点击 UIAlertController 外部时如何关闭 UIAlertController？

Question

当点击

UIAlertController

之外时如何消除

UIAlertController

？

我可以添加

UIAlertAction

样式的

UIAlertActionStyleCancel

来消除

UIAlertController

。

但我想添加一个功能，当用户点击

UIAlertController

之外时，

UIAlertController

将关闭。怎么做呢？谢谢你。

Answer 1

如果您的目标设备具有 iOS > 9.3 并使用 Swift 并且首选样式是 Alert 您可以使用如下代码片段：

func showAlertBtnClicked(sender: UIButton) {
    let alert = UIAlertController(title: "This is title", message: "This is message", preferredStyle: .Alert)
    self.presentViewController(alert, animated: true, completion:{
        alert.view.superview?.userInteractionEnabled = true
        alert.view.superview?.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.alertControllerBackgroundTapped)))
    })
}

func alertControllerBackgroundTapped()
{
    self.dismissViewControllerAnimated(true, completion: nil)
}

使用 swift 3：

func showAlertBtnClicked(sender: UIButton) {
    let alert = UIAlertController(title: "This is title", message: "This is message", preferredStyle: .alert)
    self.present(alert, animated: true) {
        alert.view.superview?.isUserInteractionEnabled = true
        alert.view.superview?.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.alertControllerBackgroundTapped)))
    }
}

func alertControllerBackgroundTapped()
{
    self.dismiss(animated: true, completion: nil)
}

Answer 2

添加样式为

UIAlertActionStyleCancel

的单独取消操作。这样当用户点击外部时，您就会收到回调。

Obj-c

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Alert Title" message:@"A Message" preferredStyle:UIAlertControllerStyleActionSheet];
[alertController addAction:[UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action) {
 // Called when user taps outside
}]];

斯威夫特5.0

let alertController = UIAlertController(title: "Alert Title", message: "A Message", preferredStyle: .actionSheet)             
alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { 
    action in
         // Called when user taps outside
}))

Answer 3

斯威夫特，Xcode 9

使用取消按钮关闭 AlertController

向您的警报控制器提供操作，其中

UIAlertAction

的样式为

.cancel

let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
alertController.addAction(cancelAction)

使用此方法，当用户点击取消操作按钮以及警报控制器外部时，警报控制器将被关闭。

如果您不希望用户在alertController外部进行触摸后关闭alertController，请在当前方法完成关闭时禁用alertController第一个子视图的用户交互。

self.present(alertController, animated: true) {
     alertController.view.superview?.subviews[0].isUserInteractionEnabled = false
    }

在控制器视图之外的触摸时关闭 AlertController

如果您不想在控制器视图中使用取消按钮，并且希望在用户触摸控制器视图之外时关闭控制器，请这样做

self.present(alertController, animated: true) {
        let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.dismissAlertController))
        alertController.view.superview?.subviews[0].addGestureRecognizer(tapGesture)
}

@objc func dismissAlertController(){
    self.dismiss(animated: true, completion: nil)
}

Answer 4

如果您使用 Swift :

使用

addAction(_:)

和

style:UIAlertActionStyle.Cancel

添加操作。

当您点击按钮或在框架之外时，将调用`处理程序。

var alertVC = UIAlertController(...) // initialize your Alert View Controller

        alertVC.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler: {
            (alertAction: UIAlertAction!) in
            alertVC.dismissViewControllerAnimated(true, completion: nil)
        }))

Objective-C：

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:...];


[alertController addAction:[UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action) {
   [alertVC dismissViewControllerAnimated:YES completion:nil];
}]];

Answer 5

斯威夫特 4：

当用户点击使用 UIAlertController 创建的操作表之外时关闭操作表

代码片段：

// Declare Action Sheet reference
var actionSheet: UIAlertController!

