ios常见的页面传值方式

iOS页面间的传值细分有很多种，基本的传值方式有三种：委托Delegate传值、通知NSNotification传值、Block传值，其他在项目中可能会遇到的还有：UserDefault或文件方式传值、单例模式传值、通过设置属性传值，再有其他的传值方式没有遇到使用过在此不做说明。场景适合，自己使用舒服就是好的方式。

　　在iOS开发的过程中，常见的页面跳转传值方式大致可以分为两种，现归纳总结一下：

　　第一种:OneViewController页面跳转到TwoViewController页面(即顺传)

　　方法：在TwoViewController页面的控制器中，编写对应的属性，在OneViewController页面跳转到TwoViewController页面的地方，给TwoViewController的属性赋值即可

1 /**
2  *  接收页面传递的值
3  */
4 @property(nonatomic,copy)NSString *text;

　　在A页面的试图控制器中

oneViewController的代码实例

@interface OneViewController ()

/**
 *  输入框
 */
@property(weak,nonatomic)UITextField *txtField;

@end

@implementation OneViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
#pragma mark - 创建UITextField
    
    //创建UITextField对象
    UITextField *txtField = [[UITextField alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
    
    //设置背景色
    txtField.backgroundColor = [UIColor whiteColor];
    
    //添加
    [self.view addSubview:txtField];
    
    //赋值
    _txtField = txtField;
    
#pragma mark - 创建btn
    
    //创建button对象
    UIButton *pushBtn = [[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
    
    //设置按钮位置
    pushBtn.center = self.view.center;
    
    //设置标题
    [pushBtn setTitle:@"跳转" forState:UIControlStateNormal];
    
    //添加按钮点击事件
    [pushBtn addTarget:self action:@selector(pushBtnClick) forControlEvents:UIControlEventTouchUpInside];
    
    //添加
    [self.view addSubview:pushBtn];
}

/**
 *  点击事件的方法
 */
- (void)pushBtnClick {
    
    //创建TwoViewController对象
    TwoViewController *twoVc = [[TwoViewController alloc]init];
    
    //接收oneViewController传递值
    twoVc.text = self.txtField.text;

    //执行push操作
    [self.navigationController pushViewController:twoVc animated:YES];
    
}
@end

　　第二种：A页面跳转到B页面，B页面再跳转回A页面

　　方法 ：主流方案

　　1）通过委托delegate的方式实现

　　　　1 在B页面设置代理协议，代理属性

　　　　2 在A页面设置代理对象，实现代理方法

　　　　3 在回到B页面调用代理方法完成质的传递

oneViewController.m的代码实例

 1 //遵守代理协议
 2 @interface OneViewController () <TwoViewControllerDelegate>
 3 
 4 /**
 5  *  文本框
 6  */
 7 @property(weak,nonatomic)UILabel *lable;
 8 
 9 @end
10 
11 @implementation OneViewController
12 
13 - (void)viewDidLoad {
14     [super viewDidLoad];
15     
16 #pragma mark - 创建UILable
17     
18     //创建UILable对象
19     UILabel *lable = [[UILabel alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
20     
21     //设置背景色
22     lable.backgroundColor = [UIColor whiteColor];
23     
24     //添加
25     [self.view addSubview:lable];
26     
27     //赋值
28     _lable = lable;
29     
30 #pragma mark - 创建btn
31     
32     //创建button对象
33     UIButton *pushBtn = [[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
34     
35     //设置按钮位置
36     pushBtn.center = self.view.center;
37     
38     //设置标题
39     [pushBtn setTitle:@"跳转到two" forState:UIControlStateNormal];
40     
41     //添加按钮点击事件
42     [pushBtn addTarget:self action:@selector(pushBtnClick) forControlEvents:UIControlEventTouchUpInside];
43     
44     //添加
45     [self.view addSubview:pushBtn];
46 }
47 
48 /**
49  *  点击事件的方法
50  */
51 - (void)pushBtnClick {
52     
53     //创建TwoViewController对象
54     TwoViewController *twoVc = [[TwoViewController alloc]init];
55     
56     //接收oneViewController传递值
57     twoVc.text = self.lable.text;
58     
59     //设置代理对象
60     twoVc.delegate = self;
61 
62     //执行push操作
63     [self.navigationController pushViewController:twoVc animated:YES];
64     
65 }
66 
67 /**
68  *  实现代理方法设置lable文本
69  *
70  *  @param text 传递值
71  */
72 -(void)setLableText:(NSString *)text {
73 
74     self.lable.text = text;
75 }
76 
77 @end

