如何从 UIAlertView 迁移（在 iOS8 中已弃用）
How do I migrate from UIAlertView (deprecated in iOS8)
我目前在我的一个应用程序中有以下代码行。这是一个简单的UIAlertView。但是，从 iOS 8 开始，现在已弃用：
let alertView = UIAlertView(title: "Oops!", message: "This feature isn't available right now", delegate: self, cancelButtonTitle: "OK")
如何更新它以使用 iOS 8+？我相信我必须将某些内容更改为 UIAlertCotroller，但我不太确定是什么。
let alertView = UIAlertView(title: "Oops!", message: "This feature isn't available right now", delegate: self, cancelButtonTitle: "OK")
变成
let alertController = UIAlertController(title: "Oops!", message: "This feature isn't available right now", preferredStyle: .Alert)
let OKAction = UIAlertAction(title: "OK", style: .Default) { (action) in }
alertController.addAction(OKAction)
self.presentViewController(alertController, animated: true) { }
您需要改用 UIAlertController。 To class documentation 非常简单，甚至在文档的开头包含清单 1 中的用法示例（确保它在 ObjC 中而不是在 Swift 中，但它非常相似）。
因此，对于您的用例，它是这样翻译的（添加了注释）：
let alert = UIAlertController(title: "Oops!", message:"This feature isn't available right now", preferredStyle: .alert)
let action = UIAlertAction(title: "OK", style: .default) { _ in
// Put here any code that you would like to execute when
// the user taps that OK button (may be empty in your case if that's just
// an informative alert)
}
alert.addAction(action)
self.presentViewController(alert, animated: true){}
因此紧凑代码如下所示：
let alert = UIAlertController(title: "Oops!", message:"This feature isn't available right now", preferredStyle: .Alert)
alert.addAction(UIAlertAction(title: "OK", style: .Default) { _ in })
self.present(alert, animated: true){}
这里的 self 应该是你的 UIViewController。
附加提示：如果您需要调用在 UIViewController 上下文之外显示警报的代码（其中 self 不是 UIViewController），您可以随时使用您应用的根 VC：
let rootVC = UIApplication.sharedApplication().keyWindow?.rootViewController
rootVC?.presentViewController(alert, animated: true){}
（但一般来说，当你有一个已知的 UIViewController 时最好使用它——而且你通常会显示来自 UIViewControllers 的警报——或者根据你的情况尝试获得最合适的上下文而不是依赖于此技巧）
上面的例子对我帮助不大。我的解决方案适用于 XCode 6.4., Swift 1.2，您可以将此代码复制并粘贴到测试项目中以了解其工作原理：
解决方案 1 - Swift 1.2 :
import UIKit
let ALERT_TITLE = "Got you working, right?"
let ALERT_MESSAGE = "Well maybe..."
class ViewController: UIViewController
{
private var alert: UIAlertController!
private var presentAlertButton: UIButton!
