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说明：通知在页面传值中，通知是非常简单便捷的方式，具体过程是，发布者发布通知到通知中心，订阅者从发布中心获得最新通知，具体结构如下图
实现代码：
1，新建Single View Application工程，新建一个SecondViewController，用于作为发送端
2，在ViewController.m中添加UIButton用于跳转到SecondViewController，UILabel用于显示通知
@interface ViewController (){ UILabel *_label; } @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; //添加UIButton，用于跳转到SecondViewController UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(20, 200, 300, 44)]; [btn setTitle:@"ToSecondViewController" forState:UIControlStateNormal]; btn.backgroundColor = [UIColor grayColor]; [btn addTarget:self action:@selector(toSecondViewController) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:btn]; //添加UILabel，用于显示SecondViewController传过来的值 _label = [[UILabel alloc] initWithFrame:CGRectMake(20, 100, 300, 44)]; _label.backgroundColor = [UIColor yellowColor]; [self.view addSubview:_label]; } - (void)toSecondViewController { SecondViewController *second = [[SecondViewController alloc] init]; [self presentViewController:second animated:YES completion:nil]; }
3，在SecondViewController.m中添加UIButton，用于发送通知并且跳回ViewController，UILabel用于输入通知数据
@interface SecondViewController (){ UITextField *_textField; } @end @implementation SecondViewController - (void)viewDidLoad { [super viewDidLoad]; self.view.backgroundColor = [UIColor whiteColor]; //添加一个按钮用于返回ViewController UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(20, 200, 300, 44)]; [btn setTitle:@"BackToViewController" forState:UIControlStateNormal]; btn.backgroundColor = [UIColor blueColor]; [btn addTarget:self action:@selector(postNotification) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:btn]; //添加一个UITextField _textField = [[UITextField alloc] initWithFrame:CGRectMake(20, 100, 300, 44)]; _textField.backgroundColor = [UIColor greenColor]; [self.view addSubview:_textField]; }
4，在SecondViewController.m中实现发送通知方法
- (void)postNotification { NSDictionary *dict = [[NSDictionary alloc] initWithObjectsAndKeys:_textField.text,@"test" ,nil]; //创建通知 NSNotification *notification =[NSNotification notificationWithName:@"getValue" object:nil userInfo:dict]; //通过通知中心发送通知 [[NSNotificationCenter defaultCenter] postNotification:notification]; [self dismissViewControllerAnimated:YES completion:nil]; }
5，在ViewController.m中注册通知，并且实现注册通知方法
#import "ViewController.h" #import "SecondViewController.h" @interface ViewController (){ UILabel *_label; } @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; //添加UIButton，用于跳转到SecondViewController UIButton *btn = [[UIButton alloc] initWithFrame:CGRectMake(20, 200, 300, 44)]; [btn setTitle:@"ToSecondViewController" forState:UIControlStateNormal]; btn.backgroundColor = [UIColor grayColor]; [btn addTarget:self action:@selector(toSecondViewController) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:btn]; //添加UILabel，用于显示SecondViewController传过来的值 _label = [[UILabel alloc] initWithFrame:CGRectMake(20, 100, 300, 44)]; _label.backgroundColor = [UIColor yellowColor]; [self.view addSubview:_label]; //注册通知 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(getNotification:) name:@"getValue" object:nil]; } - (void)toSecondViewController { SecondViewController *second = [[SecondViewController alloc] init]; [self presentViewController:second animated:YES completion:nil]; } //实现注册通知方法，给label赋值 -(void)getNotification:(NSNotification*)notification{ NSDictionary *dict = [notification userInfo]; _label.text = [dict objectForKey:@"test"]; } @end
源码地址:https://github.com/rokistar/PassValueUsingNotification
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原文地址：http://www.cnblogs.com/Roki/p/4558820.html
