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 ?
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)
}
Swift 4及以上
我已经创建了一个扩展
extension UIViewController {
public func addActionSheetForiPad(actionSheet: UIAlertController) {
if let popoverPresentationController = actionSheet.popoverPresentationController {
popoverPresentationController.sourceView = self.view
popoverPresentationController.sourceRect = CGRect(x: self.view.bounds.midX, y: self.view.bounds.midY, width: 0, height: 0)
popoverPresentationController.permittedArrowDirections = []
}
}
}
使用方法:
let actionSheetVC = UIAlertController(title: "Title", message: nil, preferredStyle: .actionSheet)
addActionSheetForiPad(actionSheet: actionSheetVC)
present(actionSheetVC, animated: true, completion: nil)