iOS 页面跳转传值，属性传值，代理传值，代码块传值，单例传值，通知传值

有时候我们在页面跳转的时候回传递相应的参数，如，你想把在第一个页面的文本框里的内容显示在第二个文本框中，或者你又想把第二个文本框中的内容改变之后到第一个页面的文本框中，所有，这个时候我们就要用到页面跳转传值

1.属性传值（正向传值）

属性传值是正向传值，只可以从前面一个页面传递到第二个页面，不可以从第二个页面传递到第一个页面

2.代理传值（逆向传值）

代理传值是逆向传值

代理传值步骤

代理传值
适用于反向传值
1.1 创建协议及协议方法在反向传值的页面（SecondViewController）中
1.2 创建协议类型的属性在SecondViewController中创建属性id<postValueDelegate> delegate
1.3 调用属性即delegate
在SecondViewController页面中对象传值的方法中调用
[self.delegate postValue:self.textName.text];

1.4 在第一页即显示修改过信息的页面
遵循协议实现协议方法指定代理对象（即在页面传值参数的方法中为代理赋值）

具体代码如下

firstViewController.h

#import <UIKit/UIKit.h>
#import "secondViewController.h"
@interface firstViewController : UIViewController<postValueDeletage,UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@end

firstViewController.m

#import "firstViewController.h"

@interface firstViewController ()

@end

@implementation firstViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor colorWithRed:0.565 green:1.000 blue:0.994 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.delegate=self;
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    [self.view addSubview:self.name1];
    
    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"点击" forState:0];
    [self.btn addTarget:self action:@selector(next) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];
    
    
}

-(void)postValue:(NSString *)str{

    self.name1.text=str;
}

-(void)next{
    secondViewController *second=[[secondViewController alloc]init];
    second.deletage=self;
    second.str=self.name1.text;
    [self presentViewController:second animated:YES completion:nil];
    
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField{

    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    
    return YES;
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    [self.name1 resignFirstResponder];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

secondViewController.h 第二个页面

#import <UIKit/UIKit.h>
@protocol postValueDeletage <NSObject>

-(void)postValue:(NSString *)str;

@end
@interface secondViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@property(nonatomic,strong)NSString *str;
@property(nonatomic,assign)id<postValueDeletage> deletage;
@end

secondViewController.m

#import "secondViewController.h"

@interface secondViewController ()

@end

@implementation secondViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor colorWithRed:1.000 green:0.314 blue:0.659 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    self.name1.text=self.str;
    [self.view addSubview:self.name1];
    self.name1.delegate=self;
    self.name1.text=self.str;
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"上一页" forState:0];
    [self.btn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];

}
-(void)back{
    
    [self.deletage postValue:self.name1.text];
    [self dismissViewControllerAnimated:YES completion:nil];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


-(BOOL)textFieldShouldReturn:(UITextField *)textField{

    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    [self.name1 resignFirstResponder];
    
}

AppDelegate.h

#import <UIKit/UIKit.h>
#import "firstViewController.h"
@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;


@end

AppDelegate.m文件

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    firstViewController *first=[[firstViewController alloc]init];
    self.window.rootViewController=first;
    
    
    return YES;
}

3.单例传值（双向传值）

首先创建一个单例类

AppStatus.h

#import <Foundation/Foundation.h>

@interface AppStatus : NSObject<NSCopying>
@property(nonatomic,copy)NSString *contextStr;
+(AppStatus *)shareInstance;
@end

AppStatus.m文件

#import "AppStatus.h"

@implementation AppStatus
static AppStatus *appstatus;
//单例方法
+(AppStatus *)shareInstance{
    if (appstatus==nil) {
        appstatus=[[AppStatus alloc]init];
    }
    
    
    return appstatus;
}
//单例方法 初始化
+(instancetype)allocWithZone:(struct _NSZone *)zone{
    if (appstatus==nil) {
        appstatus=[super allocWithZone:zone];
    }
    return appstatus;
}

//单例方法 复制
-(id)copyWithZone:(NSZone *)zone{

    return self;
}
@end

第一个页面

firstViewController.h

#import <UIKit/UIKit.h>
#import "sceondViewController.h"
#import "AppStatus.h"
@interface firstViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@end

firstViewController.m

#import "firstViewController.h"

@interface firstViewController ()

@end

@implementation firstViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor colorWithRed:0.565 green:1.000 blue:0.994 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    self.name1.delegate=self;
    [self.view addSubview:self.name1];
    
