ios - 如何使用委托(delegate)从一个 Controller 向另一个 Controller 发送消息？

Question

我的一个 Controller 中有一个 UDPSocket，我知道我必须使用委托(delegate)。我必须添加哪些功能才能使其从另一个 Controller 访问我的 udpsocket？

使用像这样的东西会很棒

[controller1.udpsocket sendData:data toHost:host] 

但我知道它不好，该怎么办呢？

Answer 1

#import <Foundation/Foundation.h>

@protocol DownLoadImageDelegate<NSObject>
@required
-(void)ImageDownLoaded:(UIImage*)image;

@end


@interface DownLoadImage : NSObject 
{

    id<DownLoadImageDelegate> mDelegate;
    NSURLConnection *mConnection;
    NSMutableData *mData;
}

@property(nonatomic,retain) id<DownLoadImageDelegate> delegate;
@end

//InViewController class 

DownLoadImage *imageDownLoad = [[DownLoadImage alloc]init];
imageDownLoad.delegate=self;
//and implement the delegate method declared in DownLoadImage class in ViewController class as

-(void)ImageDownLoaded:(UIImage *)image
{
    NSLog(@"Image%@",image);
    [mImageView setImage:image];
}