创建自定义对象继承NSObject类

Using different frameworks in my projects I have often faced with custom elements which created as class inherit from NSObject (correct me if something is wrong). What are the main rules of creating such UI elements?

在我的项目中使用不同的框架我经常遇到自定义元素,这些元素是从NSObject继承的类创建的(如果出现问题,请更正我)。创建此类UI元素的主要规则是什么?

3 个解决方案

#1

NSObject is the very basic class in Cocoa. It is responsible for the most basic things that every class needs, like memory management. (Almost) all classes in Cocoa inherit from NSObject and you usually subclass NSObject if you want to implement a model class.

NSObject是Cocoa中最基本的类。它负责每个类所需的最基本的东西,比如内存管理。 (几乎)Cocoa中的所有类都继承自NSObject,如果要实现模型类,通常会将NSObject子类化。

If you want to create your own GUI element, you should subclass UIView or UIControl. UIView will give you capabilities to do custom drawing, handling touch events and others. UIControl (which itself is a UIView subclass) adds functionality for control elements which the user can interact with, like UITextField, UISlider etc. This is what you should subclass if you plan to implement a custom control.

如果要创建自己的GUI元素,则应该为UIView或UIControl创建子类。 UIView将为您提供自定义绘图,处理触摸事件等功能。 UIControl(它本身是一个UIView子类)为用户可以与之交互的控件元素添加功能,如UITextField,UISlider等。如果您计划实现自定义控件,那么您应该将其子类化。

#2

Main purpose of using custom objects is to create model classes, which help in storing data which can be used through out the application.

使用自定义对象的主要目的是创建模型类,这有助于存储可以在整个应用程序中使用的数据。

For e.g. -

对于例如 -

@interface ServerResponse
.....
@property (nonatomic, retain) NSString *responseString;
@property (nonatomic, retain) NSArray *errorCodes;
.....
@end

In addition to this NSObject is root class in Objective C. Most classes inherit the feature of NSObject Classs.

除此之外,NSObject是Objective C中的根类。大多数类继承了NSObject类的特性。

#3

If you are creating UI elements you could inherit from NSObject, however I would strongly recommend to inherit from UIView or UIControl. Otherwise you will just be recreating functionality already given by UIControl.

如果您正在创建可以从NSObject继承的UI元素,但我强烈建议您继承UIView或UIControl。否则,您将只是重新创建UIControl已经提供的功能。

Additionally if you simply want to add additional functionality to a existing UI element, you could extend (create a category) to add that functionality.

此外,如果您只是想向现有UI元素添加其他功能,则可以扩展(创建类别)以添加该功能。

#1

#2