UIAlertController: addSubview

问题

I want to add a subview to my alertcontroller. But why do the buttons go on the top ? How do I fix the problem?

    let alert = UIAlertController(title: nil, message: nil, preferredStyle: UIAlertControllerStyle.alert)

    let somethingAction = UIAlertAction(title: "Something", style: .default, handler: {(alert: UIAlertAction!) in print("something")})

    let cancelAction = UIAlertAction(title: "Annuler", style: .cancel, handler: {(alert: UIAlertAction!) in print("cancel")})

    alert.addAction(somethingAction)
    alert.addAction(cancelAction)

    let customView = UIView()
    customView.backgroundColor = .green
    customView.translatesAutoresizingMaskIntoConstraints = false
    customView.widthAnchor.constraint(equalToConstant: 128).isActive = true
    customView.heightAnchor.constraint(equalToConstant: 128).isActive = true

    alert.view.addSubview(customView)

    customView.centerXAnchor.constraint(equalTo: alert.view.centerXAnchor).isActive = true
    customView.topAnchor.constraint(equalTo: alert.view.topAnchor).isActive = true
    customView.bottomAnchor.constraint(equalTo: alert.view.bottomAnchor, constant: -32).isActive = true
    self.present(alert, animated: true, completion:{})

回答1:

UIAlertController is a pretty closed system. Its designed to be the system standard alert. You should not be adding subviews to it.

I would create an custom UIViewController that can act as an alert. You can use the custom UIViewController transition to make appear the same way UIAlertController does.

There are also many GitHub projects that provide custom alert styles that you might like. Such as this one: https://github.com/DominikButz/DYAlertController

来源：https://stackoverflow.com/questions/43002236/uialertcontroller-addsubview