如何在UIAlertController外部点击时关闭UIAlertController？

Question

如何UIAlertController在外面敲击时解雇UIAlertController？

我可以添加一种UIAlertAction风格UIAlertActionStyleCancel来解雇UIAlertController.

但我想补充一点,当外界使用者开关功能UIAlertController的UIAlertController将开除.怎么做？谢谢.

Answer 1

使用样式添加单独的取消操作UIAlertActionStyleCancel.因此,当用户点击外部时,您将获得回调.

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
}]];

-

Answer 2

如果您要定位iOS> 9.3并使用Swift并且preferredStyle为Alert的设备,则可以使用以下代码段:

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)
}

随着迅捷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 3

Swift,Xcode 9

使用取消按钮关闭AlertController

提供行动的alertController那里UIAlertAction的风格.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alertController外部时,alertController将被解除.

如果您不希望用户在alertController外部触摸后解除alertController,请在当前方法的完成闭包中禁用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视图外部的touchup上关闭AlertController

如果您不想在控制器视图中使用取消按钮,并且想要在控制器视图外部进行用户修改时关闭控制器,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 4

如果您使用的是Swift:

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

当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 5

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)
}