IOS Delegate Agent (delegate) implements page pass value

Lvesli Original, reproduced please specify the original link thank you http://www.androiddev.net/lvesli_delegate/

A delegate is a behavior that gives an object an opportunity to react to a change in another object, or a corresponding other object. The basic idea is to solve the problem together.

In the program: in general

1. The tasks to be commissioned are:

1.1 Defining protocols and methods

1.2 Declaring a delegate variable

1.3 Setting up Proxies

1.4 Calling a delegate method from a delegate variable

2. The work that the agent needs to do is:

2.1 Following the agreement

2.2 Implementing a Delegate method

Here's a workaround for using delegates to implement page-pass values:

Join us There are two Viewcontroller, respectively: Viewcontroller and Trendviewcontroller

A. Requirements:

We want to implement a feature that jumps to Trendviewcontroller immediately when you click on a button on the Viewcontroller view and passes a string of strings past.

Two. Solution:

1. The most up-to-the-top declaration agreement in the ViewController.h file is as follows:

1	@protocolPassTrendValueDelegate

2	-(void)passTrendValues:(NSString*)values;//1.1定义协议与方法

3

@end

2. Continue declaring a delegate variable in ViewController.h

1	///1.定义向趋势页面传值的委托变量

2	@property(retain,nonatomic) id<PassTrendValueDelegate> trendDelegate;

3. Enter the VIEWCONTROLLER.M file in the Click Button Event function, set the proxy

1	#pragma mark 点击趋势按钮

2	-(void)trendBtnClick{

3	//create the view

4	TrendViewController *trendViewController = [[TrendViewController alloc] initWithNibName:@"TrendViewController"bundle:nil];

5

6	self.trendDelegate=trendViewController; //设置代理

7	[self.trendDelegate passTrendValues:@"Lves李兴乐"];

8

//页面跳转 省

9

}

4. Enter TrendViewController.h, refer to Viewcontroller's header file, and add the proxy protocol as follows:

1	#import "ViewController.h"

2

3	@interfaceTrendViewController : UIViewController<PassTrendValueDelegate>{

4

5

}

6

@end

5. Implement the Proxy function:

1	#pragma mark 实现传值协议方法

2	-(void)passTrendValues:(NSString*)values{

3	NSLog(@"values:::%@",values);

4

5

}

Run OK.

There are also ways to implement page pass values:

1. Notice

2. Methods

3. Proxy methods

4.SharedApplication

5.NSUserdefault

6. Pass through a single instance of class

IOS Delegate Agent (delegate) implements page pass value