问题
How can I call func checkField when nextButton is tapped? If no field is empty in ManagedTableEleventhViewController, I'd like to segue to TwelvethViewController.
I have a UIViewController ElevethViewController which holds a container view. The container view has an embed segue to a UITableViewController ManagedTableEleventhViewController. From ElevethViewController there is a Show segue to a UIViewController TwelevethViewController
The View hierarchy looks like this:
ElevethViewController
Container View
ManagedTableEleventhViewController embedded in Container View with Embed segue
Show segue "eleventhToTwelveth" to "Tweleveth View Controller"
Embed segue "myEmbeddedSegue" to "Managed Table"
ManagedTableEleventhViewController contains 4 static cells containing 1 textField each and one empty static cell.
import UIKit
import Foundation
protocol DelegateEleventh {
func checkField(sender:EleventhViewController)
}
class EleventhViewController: UIViewController {
var delegate:DelegateEleventh?
@IBAction func nextButton(_ sender: Any) {
//if delegate is not nil, call func checkField
if let delegateVC = delegate {
delegateVC.checkField(sender:self)
} else{
print("delegateVC value \(delegate)") //prints nil
}
}
} //end of class
import Foundation
import UIKit
class ManagedTableEleventhViewController:
UITableViewController,UITextFieldDelegate,DelegateEleventh {
@IBOutlet weak var fullName: UITextField!
@IBOutlet weak var flatNumber: UITextField!
@IBOutlet weak var streetAddress: UITextField!
@IBOutlet weak var phoneNumber: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
}
//When nextButton is touched in EleventhViewController, call this method
func checkField(sender:EleventhViewController){
for cell in self.tableView.visibleCells {
for sub in cell.contentView.subviews{
if sub is UITextField{
let textF = sub as? UITextField
//if textField is empty, make its border red,else clear
if textF?.text == "" {
self.hasText = false
textF?.layer.cornerRadius = 8.0
textF?.layer.masksToBounds = true
textF?.layer.borderColor = UIColor.red.cgColor
textF?.layer.borderWidth = 1.0
} else {
self.hasText = true
//segue to nextViewcontroller
sender.performSegue(withIdentifier: "elevethToTwelveth", sender: sender)
}
}// end of if sub is UITextField
}//end of for sub in cell.contentView
} //end of for cell in tableView
}
//KEYBOARD DOES NOT RESIGN....
// When tapping outside of the keyboard, close the keyboard down
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
self.view.endEditing(true)
}
// used to check textField has a string value
var hasText:Bool!
//called by ManagedTableEleventhViewController (namely the delegate) when
editing has begun
func textFieldDidBeginEditing(_ textField: UITextField) {
if textField.text == "" {
print("false value in textFieldDidBeginEditing")
self.hasText = false
textField.layer.cornerRadius = 8.0
textField.layer.masksToBounds = true
textField.layer.borderColor = UIColor.red.cgColor
textField.layer.borderWidth = 1.0
} else {
print("true value in textFieldDidBeginEditing")
textField.layer.borderWidth = 1
textField.layer.borderColor = UIColor.white.cgColor
print("call in else")
self.hasText = true
}
}
//called by ManagedTableEleventhViewController (namely the delegate) when
// editing stopped
func textFieldDidEndEditing(_ textField: UITextField, reason: UITextFieldDidEndEditingReason) {
//if textField is empty make the border red
if textField.text == "" {
self.hasText = false
textField.layer.cornerRadius = 8.0
textField.layer.masksToBounds = true
textField.layer.borderColor = UIColor.red.cgColor
textField.layer.borderWidth = 1.0
print("false value in textFieldDidEndEditing")
} else {
textField.layer.borderWidth = 1
textField.layer.borderColor = UIColor.white.cgColor
print("true value in textFieldDidEndEditing")
self.hasText = true
}
}
// Stop Editing on Return Key Tap.
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
}//end of class
回答1:
Thanks to this answer I have obtained the desired result.
class EleventhViewController: UIViewController {
@IBAction func nextButton(_ sender: Any) {
var managed: ManagedTable? {
return self.childViewControllers.last as! ManagedTable?
//if there is no empty field after checkField(sender:_) is called,
// segue to TwelvethViewController
managed?.checkField(sender: self)
}
}
}
class ManagedTableEleventhViewController {
// holds a true value if textField contains a value
var hasText:Bool!
//holds a true/false value for each textField after iterating through them
//with a for loop
var textValues = [Bool]()
//When nextButton is touched in EleventhViewController, call this method
func checkField(sender:EleventhViewController) {
for cell in self.tableView.visibleCells{
for sub in cell.contentView.subviews{
if sub is UITextField{
let textF = sub as? UITextField
//if textField is empty, make its border red,else clear
if textF?.text == "" {
self.hasText = false
self.textValues.append(self.hasText)
textF?.layer.cornerRadius = 8.0
textF?.layer.masksToBounds = true
textF?.layer.borderColor = UIColor.red.cgColor
textF?.layer.borderWidth = 1.0
} else {
self.hasText = true
self.textValues.append(self.hasText)
}
}// end of if sub is UITextField
}//end of for sub in cell.contentView
} //end of for cell in tableView
//if no field is empty perform segue to TwelvethViewController,
//otherwise reset textValues array
if !self.textValues.contains(false){
sender.performSegue(withIdentifier: "eleventhToTwelveth", sender: sender)
}
self.textValues.removeAll()
} //end of checkField(sender:_)
}//end of class
来源：https://stackoverflow.com/questions/42600534/how-to-pass-data-back-to-viewcontroller-holding-container-view-and-tableviewcont