    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"下一页" forState:0];
    [self.btn addTarget:self action:@selector(next) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];

}

//这个方法是执行多遍的  相当于刷新view

-(void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
      //把contextStr赋值到first中文本框的内容中
    self.name1.text=[AppStatus shareInstance].contextStr;
}
-(void)next{

    sceondViewController *second=[[sceondViewController alloc]init];
    //把first中文本框的内容赋值到contextStr中
    [AppStatus shareInstance].contextStr=self.name1.text;
    NSLog(@"%@",[AppStatus shareInstance].contextStr);
    
    [self presentViewController:second animated:YES completion:nil];
    
    
    
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    [self.name1 resignFirstResponder];
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField{

    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

第二个页面sceondViewController.h

#import <UIKit/UIKit.h>
#import "AppStatus.h"
@interface sceondViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@end

#import "sceondViewController.h"

@interface sceondViewController ()

@end

@implementation sceondViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor colorWithRed:1.000 green:0.416 blue:0.612 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    self.name1.text=[AppStatus shareInstance].contextStr;
    self.name1.delegate=self;
    [self.view addSubview:self.name1];

    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"上一页" forState:0];
    [self.btn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];
    
}
-(void)back{
    
    //把second中的文本框的值赋值给单例类的contextStr
    [AppStatus shareInstance].contextStr=self.name1.text;
    NSLog(@"%@",[AppStatus shareInstance].contextStr);

    [self dismissViewControllerAnimated:YES completion:nil];
    
    
    
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField{
    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    [self.name1 resignFirstResponder];
}

//这个方法是执行多遍的  相当于刷新view
-(void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    //把contextStr赋值到second中文本框的内容中
    self.name1.text=[AppStatus shareInstance].contextStr;
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

把根视图转到第一个视图，最后代码和代理模式的一样，在AppDelegate的

4.通知传值（逆向传值）

注意：通知传值是逆向传值，只能在第二个页面创建通知和发送通知，在第一个页面接收通知，并读取通知里的信息

第一个页面

firstViewController.h

#import <UIKit/UIKit.h>
#import "secondViewController.h"
@interface firstViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;

@end

firstViewController.m

#import "firstViewController.h"

@interface firstViewController ()

@end

@implementation firstViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor colorWithRed:0.565 green:1.000 blue:0.994 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    self.name1.delegate=self;
    [self.view addSubview:self.name1];
    
    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"点击" forState:0];
    [self.btn addTarget:self action:@selector(next) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];
    
    //添加通知
    
    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(ChangeNameNotification:) name:@"order" object:nil];
    
    
}
//通知方法
-(void)ChangeNameNotification:(NSNotification *)notification{
    
    NSDictionary *nameDic=notification.userInfo;
    NSLog(@"%@",nameDic);
    self.name1.text=[nameDic objectForKey:@"key"];
    
    
}
-(void)next{
 
    secondViewController *second=[[secondViewController alloc]init];
    second.str=self.name1.text;
    [self presentViewController:second animated:YES completion:nil];
    

    
}
//移除通知
-(void)dealloc{
    [[NSNotificationCenter defaultCenter]removeObserver:self name:@"order" object:nil];
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField{
    if ([textField  isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    [self.name1 resignFirstResponder];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

第二个页面secondViewController.h

#import <UIKit/UIKit.h>

@interface secondViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@property(nonatomic,strong)NSString *str;
@end

第二个页面secondViewController.m

#import "secondViewController.h"

@interface secondViewController ()

@end

@implementation secondViewController



- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor=[UIColor colorWithRed:1.000 green:0.314 blue:0.659 alpha:1.000];
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 200, 50)];
    self.name1.backgroundColor=[UIColor colorWithRed:0.905 green:0.903 blue:0.910 alpha:1.000];
    [self.view addSubview:self.name1];
    
    self.name1.text=self.str;
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(150, 200, 100, 100)];
    [self.btn setTitle:@"上一页" forState:0];
    [self.btn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
    self.btn.backgroundColor=[UIColor colorWithRed:0.210 green:0.257 blue:0.382 alpha:1.000];
    
    
    [self.view addSubview:self.btn];

}
-(void)back{
    //创建通知
    NSNotification *no=[[NSNotification alloc]initWithName:@"order" object:self userInfo:@{@"key":self.name1.text}];
    //通知中心发送通知
    [[NSNotificationCenter defaultCenter] postNotification:no];
    [self dismissViewControllerAnimated:YES completion:nil];
    
