PickerView will reload by itself with wrong behavior Swift 4.2 - swift

Question

My pickerView was going very well, but don't know why just get wrong behavior after rebuild the project folder.
The component[0] will reload itself but I didn't write any code for it!
Below are the codes:
DropdownListExtension.swift
extension UITextField: UITextFieldDelegate {
func loadAddressDropdownData(data: [String], zipField: UITextField!) {
self.inputView = AddressPickerView(pickerData: data, cityField: self, zipField: zipField)
// ToolBar
let toolBar = UIToolbar()
// Adding Button ToolBar
// ...Init ToolBar
self.inputAccessoryView = toolBar
}
#objc func doneClick() {
self.resignFirstResponder()
}
#objc func cancelClick() {
self.resignFirstResponder()
}
}
AddressPickerView.swift
class AddressPickerView : UIPickerView, UIPickerViewDataSource, UIPickerViewDelegate {
var pickerData : [String]!
var pickerTextField : UITextField!
var zipTextField: UITextField!
var selectedRow = 0
var selectedCity = "臺北市"
init(pickerData: [String], cityField: UITextField, zipField: UITextField) {
super.init(frame: CGRect.zero)
self.pickerData = pickerData
self.pickerTextField = cityField
self.zipTextField = zipField
self.delegate = self
self.dataSource = self
DispatchQueue.main.async{
if pickerData.count > 0 {
self.pickerTextField.text = self.pickerData[0]
} else {
self.pickerTextField.text = nil
}
}
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 2
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
if component == 0{
return pickerData.count
}else {
switch selectedCity{
//...
default:
return 0
}
}
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
if component == 0{
return pickerData[row]
} else {
switch selectedCity{
//...
default:
return ""
}
}
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
print(component)
if component == 0 {
pickerTextField.text = pickerData[row]
selectedRow = row
selectedCity = pickerData[row]
pickerView.reloadComponent(1)
}else {
switch selectedCity{
case "臺北市":
zipTextField.text = taipei[row]
case "基隆市":
zipTextField.text = keelung[row]
//...
default:
return print("")
}
}
}
}
Please help me for fix it, I spent almost 3 das but still cannot figure out the problem...