ios 中代理原理使用方法精讲

IOS中delegate的使用方法

写了一个简单的委托的试用测试：

首先创建FunctionTest类，声明委托：

FunctionTest.h

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//

// FunctionTest.h

// DelegateDemo

//

// Created by shx on 12-7-17.

// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.

//

#import <Foundation/Foundation.h>

@protocol FunctionTestDelegate;

@interface FunctionTest : NSObject

{

id<FunctionTestDelegate> delegate;

}

@property (nonatomic, assign)id<FunctionTestDelegate> delegate;

- (void)func1;

- (void)func2;

@end

@protocol FunctionTestDelegate <NSObject>

- (void)func3;

- (void)func4;

@end

FunctionTest.m

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//

// FunctionTest.m

// DelegateDemo

//

// Created by shx on 12-7-17.

// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.

//

#import "FunctionTest.h"

@implementation FunctionTest

@synthesize delegate;

- (void)func1

{

NSLog(@"function 1 called

");

[delegate performSelector:@selector(func3)];

}

- (void)func2

{

NSLog(@"function 2 called

");

[delegate performSelector:@selector(func4)];

}

@end

在appdelegate中实现委托：

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//

// AppDelegate.h

// DelegateDemo

//

// Created by shx on 12-7-17.

// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.

//

#import <UIKit/UIKit.h>

#import "FunctionTest.h"

@class ViewController;

@interface AppDelegate : UIResponder <UIApplicationDelegate,FunctionTestDelegate>

{

FunctionTest *test;

}

@property (strong, nonatomic) UIWindow *window;

@property (strong, nonatomic) ViewController *viewController;

@end

AppDelegate.m中实现：

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#pragma mark -FunctionTestDelegate

- (void)func3

{

NSLog(@"function 3 called

ns");

}

- (void)func4

{

NSLog(@"function 4 called

ns");

}

在

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

调用添加：

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test = [[FunctionTest alloc]init];

test.delegate = self;

[test func1];

[test func2];