子类化后委托？ [英] Delegate after subclassing?

问题描述

对不起，我无法为标题制定一个简短的问题..

如果我是一个类的子类使用委托协议和属性，我的委托仍然需要实现超类的委托协议，还是我必须为子类定义一个新的委托协议？

In case i subclass a class with a delegate protocol and property, does my delegate still need to implement the delegate protocol of the superclass, or do i have to define a new one for the subclass?

在我的情况下，我的子类 UIImagePickerController ：

In my case I subclassed UIImagePickerController:

[(UIImagePickerController *)self.myUIImagePickerControllerSubclassInstance setDelegate:self];

当我尝试将其委​​托设置为 self ，从某些视图控制器我收到以下警告：

When I try to set its delegate to self, from some view controller I get the following warning:

警告：语义问题：将'ViewController *'发送到$ b $的参数b不兼容类型
'id'

warning: Semantic Issue: Sending 'ViewController *' to parameter of incompatible type 'id'

推荐答案

您的代表需要遵守 UIImagePickerController 属性声明：

Your delegate needs to comply with UIImagePickerController property declaration:

@property（非原子，赋值）id< UINavigationControllerDelegate，UIImagePickerControllerDelegate>委托

因此，尝试将< UIImagePickerControllerDelegate> 添加到您的子类接口：

So, try adding <UIImagePickerControllerDelegate> to your subclass interface:

@interface YourPicker : UIImagePickerController <UIImagePickerControllerDelegate>
...
@end

可能你需要 UINavigationControllerDelegate 并实施强制方法（如果有的话）。

And probably you'll need UINavigationControllerDelegate and implement mandatory methods, if any.

这篇关于子类化后委托？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！