIPickerView() 
var allCellsText = [String]() 

let firstNameCell = "firstNameCell" 
let lastNameCell = "lastNameCell" 
let gradeCell = "gradeCell" 

var array = ["First Name", "Last Name", "Grade"] 
var grade = ["--", "One", "Two", "Three"] 

override func viewDidLoad() { 
    super.viewDidLoad() 

    pickerGrade.delegate = self 
    pickerGrade.dataSource = self 
    pickerGrade.backgroundColor = UIColor.white 

    self.tableView.tableFooterView = UIView(frame: CGRect.zero) 
    self.tableView.rowHeight = 60 

    tableView.register(AddStudentFirstNameCell.self, forCellReuseIdentifier: firstNameCell) 
    tableView.register(AddStudentLastNameCell.self, forCellReuseIdentifier: lastNameCell) 
    tableView.register(AddStudentGradeCell.self, forCellReuseIdentifier: gradeCell) 

} 

// Load tableview 
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { 
    return array.count 
} 

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { 

    if indexPath.row == 0 { 
     let cell = tableView.dequeueReusableCell(withIdentifier: firstNameCell, for: indexPath) as! AddStudentFirstNameCell 

     cell.textLabel!.text = self.array[indexPath.row] 
     cell.selectionStyle = UITableViewCellSelectionStyle.none 

     return cell 
    } 

    else if indexPath.row == 1 { 
     let cell = tableView.dequeueReusableCell(withIdentifier: lastNameCell, for: indexPath) as! AddStudentLastNameCell 

     cell.textLabel!.text = self.array[indexPath.row] 
     cell.selectionStyle = UITableViewCellSelectionStyle.none 

     return cell 
    } 

    else { 
     let cell = tableView.dequeueReusableCell(withIdentifier: gradeCell, for: indexPath) as! AddStudentGradeCell 

     cell.textLabel!.text = self.array[indexPath.row] 
     cell.selectionStyle = UITableViewCellSelectionStyle.none 
     cell.addStudentGradeTextField?.inputView = pickerGrade 

     return cell 
    } 
} 

// Picker view 
func textFieldDidBeginEditing(_ textField: UITextField) { 
    pickerGrade.reloadAllComponents() 
    pickerGrade.isHidden = false 
} 

func numberOfComponents(in pickerView: UIPickerView) -> Int { 
    return 1 
} 

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int{ 
    return grade.count 
} 

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) 
{ 
    addStudentGradeTextField?.text = grade[row] 
    self.view.endEditing(true) 
} 

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? { 
    return grade[row] 
} 

// End editing 
func textFieldDidEndEditing(_ textField: UITextField) { 
    allCellsText.append(textField.text!) 
} 
} 

Все мои пользовательские ячейки для таблицы.

// # 
// Custom cells for AddStudent.swift 
// # 
class AddStudentFirstNameCell: UITableViewCell { 

override init(style: UITableViewCellStyle, reuseIdentifier: String?) { 
    super.init(style: .subtitle, reuseIdentifier: reuseIdentifier) 
    setupViews() 
} 

required init?(coder aDecoder: NSCoder) { 
    fatalError("init(coder:) has not been implemented") 
} 

let addStudentTextField: UITextField = { 
    let addStudentTextField = UITextField() 
    addStudentTextField.placeholder = "First Name" 
    addStudentTextField.textColor = .red 
    addStudentTextField.translatesAutoresizingMaskIntoConstraints = false 
    addStudentTextField.rightViewMode = UITextFieldViewMode.always 
    addStudentTextField.autocorrectionType = .no 
    return addStudentTextField 
}() 

func setupViews() { 

    addSubview(addStudentTextField) 

    addStudentTextField.rightAnchor.constraint(equalTo: self.rightAnchor, constant: 10).isActive = true 
    addStudentTextField.centerYAnchor.constraint(equalTo: self.centerYAnchor).isActive = true 
    addStudentTextField.widthAnchor.constraint(equalToConstant: 150).isActive = true 
    addStudentTextField.heightAnchor.constraint(equalToConstant: 48).isActive = true 
} 
} 