// Init and Show Action Sheet
func showActionSheetClicked(sender: UIButton) {

    // Init Action Sheet
    actionSheet = UIAlertController(title: "Title", message: "Message", preferredStyle: .actionSheet)

    self.present(actionSheet, animated: true) {
        // Enabling Interaction for Transperent Full Screen Overlay
        self.actionSheet.view.superview?.subviews.first?.isUserInteractionEnabled = true

        // Adding Tap Gesture to Overlay
        self.actionSheet.view.superview?.subviews.first?.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.actionSheetBackgroundTapped)))
    }
}

// To dismiss Action Sheet on Tap
@objc func actionSheetBackgroundTapped() {
    self.actionSheet.dismiss(animated: true, completion: nil)
}

Answer 6

Obj-C 中最简单的方法：

UIAlertController *alert = [UIAlertController alertControllerWithTitle: ...
[self presentViewController:alert animated:YES completion:^{
                                       [alert.view.superview addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(alertControllerBackgroundTapped)]];
                                   }];

然后：

- (void)alertControllerBackgroundTapped
{
    [self dismissViewControllerAnimated: YES
                             completion: nil];
}

Answer 7

- (void)addBackgroundDismissTapForAlert:(UIAlertController *)alert {
    if (!alert.view.superview) {
        return;
    }
    alert.view.superview.userInteractionEnabled = YES;
    [alert.view.superview addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(alertControllerBackgroundTapped)]];
    for (UIView *subV in alert.view.superview.subviews) {
        if (subV.width && subV.height) {
            subV.userInteractionEnabled = YES;
            [subV addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(alertControllerBackgroundTapped)]];
        }
    }
}
- (void)alertControllerBackgroundTapped {

    [self dismissViewControllerAnimated: YES
                         completion: nil];
}

Answer 8

    UIView *alertView = self.alertController.view;
UIView *superPuperView = self.alertController.view.superview;
CGPoint tapCoord = [tap locationInView:superPuperView];
if (!CGRectContainsPoint(alertView.frame, tapCoord)) {
    //dismiss alert view
}

Answer 9

如果您查看调试警报的超级视图，您会发现它并不像向 _UIAlertControllerView 的 UITransitionView 添加点击手势识别器那么简单。您可以这样做

[presenter presentViewController:alertController animated:YES completion:^{
    NSArray <UIView *>* superviewSubviews = alertController.view.superview.subviews;
    for (UIView *subview in superviewSubviews) {
        if (CGRectEqualToRect(subview.bounds, weakSelf.view.bounds)) {
            [subview addSingleTapGestureWithTarget:weakSelf action:@selector(dismissModalTestViewController)];
        }
    }
}];

Answer 10

在 iOS 15 上，

UIAlertController

的视图层次结构似乎再次发生了变化。它呈现为包含控制器本身的新

UIWindow

。因此，为了在外面点击即可关闭：

present(alertController, animated: true) { [weak self] in
    guard let self = self else { return }

    let dismissGesture = UITapGestureRecognizer(target: self, action: #selector(self.shouldDismiss))

    self.alertController.view.window?.isUserInteractionEnabled = true
    self.alertController.view.window?.addGestureRecognizer(dismissGesture)
}

对于

shouldDismiss

功能：

@objc private func shouldDismiss() {
    alertController.dismiss(animated: true)
}

Answer 11

最简单的方法：

- (void)viewDidLoad {
    [super viewDidLoad];

    [self button];

}

- (void) button {
    UIButton * AlertButton = [UIButton buttonWithType:UIButtonTypeSystem];
    [AlertButton setTitle:@"Button" forState:UIControlStateNormal];
    AlertButton.frame = CGRectMake((self.view.frame.size.width/2) - 50 , (self.view.frame.size.height/2) - 25, 100, 50);
    [AlertButton addTarget:self action:@selector(Alert) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:AlertButton];
}

- (void)Alert {
    UIAlertController * alert = [UIAlertController alertControllerWithTitle:@"Alert Title" message:@"Alert Message" preferredStyle:UIAlertControllerStyleAlert];
    [self presentViewController: alert animated: YES completion:^{ alert.view.superview.userInteractionEnabled = YES; [alert.view.superview addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(DismissAlertByTab)]]; }];
}

- (void)DismissAlertByTab
{
    [self dismissViewControllerAnimated: YES completion: nil];
}

Answer 12

您应该将手势识别器添加到演示内容视图中。

let alertController = UIAlertController(title: "Title", message: "Message", preferredStyle: .alert)

present(alertController, animated: true, completion: {
    let backgroundTapDismissGesture = UITapGestureRecognizer(target: self, action: #selector(didTapDismissGesture(_:)))

    let transitionBGView = alertController.presentationController?.containerView?.subviews.first
    transitionBGView?.isUserInteractionEnabled = true
    transitionBGView?.addGestureRecognizer(backgroundTapDismissGesture)
})

...

@objc func didTapDismissGesture(_ sender: UITapGestureRecognizer) {
    alertController.dismiss(animated: true)
}