在 UIAlertController 外部点击时如何关闭 UIAlertController？

Question

在UIAlertController之外点击时如何关闭UIAlertController？

我可以添加 UIAlertAction 样式 UIAlertActionStyleCancel 来关闭 UIAlertController。

但我想添加当用户在UIAlertController 之外点击时UIAlertController 将关闭的功能。怎么做？谢谢。

Answer 1

添加一个单独的取消操作，样式为UIAlertActionStyleCancel。这样当用户在外面点击时，你就会得到回调。

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
}]];

Swift 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 2

如果您使用的是 Swift：

使用addAction(_:) 和style:UIAlertActionStyle.Cancel 添加操作。

当您点击按钮或框架外时，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 3

如果您的目标设备是 iOS > 9.3 并且使用 Swift 并且首选样式为 Alert，您可以使用 sn-p，如下所示：

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 4

    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 5

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 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

如果您查看调试警报的超级视图，您会发现它不像向 _UIAlertControllerView 的 UITransitionView 添加轻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 8

- (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 9

斯威夫特，Xcode 9

使用取消按钮关闭 AlertController

为UIAlertAction 的样式为.cancel 的 alertController 提供操作

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

当用户点击取消操作按钮以及在 alertController 之外使用此方法时，alertController 将被关闭。

如果您不希望用户在alertController 之外进行修改后关闭alertController，请在当前方法的完成关闭中禁用alertController 的第一个子视图的用户交互。

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

在 Controller 视图之外的 touchup 上关闭 AlertController

如果您不希望控制器视图中的取消按钮，并且希望在用户在控制器视图之外进行触摸时关闭控制器，请执行此操作

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 10

斯威夫特 4：

当用户在使用 UIAlertController 创建的操作表之外点击时关闭操作表

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)
}