[英]How to add TextField to UIAlertController in Swift
我正在嘗試使用UITextView
顯示UIAlertController
。 當我添加該行時:
//Add text field
alertController.addTextFieldWithConfigurationHandler { (textField) -> Void in
}
我收到Runtime
錯誤:
致命錯誤:在解開 Optional 值時意外發現 nil
let alertController: UIAlertController = UIAlertController(title: "Find image", message: "Search for image", preferredStyle: .Alert)
//cancel button
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//cancel code
}
alertController.addAction(cancelAction)
//Create an optional action
let nextAction: UIAlertAction = UIAlertAction(title: "Search", style: .Default) { action -> Void in
let text = (alertController.textFields?.first as! UITextField).text
println("You entered \(text)")
}
alertController.addAction(nextAction)
//Add text field
alertController.addTextFieldWithConfigurationHandler { (textField) -> Void in
textField.textColor = UIColor.greenColor()
}
//Present the AlertController
presentViewController(alertController, animated: true, completion: nil)
這是通過IBAction
在我的ViewController
呈現的。
我已經從這里下載了代碼,它工作正常。 我將該方法復制並粘貼到我的代碼中,但它中斷了。 最后一行self的存在沒有影響。
alert.addTextField { (textField) in
textField.placeholder = "Enter First Name"
}
使用此代碼,我在我的應用程序中成功運行此代碼。
@IBAction func addButtonClicked(sender : AnyObject){
let alertController = UIAlertController(title: "Add New Name", message: "", preferredStyle: UIAlertControllerStyle.Alert)
alertController.addTextFieldWithConfigurationHandler { (textField : UITextField!) -> Void in
textField.placeholder = "Enter Second Name"
}
let saveAction = UIAlertAction(title: "Save", style: UIAlertActionStyle.Default, handler: { alert -> Void in
let firstTextField = alertController.textFields![0] as UITextField
let secondTextField = alertController.textFields![1] as UITextField
})
let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Default, handler: {
(action : UIAlertAction!) -> Void in })
alertController.addTextFieldWithConfigurationHandler { (textField : UITextField!) -> Void in
textField.placeholder = "Enter First Name"
}
alertController.addAction(saveAction)
alertController.addAction(cancelAction)
self.presentViewController(alertController, animated: true, completion: nil)
}
編輯:Swift 3.0 版本
@IBAction func addButtonClicked(_ sender: UIButton){
let alertController = UIAlertController(title: "Add New Name", message: "", preferredStyle: .alert)
alertController.addTextField { (textField : UITextField!) -> Void in
textField.placeholder = "Enter Second Name"
}
let saveAction = UIAlertAction(title: "Save", style: .default, handler: { alert -> Void in
let firstTextField = alertController.textFields![0] as UITextField
let secondTextField = alertController.textFields![1] as UITextField
print("firstName \(firstTextField.text), secondName \(secondTextField.text)")
})
let cancelAction = UIAlertAction(title: "Cancel", style: .default, handler: { (action : UIAlertAction!) -> Void in })
alertController.addTextField { (textField : UITextField!) -> Void in
textField.placeholder = "Enter First Name"
}
alertController.addAction(saveAction)
alertController.addAction(cancelAction)
self.present(alertController, animated: true, completion: nil)
}
要在 Swift 3.0 中添加文本字段:
let alertController = UIAlertController(title: "Title", message: "", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "Save", style: .default, handler: { alert -> Void in
let textField = alertController.textFields![0] as UITextField
// do something with textField
}))
alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
alertController.addTextField(configurationHandler: {(textField : UITextField!) -> Void in
textField.placeholder = "Search"
})
self.present(alertController, animated: true, completion: nil)
解決方案:
斯威夫特 4.2
嘗試以下幾行,看看它是否有效:
let alertController = UIAlertController(title: "Add New Name", message: "", preferredStyle: .alert)
alertController.addTextField { (textField : UITextField!) -> Void in
textField.placeholder = "Enter Second Name"
}
let saveAction = UIAlertAction(title: "Save", style: .default, handler: { alert -> Void in
let firstTextField = alertController.textFields![0] as UITextField
let secondTextField = alertController.textFields![1] as UITextField
})
let cancelAction = UIAlertAction(title: "Cancel", style: .default, handler: nil )
alertController.addTextField { (textField : UITextField!) -> Void in
textField.placeholder = "Enter First Name"
}
alertController.addAction(saveAction)
alertController.addAction(cancelAction)
self.present(alertController, animated: true, completion: nil)
希望能幫助到你。
所以我開始檢查我的代碼與工作代碼可能有什么不同。 我注意到我的 ViewController 擴展了
UITextFieldDelegate
這顯然意味着我需要設置任何子 UITextView 的委托:
alertController.addTextFieldWithConfigurationHandler { (textField) -> Void in
searchTextField = textField
searchTextField?.delegate = self //REQUIRED
searchTextField?.placeholder = "Enter your search terms"
}
如何將 textField 添加到 AlertView? 讓我們保持簡短。
這適用於 Swift 3.0 及更高版本。
var nameField: UITextField?