override func viewDidAppear(animated: Bool)
{
/*
// QUICK TEST - 1
self.presentViewController(alert, animated: true, completion: nil)
*/
// QUCIK TEST - 2
/*
let rootVC = UIApplication.sharedApplication().keyWindow?.rootViewController
rootVC?.presentViewController(alert, animated: true, completion: nil)
*/
}
override func viewDidLoad()
{
super.viewDidLoad()
createAndAddAlertV()
createAndAddAlertButton()
}
private func createAndAddAlertV()
{
alert = UIAlertController(title:ALERT_TITLE, message:ALERT_MESSAGE, preferredStyle: .Alert)
let alertAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
alert.addAction(alertAction)
}
private func createAndAddAlertButton()
{
presentAlertButton = UIButton(frame: CGRectMake(
view.frame.size.width / 2,
view.frame.size.height / 2,
200,
100))
presentAlertButton.layer.anchorPoint = CGPointMake(1.0, 1.0)
presentAlertButton.backgroundColor = UIColor.redColor()
presentAlertButton.setTitle("Click For Alert", forState: .Normal)
presentAlertButton.addTarget(self, action: "showAlertV", forControlEvents: .TouchUpInside)
self.view.addSubview(presentAlertButton)
}
@IBAction func showAlertV()
{
println(" Showing... ")
self.presentViewController(alert, animated: true, completion: nil)
}
}
我在 Xcode 7.0 中检查了这个解决方案。有效。 Xcode 进行了一项更改。我再次在 Xcode 6.4 中重新编译它并且它起作用了。 Swift 2.0 的更改如果存在的话应该是很小的。
希望对您有所帮助 ;)
对于那些想知道如何在 Objective-C 中执行此操作的人：
//Step 1: Create a UIAlertController
UIAlertController *myAlertController = [UIAlertController alertControllerWithTitle:@"MyTitle"
message: @"MyMessage"
preferredStyle:UIAlertControllerStyleAlert ];
//Step 2: Create a UIAlertAction that can be added to the alert
UIAlertAction* ok = [UIAlertAction
actionWithTitle:@"OK"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
//Do some thing here, eg dismiss the alertwindow
[myAlertController dismissViewControllerAnimated:YES completion:nil];
}];
//Step 3: Add the UIAlertAction ok that we just created to our AlertController
[myAlertController addAction: ok];
//Step 4: Present the alert to the user
[self presentViewController:myAlertController animated:YES completion:nil];
这将弹出如下所示的警报：
您可以将此代码用于警报视图：
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"Message" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* ok = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
[alertController addAction:ok];
[self presentViewController:alertController animated:YES completion:nil];
对于多个按钮，您可以使用：
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"Message" preferredStyle:UIAlertControllerStyleAlert];
[alertController addAction:[UIAlertAction actionWithTitle:@"Button 1" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self loadGooglrDrive];
}]];
[alertController addAction:[UIAlertAction actionWithTitle:@"Button 2" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self loadDropBox];
}]];
[alertController addAction:[UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self closeAlertview];
}]];
dispatch_async(dispatch_get_main_queue(), ^ {
[self presentViewController:alertController animated:YES completion:nil];
});
-(void)closeAlertview
{
[self dismissViewControllerAnimated:YES completion:nil];
}
我认为这是向后兼容旧 iOS SDK 并在使用较新 SDK 时使用新 API 的方法。此外，在使用已弃用 class 的代码中也没有弃用警告。
if ([UIAlertController class]) {
// Use new API to create alert controller, add action button and display it
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"CityBoard" message:error.errorDescription preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* ok = [UIAlertAction actionWithTitle: @"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {
[alertController dismissViewControllerAnimated:YES completion:nil];
}];
[alertController addAction: ok];
[self presentViewController:alertController animated:YES completion:nil];
} else {
// We are running on old SDK as the new class is not available
// Hide the compiler errors about deprecation and use the class available on older SDK
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"CityBoard"
message:error.errorDescription
delegate:self
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
#pragma clang diagnostic pop
Swift 2.0:
使用 AlertController。
操作示例 Sheet：
let mediaActionSheet: UIAlertController = UIAlertController(title: "Media Action Sheet", message: "Choose an option!", preferredStyle: .ActionSheet)
//Create and add the Cancel action
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//Just dismiss the action sheet
}
mediaActionSheet.addAction(cancelAction)
//Create and add first option action
let takePictureAction: UIAlertAction = UIAlertAction(title: "Take Picture", style: .Default) { action -> Void in
//Code for launching the camera goes here
}
mediaActionSheet.addAction(takePictureAction)
//Create and add a second option action
let choosePictureAction: UIAlertAction = UIAlertAction(title: "Choose From Gallery", style: .Default) { action -> Void in
//Code for picking from gallery goes here
}
mediaActionSheet.addAction(choosePictureAction)
//Present the AlertController
self.presentViewController(mediaActionSheet, animated: true, completion: nil)
警报示例：
1)
let simpleAlert = UIAlertController(title: "Simple Alert", message: "It is just awesome", preferredStyle: UIAlertControllerStyle.Alert);
//show it
showViewController(simpleAlert, sender: self);
2) 带有 TextField 的警报。
let inputTextFieldAlert:UIAlertController = UIAlertController(title: " Input TextField Alert ", message: " Enter on the below TextField ", preferredStyle: UIAlertControllerStyle.Alert);
//default input textField (no configuration...)
