一、自定义方法
func showAlertWithActionHandler(title: String?, message: String?, preferredStyle: UIAlertControllerStyle = .alert, defaultHandler: (() ->Void)? = nil, cancelHandler: (() -> Void)? = nil)
{
let alert = UIAlertController(title: title, message: message, preferredStyle: preferredStyle)
let defaultAction = UIAlertAction(title: "好的", style: .default) { (alert) in
defaultHandler!()
}
alert.addAction(defaultAction)
if cancelHandler != nil
{
let cancelAction = UIAlertAction(title: "取消"), style: .cancel) { (alert) in
cancelHandler!()
}
alert.addAction(cancelAction)
}
// 获取当前显示的 ViewController
let theViewControllerYouSee = UIViewController.currentViewController()
theViewControllerYouSee?.present(alert, animated: true, completion: nil)
}
二、 获取当前显示的 ViewController
extension UIViewController
{
// 获取当前显示的 ViewController
class func currentViewController(base: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController?
{
if let nav = base as? UINavigationController
{
return currentViewController(base: nav.visibleViewController)
}
if let tab = base as? UITabBarController
{
return currentViewController(base: tab.selectedViewController)
}
if let presented = base?.presentedViewController
{
return currentViewController(base: presented)
}
return base
}
}