let alertController = UIAlertController(title: "Add Number", message: nil, preferredStyle: .alert)
// Add textfield to alert view
alertController.addTextField { (textField) in
nameField = textField
}
首先,您實例化UIAlertController
一個對象,然后通過訪問UIAlertController
類的addTextField
成員UIAlertController
添加文本字段。
使用一個 textField 添加 alertController (Swift 5)
func openAlert(){
let alertController = UIAlertController(title: "Title", message: "", preferredStyle: .alert)
alertController.addTextField { (textField : UITextField!) -> Void in
textField.placeholder = "Enter name"
}
let saveAction = UIAlertAction(title: kAlertConfirm, style: .default, handler: { alert -> Void in
if let textField = alertController.textFields?[0] {
if textField.text!.count > 0 {
print("Text :: \(textField.text ?? "")")
}
}
})
let cancelAction = UIAlertAction(title: kAlertCancel, style: .default, handler: {
(action : UIAlertAction!) -> Void in })
alertController.addAction(cancelAction)
alertController.addAction(saveAction)
alertController.preferredAction = saveAction
self.present(alertController, animated: true, completion: nil)
}
對於 Swift 4.0,您可以使用在我的項目中成功測試的代碼示例:
@IBAction func withdrawTapped(_ sender: UIButton) {
let alertController = UIAlertController(title: "Token withdraw", message: "", preferredStyle: .alert)
let withdrawAction = UIAlertAction(title: "Withdraw", style: .default) { (aciton) in
let text = alertController.textFields!.first!.text!
if !text.isEmpty {
self.presentAlert(
title: "Succesful",
message: "You made request for withdraw \(textField.text) tokens")
}
}
let cancelAction = UIAlertAction(title: "Cancel", style: .cancel) { (action) in
}
alertController.addTextField { (textField) in
textField.placeholder = "999"
textField.keyboardType = .decimalPad
}
alertController.addAction(withdrawAction)
alertController.addAction(cancelAction)
self.present(alertController, animated: true, completion: nil)
}
在 Swift 4.2 和 Xcode 10.1 中
使用兩個 Textfields和Read TextField 文本數據發出警報,並在所有視圖的頂部顯示警報。
func alertWithTF(title: String, message: String) {
//Step : 1
let alert = UIAlertController(title: title, message: message, preferredStyle: UIAlertControllerStyle.alert)
//Step : 2
alert.addAction (UIAlertAction(title: "Save", style: .default) { (alertAction) in
let textField = alert.textFields![0]
let textField2 = alert.textFields![1]
if textField.text != "" {
//Read textfield data
print(textField.text!)
print("TF 1 : \(textField.text!)")
} else {
print("TF 1 is Empty...")
}
if textField2.text != "" {
//Read textfield data
print(textField2.text!)
print("TF 2 : \(textField2.text!)")
} else {
print("TF 2 is Empty...")
}
})
//Step : 3
//For first TF
alert.addTextField { (textField) in
textField.placeholder = "Enter your first name"
textField.textColor = .red
}
//For second TF
alert.addTextField { (textField) in
textField.placeholder = "Enter your last name"
textField.textColor = .blue
}
//Cancel action
alert.addAction(UIAlertAction(title: "Cancel", style: .default) { (alertAction) in })
self.present(alert, animated:true, completion: nil)
}
如果您想在所有視圖之上顯示警報。
從上面的代碼中刪除最后一行self.present(alert, animated:true, completion: nil)
並添加以下代碼。
//Present alert on top of all views.