    
    
}

-(BOOL)textFieldShouldReturn:(UITextField *)textField{
    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    
    [self.name1 resignFirstResponder];

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*

把根视图转到第一个视图，最后代码和代理模式的一样，在AppDelegate的

5.代码块传值（逆向传值）

代码块传值步骤

/**

* 代码块传值从后往前传值

1.声明代码块（secondXXX.h）

2.声明一个代码块的类型属性（secondXXX.h）

3.调用代码块（secondXXX.m）

4.实现代码块(FirstXXX.m)

第一个页面firstViewController.h和

#import <UIKit/UIKit.h>
#import "secondViewController.h"
@interface firstViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;

@end

#import "firstViewController.h"

@interface firstViewController ()

@end

@implementation firstViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor=[UIColor redColor];
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
    self.name1.borderStyle=2;
    self.name1.delegate=self;
    [self.view addSubview:self.name1];
    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
    [self.btn setTitle:@"下一页" forState:0];
    [self.btn addTarget:self action:@selector(next) forControlEvents:UIControlEventTouchUpInside];
    
    [self.view addSubview:self.btn];
}

//-(void)postValue:(NSString *)str{
//
//    self.name1.text=str;
//}

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField{

    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    
    return YES;
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    [self.name1 resignFirstResponder];
}
-(void)next{
    secondViewController *second=[[secondViewController alloc]init];
    second.str=self.name1.text;
    
    second.myBlock=^(NSString *info){
    
        self.name1.text=info;
    
    };
//    second.deletage=self;
    [self presentViewController:second animated:YES completion:nil];

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

第二个页面 firstViewController.h和firstViewController.m

#import <UIKit/UIKit.h>
typedef void(^postValueBlock)(NSString *info);
//@protocol postValueDeletage <NSObject>
//
//-(void)postValue:(NSString *)str;
//
//@end

/**
 *  代码块传值 从后往前传值
 1.声明代码块（secondXXX.h）
 2.声明一个代码块的类型属性（secondXXX.h）
 3.调用代码块（secondXXX.m）
 4.实现代码块(FirstXXX.m)
 
 */

@interface secondViewController : UIViewController<UITextFieldDelegate>
@property(nonatomic,strong)UITextField *name1;
@property(nonatomic,strong)UIButton *btn;
@property(nonatomic,copy)NSString *str;
@property(nonatomic,strong)postValueBlock myBlock;

#import "secondViewController.h"

@interface secondViewController ()

@end

@implementation secondViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.view.backgroundColor=[UIColor grayColor];
    
    
    self.name1=[[UITextField alloc]initWithFrame:CGRectMake(100, 100, 100, 100)];
    self.name1.borderStyle=2;
    self.name1.text=self.str;
    //    self.name1.backgroundColor=[UIColor ];
    [self.view addSubview:self.name1];
    
    
    self.btn=[[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
    [self.btn setTitle:@"上一页" forState:0];
    [self.btn addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
    
    [self.view addSubview:self.btn];


}

-(void)back{
    
    
//    if (self.deletage!=nil) {
//        [self.deletage postValue:self.name1.text];
//
//    }
    
    
    if (self.myBlock) {
        self.myBlock(self.name1.text);
    }

    
    [self dismissViewControllerAnimated:YES completion:nil];

}

-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{

    [self.name1 resignFirstResponder];
}


-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField{

    if ([textField isFirstResponder]) {
        [textField resignFirstResponder];
    }
    return YES;
}
- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

把根视图转到第一个视图，最后代码和代理模式的一样，在AppDelegate的

本文主要是使用第一个文本框的值传递到第二个页面的文本框中，修改第二个页面文本框中的内容，同时又显示到第一个页面的文本框中，为属性复制都写在几种传值的里面（除了单例传值）

相关阅读:
mySQL优化方案
 java之自动过滤提交文本中的html代码script代码
 java小技术之生成二维码
 微信扫码支付功能详细教程————Java
java实现发送邮件服务器，SMTP协议发送邮件
 『重构--改善既有代码的设计』读书笔记----序
 Linux导航神器-----autojump
绘图时，根据size()和自定义rect编程的区别
 Qt中如何在QCursor移动的时候不触发moveEvent
Qt远程机开发时光标注意问题
原文地址：https://www.cnblogs.com/qianLL/p/5281611.html