inputTextFieldAlert.addTextFieldWithConfigurationHandler(nil);
//no event handler (just close dialog box)
inputTextFieldAlert.addAction(UIAlertAction(title: "No", style: UIAlertActionStyle.Cancel, handler: nil));
//event handler with closure
inputTextFieldAlert.addAction(UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default, handler: {(action:UIAlertAction) in
let fields = inputTextFieldAlert.textFields!;
print("Output: "+fields[0].text!);
}));
presentViewController(inputTextFieldAlert, animated: true, completion: nil);
3)
var alert = UIAlertController(title: "TextField Alert", message: "Enter on the below TextField", preferredStyle: UIAlertControllerStyle.Alert);
//configured input textField
var field:UITextField?;
alert.addTextFieldWithConfigurationHandler({(input:UITextField)in
input.placeholder="Empty Dtaa ;-)";
input.clearButtonMode=UITextFieldViewMode.WhileEditing;
field=input;
});
//YES Handler
func yesHandler(actionTarget: UIAlertAction){
print(field!.text!);
}
//event handler with predefined function
alert.addAction(UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default, handler: yesHandler));
presentViewController(alert, animated: true, completion: nil);
https://github.com/nagibazad/UIAlertControllerWrapper
此包装器提供了一种将 UIAlertView 轻松转换为 UIAlertController 的方法。 UIAlertView 已从 iOS 9.0 中弃用。使用此 UIAlertControllerWrapper 将您的 UIAlertView 旧项目转换为 UIAlertController 保持您的委托实现保持不变，并摆脱所有 UIAlertView 相关的 warnings.
我目前在我的一个应用程序中有以下代码行。这是一个简单的UIAlertView。但是，从 iOS 8 开始，现在已弃用：
let alertView = UIAlertView(title: "Oops!", message: "This feature isn't available right now", delegate: self, cancelButtonTitle: "OK")
如何更新它以使用 iOS 8+？我相信我必须将某些内容更改为 UIAlertCotroller，但我不太确定是什么。
let alertView = UIAlertView(title: "Oops!", message: "This feature isn't available right now", delegate: self, cancelButtonTitle: "OK")
变成
let alertController = UIAlertController(title: "Oops!", message: "This feature isn't available right now", preferredStyle: .Alert)
let OKAction = UIAlertAction(title: "OK", style: .Default) { (action) in }
alertController.addAction(OKAction)
self.presentViewController(alertController, animated: true) { }
您需要改用 UIAlertController。 To class documentation 非常简单，甚至在文档的开头包含清单 1 中的用法示例（确保它在 ObjC 中而不是在 Swift 中，但它非常相似）。
因此，对于您的用例，它是这样翻译的（添加了注释）：
let alert = UIAlertController(title: "Oops!", message:"This feature isn't available right now", preferredStyle: .alert)
let action = UIAlertAction(title: "OK", style: .default) { _ in
// Put here any code that you would like to execute when
// the user taps that OK button (may be empty in your case if that's just
// an informative alert)
}
alert.addAction(action)
self.presentViewController(alert, animated: true){}
因此紧凑代码如下所示：
let alert = UIAlertController(title: "Oops!", message:"This feature isn't available right now", preferredStyle: .Alert)
alert.addAction(UIAlertAction(title: "OK", style: .Default) { _ in })
self.present(alert, animated: true){}
这里的 self 应该是你的 UIViewController。
附加提示：如果您需要调用在 UIViewController 上下文之外显示警报的代码（其中 self 不是 UIViewController），您可以随时使用您应用的根 VC：
let rootVC = UIApplication.sharedApplication().keyWindow?.rootViewController
rootVC?.presentViewController(alert, animated: true){}
（但一般来说，当你有一个已知的 UIViewController 时最好使用它——而且你通常会显示来自 UIViewControllers 的警报——或者根据你的情况尝试获得最合适的上下文而不是依赖于此技巧）
上面的例子对我帮助不大。我的解决方案适用于 XCode 6.4., Swift 1.2，您可以将此代码复制并粘贴到测试项目中以了解其工作原理：
解决方案 1 - Swift 1.2 :
import UIKit
let ALERT_TITLE = "Got you working, right?"
