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
// 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
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
如果你的目标是iOS 7和8，你需要这样的东西来确保你对每个版本都使用了正确的方法，因为UIAlertView在iOS 8中已弃用，但UIAlertController在iOS 7中不可用:
func alert(title: String, message: String) {
if let getModernAlert: AnyClass = NSClassFromString("UIAlertController") { // iOS 8
let myAlert: UIAlertController = UIAlertController(title: title, message: message, preferredStyle: .Alert)
myAlert.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
self.presentViewController(myAlert, animated: true, completion: nil)
} else { // iOS 7
let alert: UIAlertView = UIAlertView()
alert.delegate = self
alert.title = title
alert.message = message
alert.addButtonWithTitle("OK")
alert.show()
}
}
下面是警报视图和动作表的可重用代码，只需写一行在应用程序的任何地方显示警报
class AlertView{
static func show(title:String? = nil,message:String?,preferredStyle: UIAlertControllerStyle = .alert,buttons:[String] = ["Ok"],completionHandler:@escaping (String)->Void){
let alert = UIAlertController(title: title, message: message, preferredStyle: preferredStyle)
for button in buttons{
var style = UIAlertActionStyle.default
let buttonText = button.lowercased().replacingOccurrences(of: " ", with: "")
if buttonText == "cancel"{
style = .cancel
}
let action = UIAlertAction(title: button, style: style) { (_) in
completionHandler(button)
}
alert.addAction(action)
}
DispatchQueue.main.async {
if let app = UIApplication.shared.delegate as? AppDelegate, let rootViewController = app.window?.rootViewController {
rootViewController.present(alert, animated: true, completion: nil)
}
}
}
}
用法:
class ViewController: UIViewController {
override func viewWillAppear(_ animated: Bool) {
AlertView.show(title: "Alert", message: "Are you sure ?", preferredStyle: .alert, buttons: ["Yes","No"]) { (button) in
print(button)
}
}
}
class Preview: UIViewController , UIAlertViewDelegate
{
@IBAction func MoreBtnClicked(sender: AnyObject)
{
var moreAlert=UIAlertView(title: "Photo", message: "", delegate: self, cancelButtonTitle: "No Thanks!", otherButtonTitles: "Save Image", "Email", "Facebook", "Whatsapp" )
moreAlert.show()
moreAlert.tag=111;
}
func alertView(alertView: UIAlertView, didDismissWithButtonIndex buttonIndex: Int)
{
if alertView.tag==111
{
if buttonIndex==0
{
println("No Thanks!")
}
else if buttonIndex==1
{
println("Save Image")
}
else if buttonIndex == 2
{
println("Email")
}
else if buttonIndex == 3
{
println("Facebook")
}
else if buttonIndex == 4
{
println("Whatsapp")
}
}
}
}
点击查看
@IBAction func testClick(sender: UIButton) {
var uiAlert = UIAlertController(title: "Title", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
self.presentViewController(uiAlert, animated: true, completion: nil)
uiAlert.addAction(UIAlertAction(title: "Ok", style: .Default, handler: { action in
println("Click of default button")
}))
uiAlert.addAction(UIAlertAction(title: "Cancel", style: .Cancel, handler: { action in
println("Click of cancel button")
}))
}
完成两个按钮确定&取消
