在iPad上使用iOS 8正确呈现UIAlertController

在iOS 8.0中，苹果引入了UIAlertController来取代UIActionSheet。不幸的是，苹果没有提供任何关于如何展示的信息。我在hayaGeek的博客上找到了一个关于它的条目，然而，它似乎不能在iPad上运行。这种观点是完全错误的:

错误的:

正确的:

我使用以下代码在界面上显示它:

    let alert = UIAlertController()
    // setting buttons
    self.presentModalViewController(alert, animated: true)

是否有其他方法添加到iPad上?或者苹果只是忘记了iPad，或者还没有推出iPad ?

当前回答

斯威夫特5

适用于iPad和iPhone。

动作表下方悬停一个按钮

对于iPhone，动作表将显示正常，iPad将显示在按钮下方。

actionSheet.popoverPresentationController?.sourceView = fooButton
actionSheet.popoverPresentationController?.sourceRect = fooButton.bounds

动作表在屏幕/视图的中间

对于iPhone，动作表将正常显示，iPad将显示在屏幕/视图的中间。

actionSheet.popoverPresentationController?.sourceView = view
actionSheet.popoverPresentationController?.sourceRect = CGRect(x: view.bounds.midX, y: view.bounds.midY, width: 0, height: 0)
actionSheet.popoverPresentationController?.permittedArrowDirections = []

2022-03-07 00:44:00

其他回答

对我来说，我只需要添加以下内容:

if let popoverController = alertController.popoverPresentationController {
    popoverController.barButtonItem = navigationItem.rightBarButtonItem
}

2019-01-09 23:21:12

你可以通过使用UIPopoverPresentationController从弹窗中呈现一个UIAlertController。

在Obj-C:

UIViewController *self; // code assumes you're in a view controller
UIButton *button; // the button you want to show the popup sheet from

UIAlertController *alertController;
UIAlertAction *destroyAction;
UIAlertAction *otherAction;

alertController = [UIAlertController alertControllerWithTitle:nil
                                                      message:nil
                           preferredStyle:UIAlertControllerStyleActionSheet];
destroyAction = [UIAlertAction actionWithTitle:@"Remove All Data"
                                         style:UIAlertActionStyleDestructive
                                       handler:^(UIAlertAction *action) {
                                           // do destructive stuff here
                                       }];
otherAction = [UIAlertAction actionWithTitle:@"Blah"
                                       style:UIAlertActionStyleDefault
                                     handler:^(UIAlertAction *action) {
                                         // do something here
                                     }];
// note: you can control the order buttons are shown, unlike UIActionSheet
[alertController addAction:destroyAction];
[alertController addAction:otherAction];
[alertController setModalPresentationStyle:UIModalPresentationPopover];

UIPopoverPresentationController *popPresenter = [alertController 
                                              popoverPresentationController];
popPresenter.sourceView = button;
popPresenter.sourceRect = button.bounds;
[self presentViewController:alertController animated:YES completion:nil];

Swift 4.2的编辑，虽然有很多博客可用，但它可以节省你的时间去搜索他们。

if let popoverController = yourAlert.popoverPresentationController {
    popoverController.sourceView = self.view //to set the source of your alert
    popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0) // you can set this as per your requirement.
    popoverController.permittedArrowDirections = [] //to hide the arrow of any particular direction
}

2014-06-15 20:42:31

斯威夫特4.2 你可以像这样使用condition:

let alert = UIAlertController(title: nil, message: nil, preferredStyle: UIDevice.current.userInterfaceIdiom == .pad ? .alert : .actionSheet)

2020-09-28 13:18:17

只需添加以下代码在呈现您的动作表:

if let popoverController = optionMenu.popoverPresentationController {
    popoverController.sourceView = self.view
    popoverController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
    popoverController.permittedArrowDirections = []
}

2019-07-16 11:30:33