通知模式实现两个textField传值及模态视图——iOS开发

利用通知模式，实现两个不同界面的textField之间的传值，在界面二输入字符，传值到前一界面的textField。

界面的切换，这里临时先用模态视图实现。（重点在传值。所以没纠结设计界面排版。丑了点大家见谅）

大家不要看代码看上去好像挺多。由于我没使用storyboard/xib，是代码实现布局，所以通知和模态视图切换的代码非常少~

实现效果：

点击下一页按钮，进入界面二：

在textField处输入字符串：

点击返回按钮，回到界面一。此时界面一的textField处也有字符串

代码部分：

AppDelegate.m

#import "AppDelegate.h"
#import "ViewController1.h"@interface AppDelegate ()@end@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];self.window.backgroundColor = [UIColor whiteColor];[self.window makeKeyAndVisible];ViewController1 *vc1 = [[ViewController1 alloc] init];self.window.rootViewController = vc1;return YES;
}

ViewController1.m

#import "ViewController1.h"
#import "ViewController2.h"@interface ViewController1 ()
{UITextField *text1;
}
@end@implementation ViewController1- (void)viewDidLoad {[super viewDidLoad];self.view.backgroundColor = [UIColor greenColor];UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 100, 50)];label.text = @"界面一";[self.view addSubview:label];text1 = [[UITextField alloc] initWithFrame:CGRectMake(50, 150, 100, 50)];text1.backgroundColor = [UIColor whiteColor];[self.view addSubview:text1];UIButton *button1 = [[UIButton alloc] initWithFrame:CGRectMake(50, 250, 100, 50)];[button1 addTarget:self action:@selector(pushButtonAction:) forControlEvents:UIControlEventTouchUpInside];[button1 setTitle:@"下一页" forState:UIControlStateNormal];button1.backgroundColor = [UIColor blackColor];[self.view addSubview:button1];//    注冊观察者[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(returnAction:) name:@"chuanzhi" object:nil];// Do any additional setup after loading the view.
}- (void)returnAction:(NSNotification *)text {text1.text = text.userInfo[@"returnInfo"];
}- (void)pushButtonAction:(UIButton *)btn {ViewController2 *vc2 = [[ViewController2 alloc] init];vc2.modalPresentationStyle = UIModalPresentationFullScreen;  //切换效果[self presentViewController:vc2 animated:YES completion:nil];
}

ViewController2.m

#import "ViewController2.h"@interface ViewController2 ()
{UITextField *text2;
}
@end@implementation ViewController2- (void)viewDidLoad {[super viewDidLoad];self.view.backgroundColor = [UIColor blueColor];UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 100, 50)];label.text = @"界面二";[self.view addSubview:label];text2 = [[UITextField alloc] initWithFrame:CGRectMake(50, 150, 100, 50)];text2.backgroundColor = [UIColor whiteColor];[self.view addSubview:text2];UIButton *button2 = [[UIButton alloc] initWithFrame:CGRectMake(50, 250, 100, 50)];[button2 addTarget:self action:@selector(returnButtonAction:) forControlEvents:UIControlEventTouchUpInside];[button2 setTitle:@"返回" forState:UIControlStateNormal];button2.backgroundColor = [UIColor blackColor];[self.view addSubview:button2];// Do any additional setup after loading the view.
}- (void)returnButtonAction:(UIButton *)btn {NSDictionary *dic = @{@"returnInfo" : self->text2.text};NSNotification *notification = [NSNotification notificationWithName:@"chuangzhi" object:nil userInfo:dic];[[NSNotificationCenter defaultCenter] postNotification:notification];[self dismissViewControllerAnimated:NO completion:nil];
}