如何快速覆盖 UIAlertController 中的便利初始化? [英] How can I override convenience init in UIAlertController for swift?

问题描述

我正在尝试覆盖 UIAlertController 中的便捷初始化，但它给了我一个错误，例如初始化程序不会覆盖其超类中的指定初始化程序".如何使用继承或扩展来覆盖它?我的代码如下.

I'm trying to override convenience init in UIAlertController, but it gives me an error like 'initializer does not override a designated initializer from its superclass'. How can I override it using inheritance or extension whatever? My codes are below.

import UIKit

class ColorAlertViewController: UIAlertController {

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()

    }

    override convenience init(title: String?, message: String?, preferredStyle: UIAlertControllerStyle, colorCode: String?){
        super.init(title: title, message: message, preferredStyle: preferredStyle)
    }
}

推荐答案

你没有覆盖任何便利的 init，看起来你正在创建一个新的.

you are not overriding any convenience init, it looks like you are creating a new one.

convenience init(title: String?, message: String?, preferredStyle: UIAlertControllerStyle, colorCode: String?){
    self.init(title: title, message: message, preferredStyle: preferredStyle)
}

可能就是你想要的，你只需要处理颜色代码

Is probably what you want, you just need to handle the color code

看来您将不得不绕道而行:

Looks like you are going to have to go a round about way:

首先创建一个创建扩展

extension UIAlertController
{

    class func create(title: String?, message: String?, preferredStyle: UIAlertControllerStyle) -> AnyObject
    {
        return UIAlertController(title: title, message: message, preferredStyle: preferredStyle);
    }
}

然后在 ColorAlertViewController 中，您将创建另一个函数来创建此对象:

Then in the ColorAlertViewController, you will create another function to create this object:

class func createWithColor(title: String?, message: String?, preferredStyle: UIAlertControllerStyle, colorCode: String?) -> AnyObject
{
    var c = super.create(title, message: message, preferredStyle: preferredStyle);
    //handle color code here
    return c;
}

现在你想在任何地方创建这个对象，只要调用

Now anywhere you want to create this object, just call

var colorAlertView = ColorAlertViewController.createWithColor("title Name", message: "the message", preferredStyle: .ActionSheet, colorCode: "the color");

当然这在 UI 构建器中不起作用，您必须通过代码创建它.

of course this won't work inside the UI builder, you would have to create this via code.

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