let ALERT_MESSAGE = "Well maybe..."
class ViewController: UIViewController
{
private var alert: UIAlertController!
private var presentAlertButton: UIButton!
override func viewDidAppear(animated: Bool)
{
/*
// QUICK TEST - 1
self.presentViewController(alert, animated: true, completion: nil)
*/
// QUCIK TEST - 2
/*
let rootVC = UIApplication.sharedApplication().keyWindow?.rootViewController
rootVC?.presentViewController(alert, animated: true, completion: nil)
*/
}
override func viewDidLoad()
{
super.viewDidLoad()
createAndAddAlertV()
createAndAddAlertButton()
}
private func createAndAddAlertV()
{
alert = UIAlertController(title:ALERT_TITLE, message:ALERT_MESSAGE, preferredStyle: .Alert)
let alertAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
alert.addAction(alertAction)
}
private func createAndAddAlertButton()
{
presentAlertButton = UIButton(frame: CGRectMake(
view.frame.size.width / 2,
view.frame.size.height / 2,
200,
100))
presentAlertButton.layer.anchorPoint = CGPointMake(1.0, 1.0)
presentAlertButton.backgroundColor = UIColor.redColor()
presentAlertButton.setTitle("Click For Alert", forState: .Normal)
presentAlertButton.addTarget(self, action: "showAlertV", forControlEvents: .TouchUpInside)
self.view.addSubview(presentAlertButton)
}
@IBAction func showAlertV()
{
println(" Showing... ")
self.presentViewController(alert, animated: true, completion: nil)
}
}
我在 Xcode 7.0 中检查了这个解决方案。有效。 Xcode 进行了一项更改。我再次在 Xcode 6.4 中重新编译它并且它起作用了。 Swift 2.0 的更改如果存在的话应该是很小的。
希望对您有所帮助 ;)
对于那些想知道如何在 Objective-C 中执行此操作的人：
//Step 1: Create a UIAlertController
UIAlertController *myAlertController = [UIAlertController alertControllerWithTitle:@"MyTitle"
message: @"MyMessage"
preferredStyle:UIAlertControllerStyleAlert ];
//Step 2: Create a UIAlertAction that can be added to the alert
UIAlertAction* ok = [UIAlertAction
actionWithTitle:@"OK"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
//Do some thing here, eg dismiss the alertwindow
[myAlertController dismissViewControllerAnimated:YES completion:nil];
}];
//Step 3: Add the UIAlertAction ok that we just created to our AlertController
[myAlertController addAction: ok];
//Step 4: Present the alert to the user
[self presentViewController:myAlertController animated:YES completion:nil];
这将弹出如下所示的警报：
您可以将此代码用于警报视图：
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"Message" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* ok = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil];
[alertController addAction:ok];
[self presentViewController:alertController animated:YES completion:nil];
对于多个按钮，您可以使用：
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"Message" preferredStyle:UIAlertControllerStyleAlert];
[alertController addAction:[UIAlertAction actionWithTitle:@"Button 1" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self loadGooglrDrive];
}]];
[alertController addAction:[UIAlertAction actionWithTitle:@"Button 2" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self loadDropBox];
}]];
[alertController addAction:[UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action) {
[self closeAlertview];
}]];
dispatch_async(dispatch_get_main_queue(), ^ {
[self presentViewController:alertController animated:YES completion:nil];
});
-(void)closeAlertview
{
[self dismissViewControllerAnimated:YES completion:nil];
}
我认为这是向后兼容旧 iOS SDK 并在使用较新 SDK 时使用新 API 的方法。此外，在使用已弃用 class 的代码中也没有弃用警告。
if ([UIAlertController class]) {
// Use new API to create alert controller, add action button and display it
