如何在Objective-C中声明事件和委托? [英] How to declare events and delegates in Objective-C?

问题描述

C#代码:

public delegate void ItemFound(ChunkDetails ObjChunkDetails);
public event ItemFound eventItemFound;

如何在Objective-C中声明上述事件委托机制?

How to declare the above event delegates mechanism in Objective-C?

我试图在Objective-c中声明委托方法，但仍然需要帮助.

I tried to declare delegates method in objective-c but still i need help.

Objective-C:

Objective-C:

+ (void) ItemFound:(ChunkDetails *)ObjItemDetails;

那么，如何在Objective-C的.h文件中声明事件和委托的签名?

So how to declare signature of events and delegates in .h file of Objective-C?

推荐答案

在示例A中，类A调用类B来执行操作，然后返回某些操作，我们将执行以下操作:

In the example where class A calls class B to perform an action and then return something we would do this:

B类的.h，它高于@interface

Class B's .h, this goes above the @interface

@protocol CLASSBNAMEDelegate <NSObject>

- (void) YOURMETHOD:(id) returnValue

@end

然后在@interface下，我们添加一个委托属性:

Then under the @interface we add a delegate property:

@property (nonatomic, weak) id < CLASSBNAMEDelegate > delegate;

在b.m类中，您要将消息发送回A类，您将:

In class b .m where you want to send a message back to Class A you would:

 if ([self.delegate respondsToSelector:@selector(YOURMETHOD:)]) {
    [self.delegate YOURMETHOD:value];
}

在使用B类的A类中，请确保像这样设置委托:

In Class A, where you use Class B be sure to set the delegate like so:

ClassB *b = [Class B etc....];
[b setDelegate:self];

在A类标题中，请确保您:

IN Class A Header make sure you:

@interface CLASSA : NSObject <CLASSBNAMEDelegate>

然后您需要响应选择器:

Then you would need to respond to the selector:

- (void) YOURMETHOD:(id) value{}

希望这对您有帮助...

Hope this helps...

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