iPhone开发之窗口之间传递数据之Delegate

在IOS里两个UIView窗口之间传递参数方法有很多，比如

 1.使用SharedApplication,定义一个变量来传递.

 2.使用文件，或者NSUserdefault来传递

 3.通过一个单例的class来传递 

 4.通过Delegate来传递。 

这次主要学习如何使用通过Delegate的方法来在不同的UIView里传递数据 。

比如： 在窗口1中打开窗口2，然后在窗口2中填入一个数字，这个数字又回传给窗口1。 

窗口1

 

窗口2

 

窗口2的结果传递给窗口1 

 

工程截图：

窗口一：

//
//  ViewController.h
//  DelegateDemo
//
//  Created by Fox on 12-3-21.
//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import <UIKit/UIKit.h>


//定义一个协议用来传值
@protocol UIViewPassValueDelegate

- (void)passValue:(NSString *)value;

@end


//实现协议
@interface ViewController : UIViewController <UIViewPassValueDelegate>{

}
@property (retain, nonatomic) IBOutlet UITextField *texta;
- (IBAction)openPress:(id)sender;

@end

//
//  ViewController.m
//  DelegateDemo
//
//  Created by Fox on 12-3-21.
//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import "ViewController.h"
#import "ViewBController.h"

@implementation ViewController
@synthesize texta;


- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)viewDidUnload
{
    [self setTexta:nil];
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (IBAction)openPress:(id)sender {
    ViewBController *viewb = [[ViewBController alloc] initWithNibName:@"ViewBController" bundle:nil];
    viewb.delegate = self;
    [self setModalTransitionStyle:UIModalTransitionStyleCoverVertical];
    [self presentModalViewController:viewb animated:YES];
    
}
- (void)dealloc {
    [texta release];
    [super dealloc];
}

//实现协议的方法
#pragma mark UIViewPassValueDelegate mothod
- (void)passValue:(NSString *)value
{
    self.texta.text = value;
    NSLog(@"the get value is %@", value);
}

@end

窗口二：

//
//  ViewBController.h
//  DelegateDemo
//
//  Created by Fox on 12-3-21.
//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "ViewController.h"

@interface ViewBController : UIViewController{
    NSObject<UIViewPassValueDelegate> *delegate;//定义协议

}

@property (retain, nonatomic) IBOutlet UITextField *text;
@property (retain, nonatomic) NSObject<UIViewPassValueDelegate> *delegate;
- (IBAction)buttonpress:(id)sender;
@end

//
//  ViewBController.m
//  DelegateDemo
//
//  Created by Fox on 12-3-21.
//  Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import "ViewBController.h"

@implementation ViewBController
@synthesize text;
@synthesize delegate;

- (void)dealloc {
    [text release];
    [super dealloc];
}

- (IBAction)buttonpress:(id)sender {
    [delegate passValue:self.text.text];//调用协议的方法
    NSLog(@"self.value.text is%@", self.text.text);
    [self dismissModalViewControllerAnimated:YES]; 
}
@end

参考来自：http://www.cnblogs.com/likwo/archive/2011/03/02/1968785.html