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
Swift 3.0及更高版本更新
let actionSheetController: UIAlertController = UIAlertController(title: "SomeTitle", message: nil, preferredStyle: .actionSheet)
let editAction: UIAlertAction = UIAlertAction(title: "Edit Details", style: .default) { action -> Void in
print("Edit Details")
}
let deleteAction: UIAlertAction = UIAlertAction(title: "Delete Item", style: .default) { action -> Void in
print("Delete Item")
}
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .cancel) { action -> Void in }
actionSheetController.addAction(editAction)
actionSheetController.addAction(deleteAction)
actionSheetController.addAction(cancelAction)
// present(actionSheetController, animated: true, completion: nil) // doesn't work for iPad
actionSheetController.popoverPresentationController?.sourceView = yourSourceViewName // works for both iPhone & iPad
present(actionSheetController, animated: true) {
print("option menu presented")
}
其他回答
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 = []
}
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
}
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 = []
它将同时适用于iphone和ipad
func showImagePicker() {
var alertStyle = UIAlertController.Style.actionSheet
if (UIDevice.current.userInterfaceIdiom == .pad) {
alertStyle = UIAlertController.Style.alert
}
let alert = UIAlertController(title: "", message: "Upload Attachment", preferredStyle: alertStyle)
alert.addAction(UIAlertAction(title: "Choose from gallery", style: .default , handler:{ (UIAlertAction) in
self.pickPhoto(sourceType: .photoLibrary)
}))
alert.addAction(UIAlertAction(title: "Take Photo", style: .default, handler:{ (UIAlertAction) in
self.pickPhoto(sourceType: .camera)
}))
alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler:{ (UIAlertAction) in
}))
present(alert, animated: true, completion: nil)
}
斯威夫特5
我在iPhone上使用“actionsheet”样式，在iPad上使用“alert”样式。iPad显示在屏幕中央。不需要指定sourceView或将视图锚定在任何位置。
var alertStyle = UIAlertController.Style.actionSheet
if (UIDevice.current.userInterfaceIdiom == .pad) {
alertStyle = UIAlertController.Style.alert
}
let alertController = UIAlertController(title: "Your title", message: nil, preferredStyle: alertStyle)
编辑:根据ShareToD的建议，更新了已弃用的“UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.”垫“检查