let alertWindow = UIWindow(frame: UIScreen.main.bounds)
alertWindow.rootViewController = UIViewController()
alertWindow.windowLevel = UIWindowLevelAlert + 1
alertWindow.makeKeyAndVisible()
alertWindow.rootViewController?.present(alert, animated:true, completion: nil)
現在這樣調用
alertWithTF(title: "This is title", message: "This is message")
UIAlertController
用UITextfield
在最新的蘋果斯威夫特版本5.1.3
在UIViewController
創建UIAlertController
的lazy
變量,添加UITextFieldDelegate
,在UIButton
Action 上顯示警報:
class YourViewController: UIViewController,UITextFieldDelegate {
//Create Alert Controller Object here
lazy var alertEmailAddEditView:UIAlertController = {
let alert = UIAlertController(title:"My App", message: "Customize Add/Edit Email Pop Up", preferredStyle:UIAlertController.Style.alert)
//ADD TEXT FIELD (YOU CAN ADD MULTIPLE TEXTFILED AS WELL)
alert.addTextField { (textField : UITextField!) in
textField.placeholder = "Enter emails"
textField.delegate = self
}
//SAVE BUTTON
let save = UIAlertAction(title: "Save", style: UIAlertAction.Style.default, handler: { saveAction -> Void in
let textField = alert.textFields![0] as UITextField
print("value entered by user in our textfield is: \(textField.text)")
})
//CANCEL BUTTON
let cancel = UIAlertAction(title: "Cancel", style: UIAlertAction.Style.default, handler: {
(action : UIAlertAction!) -> Void in })
alert.addAction(save)
alert.addAction(cancel)
return alert
}()
//MARK:- UIButton Action for showing Alert Controller
@objc func buttonClicked(btn:UIButton){
self.present(alertEmailAddEditView, animated: true, completion: nil)
}
//MARK:- UITextFieldDelegate
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
textField.resignFirstResponder()
return true
}
}
快樂編碼!! :)
很好的答案,稍作修改以顯示如何使用文本字段:
func addRow (row: Int, bodin: String, flag: Int) {
let alertController = UIAlertController(title: bodin, message: "", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "Save", style: .default, handler: {
alert -> Void in
_ = alertController.textFields![0] as UITextField
}))
alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
alertController.addTextField(configurationHandler: {(textField : UITextField!) -> Void in
switch flag {
case 0:
textField.keyboardType = UIKeyboardType.phonePad
textField.placeholder = "Enter Number"
case 1:
textField.keyboardType = UIKeyboardType.emailAddress
textField.placeholder = "Enter Email"
default:
break
}
})
在 Swift 中將 TextField 添加到 UIAlertController 和 TextField 文本顯示在 UILabel 上
let alert = UIAlertController(title: "Alert", message: "", preferredStyle: .alert)
alert.addTextField { (textField) in
textField.placeholder = "First Name"
}
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: { [weak alert] (_) in
let textField = alert?.textFields![0]
self.label.text = textField?.text }))
self.present(alert, animated: true, completion: nil)
斯威夫特5
第一個類符合 UITextFieldDelegate ,然后創建新的 textField 屬性
private var myTextField : UITextField?
// now where u want to add code
let alertContoller = UIAlertController.init(title: "Add", message: "My message to user", preferredStyle: .alert)
alertContoller.addTextField { (textField) in
// make sure your outside any property should be accessed with self here
self.myTextField = textField
//Important step assign textfield delegate to self
self.myTextField?.delegate = self
self.myTextField?.placeholder = self.textFieldPlaceholderText
}
let action = UIAlertAction.init(title: "Ok", style: .default) { action in
print("Alert tapped")
}
alertContoller.addAction(action)
present(alertContoller, animated: true, completion:nil)
謝謝
private func showLoginAlert() {
let loginAlert = UIAlertController(title: "Login Using Credentials", message: nil, preferredStyle: .alert)
loginAlert.view.tintColor = .systemBlue
loginAlert.addTextField { usernameField in
usernameField.font = .systemFont(ofSize: 17.0)
usernameField.placeholder = "Username"
}
loginAlert.addTextField { passwordField in
passwordField.font = .systemFont(ofSize: 17.0)
passwordField.isSecureTextEntry = true
passwordField.placeholder = "Password"
}
let cancelAction = UIAlertAction(title: "Cancel",
style: .destructive,
handler: { _ in
// self.handleUsernamePasswordCanceled(loginAlert: loginAlert)
})
loginAlert.addAction(cancelAction)
let loginAction = UIAlertAction(title: "Login",
style: .default,
handler: { _ in
// self.handleUsernamePasswordEntered(loginAlert: loginAlert)
})
loginAlert.addAction(loginAction)
loginAlert.preferredAction = loginAction
present(loginAlert, animated: true, completion: nil)
}
斯威夫特 5
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