ios 使用 Swift 实现 UITextFieldDelegate
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Implementing UITextFieldDelegate with Swift
提问by Beanwah
I have my ViewController class which implements UITextFieldDelegate. I have no auto complete for the funcs such as textFieldShouldBeginEditing. Is this a bug in XCode 6? Here's my class implementation.
我有实现 UITextFieldDelegate 的 ViewController 类。我没有自动完成诸如 textFieldShouldBeginEditing 之类的功能。这是 XCode 6 中的错误吗？这是我的类实现。
class ViewController: UIViewController, UITextFieldDelegate
采纳答案by Jiaaro
Xcode 6 (Beta 1) is not currently supporting autocomplete for non-implemented protocol methods/properties (for Swift).
Xcode 6 (Beta 1) 目前不支持未实现的协议方法/属性（对于 Swift）的自动完成。
Your best bet is to <CMD> - clickon the protocol that isn't yet fully implemented to see what you're missing.
您最好的选择是<CMD> - click在尚未完全实施的协议上查看您缺少的内容。
回答by jayesh kavathiya
class ViewController: UIViewController,UITextFieldDelegate //set delegate to class
@IBOutlet var txtValue: UITextField //create a textfile variable
override func viewDidLoad() {
super.viewDidLoad()
txtValue.delegate = self //set delegate to textfile
}
func textFieldDidBeginEditing(textField: UITextField!) { //delegate method
}
func textFieldShouldEndEditing(textField: UITextField!) -> Bool { //delegate method
return false
}
func textFieldShouldReturn(textField: UITextField!) -> Bool { //delegate method
textField.resignFirstResponder()
return true
}
回答by Kiran K
Swift 3.0.1
// UITextField Delegates
func textFieldDidBeginEditing(_ textField: UITextField) {
}
func textFieldDidEndEditing(_ textField: UITextField) {
}
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
return true;
}
func textFieldShouldClear(_ textField: UITextField) -> Bool {
return true;
}
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
return true;
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
return true;
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder();
return true;
}
回答by DogCoffee
A bit more swifty is ...
更快一点的是......
@IBOutlet weak var nameTF: UITextField! { didSet { nameTF.delegate = self } }
回答by Piyush Mathur
While using Swift Version 3.1 with the outlets of UITextFields, do mark the changes.
将 Swift 3.1 版与 UITextFields 的插座一起使用时，请标记更改。
import UIKit
class LoginViewController: UIViewController, UITextFieldDelegate {
@IBOutlet var txtUserID: UITextField!
@IBOutlet var txtPwd: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
txtUserID.delegate = self
txtPwd.delegate = self
}
// UITextField Delegates
func textFieldDidBeginEditing(_ textField: UITextField) {
print("TextField did begin editing method called")
}
func textFieldDidEndEditing(_ textField: UITextField) {
print("TextField did end editing method called\(textField.text!)")
}
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
print("TextField should begin editing method called")
return true;
}
func textFieldShouldClear(_ textField: UITextField) -> Bool {
print("TextField should clear method called")
return true;
}
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
print("TextField should end editing method called")
return true;
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
print("While entering the characters this method gets called")
return true;
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
print("TextField should return method called")
textField.resignFirstResponder();
return true;
}
}
回答by Ananthu R Krishnan
// MARK:- ---> Textfield Delegates
// MARK:- ---> 文本域代表
func textFieldDidBeginEditing(textField: UITextField) {
print("TextField did begin editing method called")
}
func textFieldDidEndEditing(textField: UITextField) {
print("TextField did end editing method called\(textField.text)")
}
func textFieldShouldBeginEditing(textField: UITextField) -> Bool {
print("TextField should begin editing method called")
return true;
}
func textFieldShouldClear(textField: UITextField) -> Bool {
print("TextField should clear method called")
return true;
}
func textFieldShouldEndEditing(textField: UITextField) -> Bool {
print("TextField should end editing method called")
return true;
}
func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
print("While entering the characters this method gets called")
return true;
}
func textFieldShouldReturn(textField: UITextField) -> Bool {
print("TextField should return method called")
textField.resignFirstResponder();
return true;
}
回答by Giang
Swift 3
斯威夫特 3
@IBOutlet weak var yourNameTextfield: UITextField! {
didSet {
yourNameTextfield.delegate = self
}
}
extension YourNameViewController: UITextFieldDelegate {
func textFieldDidBeginEditing(_ textField: UITextField) {
}
func textFieldDidEndEditing(_ textField: UITextField) {
}
func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
return true
}
func textFieldShouldClear(_ textField: UITextField) -> Bool {
return true
}
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
return true
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
return true
}
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder();
return true
}
}
回答by Jonathan Natie Klopper
I found a little work-around. Just go to file inspector and set type to Objective-C while you are editing the file. Auto-completion presents you Swift options.
我找到了一些解决方法。只需在编辑文件时转到文件检查器并将类型设置为 Objective-C。自动完成为您提供 Swift 选项。
Just switch the type back to Swift when you build.
只需在构建时将类型切换回 Swift。
回答by Giang
Swift 4:
斯威夫特 4：
@IBOutlet weak var yourNameTextField: UITextField! {
didSet {
yourNameTextField.delegate = self
}
}
extension YourNameViewController: UITextFieldDelegate {
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
switch textField {
case yourNameTextField:
yourNameTextField.resignFirstResponder()
default:
break
}
return true
}
func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
return true
}
}
回答by york
In my case by mistake I have added the delegate methods outside of the scope of the class implementation in swift and that restricts the delegate methods to be called.
在我的情况下，我错误地在 swift 类实现范围之外添加了委托方法，这限制了要调用的委托方法。