class AddStudentLastNameCell: UITableViewCell { 

override init(style: UITableViewCellStyle, reuseIdentifier: String?) { 
    super.init(style: .subtitle, reuseIdentifier: reuseIdentifier) 
    setupViews() 
} 

required init?(coder aDecoder: NSCoder) { 
    fatalError("init(coder:) has not been implemented") 
} 

let addStudentTextField: UITextField = { 
    let addStudentTextField = UITextField() 
    addStudentTextField.placeholder = "Last Name" 
    addStudentTextField.textColor = .red 
    addStudentTextField.translatesAutoresizingMaskIntoConstraints = false 
    addStudentTextField.rightViewMode = UITextFieldViewMode.always 
    addStudentTextField.autocorrectionType = .no 
    return addStudentTextField 
}() 

func setupViews() { 

    addSubview(addStudentTextField) 

    addStudentTextField.rightAnchor.constraint(equalTo: self.rightAnchor, constant: 10).isActive = true 
    addStudentTextField.centerYAnchor.constraint(equalTo: self.centerYAnchor).isActive = true 
    addStudentTextField.widthAnchor.constraint(equalToConstant: 150).isActive = true 
    addStudentTextField.heightAnchor.constraint(equalToConstant: 48).isActive = true 
} 
} 

class AddStudentGradeCell: UITableViewCell { 

override init(style: UITableViewCellStyle, reuseIdentifier: String?) { 
    super.init(style: .subtitle, reuseIdentifier: reuseIdentifier) 
    setupViews() 
} 

required init?(coder aDecoder: NSCoder) { 
    fatalError("init(coder:) has not been implemented") 
} 

let addStudentGradeTextField: UITextField! = { 
    let addStudentGradeTextField = UITextField() 
    addStudentGradeTextField.placeholder = "--" 
    addStudentGradeTextField.textColor = .red 
    addStudentGradeTextField.translatesAutoresizingMaskIntoConstraints = false 
    addStudentGradeTextField.rightViewMode = UITextFieldViewMode.always 
    addStudentGradeTextField.autocorrectionType = .no 
    return addStudentGradeTextField 
}() 

func setupViews() { 

    addSubview(addStudentGradeTextField) 

    addStudentGradeTextField.rightAnchor.constraint(equalTo: self.rightAnchor, constant: 10).isActive = true 
    addStudentGradeTextField.centerYAnchor.constraint(equalTo: self.centerYAnchor).isActive = true 
    addStudentGradeTextField.widthAnchor.constraint(equalToConstant: 150).isActive = true 
    addStudentGradeTextField.heightAnchor.constraint(equalToConstant: 48).isActive = true 
} 
} 