TwoViewController.h的代码实例

 1 #import <UIKit/UIKit.h>
 2 
 3 //代理协议
 4 @protocol TwoViewControllerDelegate <NSObject>
 5 
 6 @optional
 7 /**
 8  *  代理方法 给OneViewController的lable赋值
 9  */
10 - (void)setLableText:(NSString *)text;
11 
12 @end
13 
14 @interface TwoViewController : UIViewController
15 
16 /**
17  *  接收 A页面传递的值
18  */
19 @property(nonatomic,copy)NSString *text;
20 
21 /**
22  *  设置代理(为防止循环引用，此次采用了weak)
23  */
24 @property(nonatomic,weak)id <TwoViewControllerDelegate>delegate;
25 
26 @end

TwoViewController.m的代码实例 

#import "TwoViewController.h"

@interface TwoViewController ()

/**
 *  输入框
 */
@property(weak,nonatomic)UITextField *twoTxtField;
@end

@implementation TwoViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = [UIColor grayColor];
   
#pragma mark - 创建UILable
    //创建UITextField对象
    UITextField *txtField = [[UITextField alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
    
    //设置背景色
    txtField.backgroundColor = [UIColor whiteColor];
    
    //添加
    [self.view addSubview:txtField];
    
    //赋值
    _twoTxtField = txtField;
    
#pragma mark - 创建button
    
    //创建UIButton对象
    UIButton *btn = [[UIButton alloc]initWithFrame:CGRectMake(200, 200, 100, 100)];
    
    //设置button的位置
    btn.center = self.view.center;
    
    //设置button标题
    [btn setTitle:@"返回one" forState:UIControlStateNormal];
    
    //添加点击事件
    [btn addTarget:self action:@selector(returnToOne) forControlEvents:UIControlEventTouchUpInside];
    
    //添加
    [self.view addSubview:btn];
}

/**
 *  返回one 按钮点击事件
 *
 *  @param field oneViewController输入框
 */
- (void)returnToOne {

    //判断是否响应
    if ([self.delegate respondsToSelector:@selector(setLableText:)]) {
        
        //调用代理方法
        [self.delegate setLableText:self.twoTxtField.text];
    }
    
    //执行pop方法返回OneViewController页面
    [self.navigationController popToRootViewControllerAnimated:YES];

}


@end

效果：

         

代理方法实现传值过程中，最重要也是最容易忽略的，就是一定要设置delegate的指向。

（2）通知NSNotification传值方式实现

　　1 在OneViewController页面的控制器中注册通知，实现通知方法接收传递值(以子典形式传递)，通知结束并销毁通知

　　2 在TwoViewController页面的控制器中发送通知

OneViewController.m代码示例

 1 @interface OneViewController ()
 2 
 3 /**
 4  *  文本框
 5  */
 6 @property(weak,nonatomic)UILabel *lable;
 7 
 8 @end
 9 
10 @implementation OneViewController
11 
12 - (void)viewDidLoad {
13     [super viewDidLoad];
14 
15 #pragma mark - 注册通知
16     //注册通知 name参数就是指通知名
17     [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(setLableText:) name:@"setLableNsnotification" object:nil];
18     
19 #pragma mark - 创建UILable
20     
21     //创建UILable对象
22     UILabel *lable = [[UILabel alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
23     
24     //设置背景色
25     lable.backgroundColor = [UIColor whiteColor];
26     
27     //添加
28     [self.view addSubview:lable];
29     
30     //赋值
31     _lable = lable;
32     
33 #pragma mark - 创建btn
34     
35     //创建button对象
36     UIButton *pushBtn = [[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
37     
38     //设置按钮位置
39     pushBtn.center = self.view.center;
40     
41     //设置标题
42     [pushBtn setTitle:@"跳转到two" forState:UIControlStateNormal];
43     
44     //添加按钮点击事件
45     [pushBtn addTarget:self action:@selector(pushBtnClick) forControlEvents:UIControlEventTouchUpInside];
46     
47     //添加
48     [self.view addSubview:pushBtn];
49 }
50 
51 /**
52  *  点击事件的方法
53  */
54 - (void)pushBtnClick {
55     
56     //创建TwoViewController对象
57     TwoViewController *twoVc = [[TwoViewController alloc]init];
58     
59     //接收oneViewController传递值
60     twoVc.text = self.lable.text;
61 
62     //执行push操作
63     [self.navigationController pushViewController:twoVc animated:YES];
64     
65 }
66 
67 /**
68  *  实现通知方法设置lable文本
69  *
70  *  @param notification 通知信息
71  */
72 -(void)setLableText:(NSNotification *)notification {
73 
74     //创建一个字典用来传递通知信息
75     NSDictionary *nameDictionary = [notification userInfo]; self.lable.text = [nameDictionary objectForKey:@"text"];
76 }
77 
78 /**
79  *  使用结束 销毁通知
80  */
81 - (void)dealloc {
82 
83     //移除通知
84     [[NSNotificationCenter defaultCenter]removeObserver:self];
85 }
86 @end