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"CityBoard" message:error.errorDescription preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* ok = [UIAlertAction actionWithTitle: @"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {
[alertController dismissViewControllerAnimated:YES completion:nil];
}];
[alertController addAction: ok];
[self presentViewController:alertController animated:YES completion:nil];
} else {
// We are running on old SDK as the new class is not available
// Hide the compiler errors about deprecation and use the class available on older SDK
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"CityBoard"
message:error.errorDescription
delegate:self
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
#pragma clang diagnostic pop
Swift 2.0:
使用 AlertController。
操作示例 Sheet：
let mediaActionSheet: UIAlertController = UIAlertController(title: "Media Action Sheet", message: "Choose an option!", preferredStyle: .ActionSheet)
//Create and add the Cancel action
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//Just dismiss the action sheet
}
mediaActionSheet.addAction(cancelAction)
//Create and add first option action
let takePictureAction: UIAlertAction = UIAlertAction(title: "Take Picture", style: .Default) { action -> Void in
//Code for launching the camera goes here
}
mediaActionSheet.addAction(takePictureAction)
//Create and add a second option action
let choosePictureAction: UIAlertAction = UIAlertAction(title: "Choose From Gallery", style: .Default) { action -> Void in
//Code for picking from gallery goes here
}
mediaActionSheet.addAction(choosePictureAction)
//Present the AlertController
self.presentViewController(mediaActionSheet, animated: true, completion: nil)
警报示例：
1)
let simpleAlert = UIAlertController(title: "Simple Alert", message: "It is just awesome", preferredStyle: UIAlertControllerStyle.Alert);
//show it
showViewController(simpleAlert, sender: self);
2) 带有 TextField 的警报。
let inputTextFieldAlert:UIAlertController = UIAlertController(title: " Input TextField Alert ", message: " Enter on the below TextField ", preferredStyle: UIAlertControllerStyle.Alert);
//default input textField (no configuration...)
inputTextFieldAlert.addTextFieldWithConfigurationHandler(nil);
//no event handler (just close dialog box)
inputTextFieldAlert.addAction(UIAlertAction(title: "No", style: UIAlertActionStyle.Cancel, handler: nil));
//event handler with closure
inputTextFieldAlert.addAction(UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default, handler: {(action:UIAlertAction) in
let fields = inputTextFieldAlert.textFields!;
print("Output: "+fields[0].text!);
}));
presentViewController(inputTextFieldAlert, animated: true, completion: nil);
3)
var alert = UIAlertController(title: "TextField Alert", message: "Enter on the below TextField", preferredStyle: UIAlertControllerStyle.Alert);
//configured input textField
var field:UITextField?;
alert.addTextFieldWithConfigurationHandler({(input:UITextField)in
input.placeholder="Empty Dtaa ;-)";
input.clearButtonMode=UITextFieldViewMode.WhileEditing;
field=input;
});
//YES Handler
func yesHandler(actionTarget: UIAlertAction){
print(field!.text!);
}
//event handler with predefined function
alert.addAction(UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default, handler: yesHandler));
presentViewController(alert, animated: true, completion: nil);
https://github.com/nagibazad/UIAlertControllerWrapper
此包装器提供了一种将 UIAlertView 轻松转换为 UIAlertController 的方法。 UIAlertView 已从 iOS 9.0 中弃用。使用此 UIAlertControllerWrapper 将您的 UIAlertView 旧项目转换为 UIAlertController 保持您的委托实现保持不变，并摆脱所有 UIAlertView 相关的 warnings.