журнал Краш

Starry`@objc AddStudentGradeCell.init(style : UITableViewCellStyle, reuseIdentifier : String?) -> AddStudentGradeCell: 
0x10a402980 <+0>: pushq %rbp 
0x10a402981 <+1>: movq %rsp, %rbp 
0x10a402984 <+4>: subq $0x70, %rsp 
0x10a402988 <+8>: movq %rdi, -0x28(%rbp) 
0x10a40298c <+12>: movq %rcx, %rdi 
0x10a40298f <+15>: movq %rdx, -0x30(%rbp) 
0x10a402993 <+19>: movq %rsi, -0x38(%rbp) 
0x10a402997 <+23>: movq %rcx, -0x40(%rbp) 
0x10a40299b <+27>: callq 0x10a46732a    ; symbol stub for: objc_retain 
0x10a4029a0 <+32>: movq -0x40(%rbp), %rcx 
0x10a4029a4 <+36>: cmpq $0x0, %rcx 
0x10a4029a8 <+40>: sete %r8b 
0x10a4029ac <+44>: xorb $-0x1, %r8b 
0x10a4029b0 <+48>: testb $0x1, %r8b 
0x10a4029b4 <+52>: movq %rax, -0x48(%rbp) 
0x10a4029b8 <+56>: jne 0x10a4029bc    ; <+60> at AddStudent.swift 
0x10a4029ba <+58>: jmp 0x10a4029dc    ; <+92> at AddStudent.swift 
0x10a4029bc <+60>: movq -0x40(%rbp), %rdi 
0x10a4029c0 <+64>: callq 0x10a46747a    ; symbol stub for: static (extension in Foundation):Swift.String._unconditionallyBridgeFromObjectiveC (Swift.Optional<__ObjC.NSString>) -> Swift.String 
0x10a4029c5 <+69>: xorl %esi, %esi 
0x10a4029c7 <+71>: movb %sil, %r8b 
0x10a4029ca <+74>: movq %rcx, -0x50(%rbp) 
0x10a4029ce <+78>: movq %rax, -0x58(%rbp) 
0x10a4029d2 <+82>: movq %rdx, -0x60(%rbp) 
0x10a4029d6 <+86>: movb %r8b, -0x61(%rbp) 
0x10a4029da <+90>: jmp 0x10a4029f9    ; <+121> at AddStudent.swift 
0x10a4029dc <+92>: xorl %eax, %eax 
0x10a4029de <+94>: movl %eax, %ecx 
0x10a4029e0 <+96>: movb $0x1, %dl 
0x10a4029e2 <+98>: movq %rcx, %rsi 
0x10a4029e5 <+101>: movq %rcx, %rdi 
0x10a4029e8 <+104>: movq %rdi, -0x60(%rbp) 
0x10a4029ec <+108>: movq %rcx, -0x50(%rbp) 
0x10a4029f0 <+112>: movq %rsi, -0x58(%rbp) 
0x10a4029f4 <+116>: movb %dl, -0x61(%rbp) 
0x10a4029f7 <+119>: jmp 0x10a4029f9    ; <+121> at AddStudent.swift 
0x10a4029f9 <+121>: movb -0x61(%rbp), %al 
0x10a4029fc <+124>: movq -0x50(%rbp), %rcx 
0x10a402a00 <+128>: movq -0x60(%rbp), %rdx 
0x10a402a04 <+132>: movq -0x58(%rbp), %rsi 
0x10a402a08 <+136>: leaq -0x20(%rbp), %rdi 
0x10a402a0c <+140>: movq %rsi, -0x20(%rbp) 
0x10a402a10 <+144>: movq %rdx, -0x18(%rbp) 
0x10a402a14 <+148>: movq %rcx, -0x10(%rbp) 
0x10a402a18 <+152>: andb $0x1, %al 
0x10a402a1a <+154>: movb %al, -0x8(%rbp) 
0x10a402a1d <+157>: movq -0x30(%rbp), %rcx 
0x10a402a21 <+161>: movq %rdi, -0x70(%rbp) 
0x10a402a25 <+165>: movq %rcx, %rdi 
0x10a402a28 <+168>: movq -0x70(%rbp), %rsi 
0x10a402a2c <+172>: movq -0x28(%rbp), %rdx 
0x10a402a30 <+176>: callq 0x10a402680    ; Starry.AddStudentGradeCell.init (style : __C.UITableViewCellStyle, reuseIdentifier : Swift.Optional<Swift.String>) -> Starry.AddStudentGradeCell at AddStudent.swift:384 
0x10a402a35 <+181>: addq $0x70, %rsp exc_bad_instruction(code=exc_i386_invop,subcode=0x0) 
0x10a402a39 <+185>: popq %rbp 
0x10a402a3a <+186>: retq 

Answer 1

я смог исправить свой код, добавив очень простую строку кода.

Неправильный код:

else { 
    let cell = tableView.dequeueReusableCell(withIdentifier: gradeCell, for: indexPath) as! AddStudentGradeCell 

    cell.textLabel!.text = self.array[indexPath.row] 
    cell.selectionStyle = UITableViewCellSelectionStyle.none 

    cell.addStudentGradeTextField?.inputView = pickerGrade 
    cell.addStudentGradeTextField.placeholder = grade[0] 

    return cell 
} 

Хороший код:

else { 
     let cell = tableView.dequeueReusableCell(withIdentifier: gradeCell, for: indexPath) as! AddStudentGradeCell 

     cell.textLabel!.text = self.array[indexPath.row] 
     cell.selectionStyle = UITableViewCellSelectionStyle.none 

     cell.addStudentGradeTextField.inputView = pickerGrade 
     cell.addStudentGradeTextField.placeholder = grade[0] 

     addStudentGradeTextField = cell.addStudentGradeTextField 

     return cell 
    }