TwoViewController.m代码示例

 1 @interface TwoViewController ()
 2 
 3 /**
 4  *  输入框
 5  */
 6 @property(weak,nonatomic)UITextField *twoTxtField;
 7 @end
 8 
 9 @implementation TwoViewController
10 
11 - (void)viewDidLoad {
12     [super viewDidLoad];
13     
14     self.view.backgroundColor = [UIColor grayColor];
15    
16 #pragma mark - 创建UILable
17     //创建UITextField对象
18     UITextField *txtField = [[UITextField alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
19     
20     //设置背景色
21     txtField.backgroundColor = [UIColor whiteColor];
22     
23     //添加
24     [self.view addSubview:txtField];
25     
26     //赋值
27     _twoTxtField = txtField;
28     
29 #pragma mark - 创建button
30     
31     //创建UIButton对象
32     UIButton *btn = [[UIButton alloc]initWithFrame:CGRectMake(200, 200, 100, 100)];
33     
34     //设置button的位置
35     btn.center = self.view.center;
36     
37     //设置button标题
38     [btn setTitle:@"返回one" forState:UIControlStateNormal];
39     
40     //添加点击事件
41     [btn addTarget:self action:@selector(returnToOne:) forControlEvents:UIControlEventTouchUpInside];
42     
43     //添加
44     [self.view addSubview:btn];
45 }
46 
47 /**
48  *  返回one 按钮点击事件
49  *
50  *  @param field oneViewController输入框
51  */
52 - (void)returnToOne:(id) sender {
53 
54     //发送通知
55     [[NSNotificationCenter defaultCenter]postNotificationName:@"setLableNsnotification" object:self userInfo:@{@"text" : self.twoTxtField.text}];
56     
57     //执行pop方法返回OneViewController页面
58     [self.navigationController popToRootViewControllerAnimated:YES];
59 
60 }
61 
62 
63 @end

效果相同，在此就不贴图了。

（3）block方式实现

　　1 在TwoViewController视图控制器中，定义一个block，参数为字符串

　　2 在OneViewController图显示，回调block

TwoViewController.h代码示例

 1 /**
 2  *  设置参数为NSString类型block 为myBlock
 3  */
 4 typedef void (^myBlock)(NSString *str);
 5 
 6 @interface TwoViewController : UIViewController
 7 
 8 /**
 9  *  接收 A页面传递的值
10  */
11 @property(nonatomic,copy)NSString *text;
12 
13 /**
14  * 定义一个myBlock 类型的block
15  */
16 @property(nonatomic,copy)myBlock block;
17 
18 @end

TwoViewController.m代码示例

 1 @interface TwoViewController ()
 2 
 3 /**
 4  *  输入框
 5  */
 6 @property(weak,nonatomic)UITextField *twoTxtField;
 7 @end
 8 
 9 @implementation TwoViewController
10 
11 - (void)viewDidLoad {
12     [super viewDidLoad];
13     
14     self.view.backgroundColor = [UIColor grayColor];
15    
16 #pragma mark - 创建UILable
17     //创建UITextField对象
18     UITextField *txtField = [[UITextField alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
19     
20     //设置背景色
21     txtField.backgroundColor = [UIColor whiteColor];
22     
23     //添加
24     [self.view addSubview:txtField];
25     
26     //赋值
27     _twoTxtField = txtField;
28     
29 #pragma mark - 创建button
30     
31     //创建UIButton对象
32     UIButton *btn = [[UIButton alloc]initWithFrame:CGRectMake(200, 200, 100, 100)];
33     
34     //设置button的位置
35     btn.center = self.view.center;
36     
37     //设置button标题
38     [btn setTitle:@"返回one" forState:UIControlStateNormal];
39     
40     //添加点击事件
41     [btn addTarget:self action:@selector(returnToOne) forControlEvents:UIControlEventTouchUpInside];
42     
43     //添加
44     [self.view addSubview:btn];
45 }
46 
47 /**
48  *  返回one 按钮点击事件
49  *
50  *  @param field oneViewController输入框
51  */
52 - (void)returnToOne {
53 
54     if (self.block) {
55         
56         //把当前输入框的text值给block
57         self.block(self.twoTxtField.text);
58     }
59     
60     //执行pop方法返回OneViewController页面
61     [self.navigationController popToRootViewControllerAnimated:YES];
62 
63 }
64 
65 
66 @end

