我一直在努力创建一个UIAlertView在Swift，但由于某种原因，我不能得到正确的声明，因为我得到这个错误:
无法找到一个超载的'init'接受提供的 参数
我是这样写的:
let button2Alert: UIAlertView = UIAlertView(title: "Title", message: "message",
delegate: self, cancelButtonTitle: "OK", otherButtonTitles: nil)
然后我使用:
button2Alert.show()
到目前为止，它正在崩溃，我只是不能得到正确的语法。
当前回答
@IBAction func Alert(sender: UIButton) {
var alertView:UIAlertView = UIAlertView()
alertView.title = "Alert!"
alertView.message = "Message"
alertView.delegate = self
alertView.addButtonWithTitle("OK")
alertView.show()
}
试试这个
其他回答
@IBAction func Alert(sender: UIButton) {
var alertView:UIAlertView = UIAlertView()
alertView.title = "Alert!"
alertView.message = "Message"
alertView.delegate = self
alertView.addButtonWithTitle("OK")
alertView.show()
}
试试这个
SWIFT 4:简单地为UIViewController创建一个扩展，如下所示:
extension UIViewController {
func showSuccessAlert(withTitle title: String, andMessage message:String) {
let alert = UIAlertController(title: title, message: message,
preferredStyle: UIAlertController.Style.alert)
alert.addAction(UIAlertAction(title: "OK".localized, style:
UIAlertAction.Style.default, handler: nil))
self.present(alert, animated: true, completion: nil)
}
}
现在在你的ViewController中，直接调用上面的函数，就好像它们是由UIViewController提供的一样。
yourViewController.showSuccessAlert(withTitle:
"YourTitle", andMessage: "YourCustomTitle")
从UIAlertView类:
// UIAlertView已弃用。使用UIAlertController 将UIAlertControllerStyleAlert改为preferredStyle
在iOS 8上，你可以这样做:
let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)
UIAlertController是一个单独的类，用于创建和交互我们在ios8中知道的UIAlertViews和UIActionSheets。
编辑:处理动作:
alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { action in
switch action.style{
case .Default:
print("default")
case .Cancel:
print("cancel")
case .Destructive:
print("destructive")
}
}}))
为Swift 3编辑:
let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.default, handler: nil))
self.present(alert, animated: true, completion: nil)
为Swift 4.x编辑:
let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: { action in
switch action.style{
case .default:
print("default")
case .cancel:
print("cancel")
case .destructive:
print("destructive")
}
}))
self.present(alert, animated: true, completion: nil)
// UIAlertView的自定义类
//MARK:- MODULES
import Foundation
import UIKit
//MARK:- CLASS
class Alert : NSObject{
static let shared = Alert()
var okAction : AlertSuccess?
typealias AlertSuccess = (()->())?
var alert: UIAlertController?
/** show */
public func show(title : String?, message : String?, viewController : UIViewController?, okAction : AlertSuccess = nil) {
let version : NSString = UIDevice.current.systemVersion as NSString
if version.doubleValue >= 8 {
alert = UIAlertController(title: title, message: message, preferredStyle:.alert)
alert?.addAction(UIAlertAction(title: "OK", style: .default, handler: { (action: UIAlertAction) in
if let okAction = okAction {
okAction()
}
}))
viewController?.present(alert ?? UIAlertController(), animated:true, completion:nil);
}
}
/** showWithCancelAndOk */
public func showWithCancelAndOk(title : String, okTitle : String, cancelTitle : String, message : String, viewController : UIViewController?, okAction : AlertSuccess = nil, cancelAction : AlertSuccess = nil) {
let version:NSString = UIDevice.current.systemVersion as NSString;
if version.doubleValue >= 8 {
alert = UIAlertController(title: title, message: message, preferredStyle:.alert)
alert?.addAction(UIAlertAction(title: cancelTitle, style: .default, handler: { (action: UIAlertAction) in
if let cancelAction = cancelAction {
cancelAction()
}
}))
alert?.addAction(UIAlertAction(title: okTitle, style: .default, handler: { (action: UIAlertAction) in
if let okAction = okAction {
okAction()
}
}))
viewController?.present(alert!, animated:true, completion:nil);
}
}
/** showWithTimer */
public func showWithTimer(message : String?, viewController : UIViewController?) {
let version : NSString = UIDevice.current.systemVersion as NSString
if version.doubleValue >= 8 {
alert = UIAlertController(title: "", message: message, preferredStyle:.alert)
viewController?.present(alert ?? UIAlertController(), animated:true, completion:nil)
let when = DispatchTime.now() + 1
DispatchQueue.main.asyncAfter(deadline: when){
self.alert?.dismiss(animated: true, completion: nil)
}
}
}
}
使用:
Alert.shared.show(title: "No Internet Connection", message: "The internet connection appers to be offline.", viewController: self) //without ok action
Alert.shared.show(title: "No Internet Connection", message: "The internet connection appers to be offline.", viewController: self, okAction: {
//ok action
}) // with ok action
Alert.shared.show(title: "No Internet Connection", message: "The internet connection appers to be offline.", viewController: self, okAction: {
//ok action
}, cancelAction: {
//cancel action
}) //with cancel and ok action
Alert.shared.showWithTimer(message : "This is an alert with timer", viewController : self) //with timer
下面是Swift中AlertView的一个非常简单的函数:
class func globalAlertYesNo(msg: String) {
let alertView = UNAlertView(title: "Title", message: msg)
alertView.messageAlignment = NSTextAlignment.Center
alertView.buttonAlignment = UNButtonAlignment.Horizontal
alertView.addButton("Yes", action: {
print("Yes action")
})
alertView.addButton("No", action: {
print("No action")
})
alertView.show()
}
在使用此函数时，必须将message作为字符串传递。
