swift - 无法为 UIImagePickerController 创建便利的初始值设定项

Question

我正在尝试为 UIImagePickerController 创建一个方便的初始值设定项，但遇到以下错误:

extension UIImagePickerController {
    convenience init(sourceType: UIImagePickerControllerSourceType, delegate: UIImagePickerControllerDelegate?) {
        self.init()
        self.sourceType = sourceType
        self.delegate = delegate
    }
}

错误消息

Cannot assign a value of type 'UIImagePickerControllerDelegate?' to a value of type 'protocol <UIImagePickerControllerDelegate, UINavigationControllerDelegate>?'

Answer 1

环顾四周后，我想到了以下内容，但这似乎有点麻烦。

extension UIImagePickerController {
    convenience init<T: UIImagePickerControllerDelegate where T: UINavigationControllerDelegate>(sourceType: UIImagePickerControllerSourceType, delegate: T?) {
        self.init()
        self.sourceType = sourceType
        self.delegate = delegate
    }
}