OneViewController.m代码示例

 1 @interface OneViewController ()
 2 
 3 /**
 4  *  文本框
 5  */
 6 @property(weak,nonatomic)UILabel *lable;
 7 
 8 @end
 9 
10 @implementation OneViewController
11 
12 - (void)viewDidLoad {
13     [super viewDidLoad];
14 
15     
16 #pragma mark - 创建UILable
17     
18     //创建UILable对象
19     UILabel *lable = [[UILabel alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
20     
21     //设置背景色
22     lable.backgroundColor = [UIColor whiteColor];
23     
24     //添加
25     [self.view addSubview:lable];
26     
27     //赋值
28     _lable = lable;
29     
30 #pragma mark - 创建btn
31     
32     //创建button对象
33     UIButton *pushBtn = [[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
34     
35     //设置按钮位置
36     pushBtn.center = self.view.center;
37     
38     //设置标题
39     [pushBtn setTitle:@"跳转到two" forState:UIControlStateNormal];
40     
41     //添加按钮点击事件
42     [pushBtn addTarget:self action:@selector(pushBtnClick) forControlEvents:UIControlEventTouchUpInside];
43     
44     //添加
45     [self.view addSubview:pushBtn];
46 }
47 
48 /**
49  *  点击事件的方法
50  */
51 - (void)pushBtnClick {
52     
53     //创建TwoViewController对象
54     TwoViewController *twoVc = [[TwoViewController alloc]init];
55     
56     //接收oneViewController传递值
57     twoVc.text = self.lable.text;
58 
59     //回调block 拿到传递值设置lable的text
60     twoVc.block = ^(NSString *str){
61         
62         self.lable.text = str;
63     };
64     
65     //执行push操作
66     [self.navigationController pushViewController:twoVc animated:YES];
67     
68 }
69 
70 
71 
72 @end

以上就是三种基本的传值方式，也是我们在项目开发过程中最常使用的传值方式。

下面介绍两种在项目开发过程中也曾经遇到过，但是并不常用的传值方式。

（1）通过一个单例来传值

　　1 由于要用到单例模式，所以要创建一个继承于NSObject的DataSource类，存放数据

DataSource.h代码示例

 1 #import <Foundation/Foundation.h>
 2 @class DataSource;
 3 
 4 @interface DataSource : NSObject
 5 
 6 /**
 7  *  存放传递值的属性
 8  */
 9 @property (nonatomic, strong) NSString *text;
10 
11 /**
12  *  返回单例对象的类方法
13  */
14 +(DataSource*)sharedDataSource;
15 
16 @end

DataSource.m代码示例

#import "DataSource.h"

@implementation DataSource

+(DataSource *)sharedDataSource {
    
    static DataSource *dataSource = nil;
    
    static dispatch_once_t once;
    
    //dispach_once函数中的代码块只会被执行一次，而且还是线程安全的。
    dispatch_once(&once, ^{
        
        dataSource = [DataSource new];
    });
    
    return dataSource;
}

TwoViewController.m代码示例

 1 #import "TwoViewController.h"
 2 #import "DataSource.h"
 3 
 4 @interface TwoViewController ()
 5 
 6 /**
 7  *  输入框
 8  */
 9 @property(weak,nonatomic)UITextField *twoTxtField;
10 @end
11 
12 @implementation TwoViewController
13 
14 - (void)viewDidLoad {
15     [super viewDidLoad];
16     
17     self.view.backgroundColor = [UIColor grayColor];
18    
19 #pragma mark - 创建UILable
20     //创建UITextField对象
21     UITextField *txtField = [[UITextField alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
22     
23     //设置背景色
24     txtField.backgroundColor = [UIColor whiteColor];
25     
26     //添加
27     [self.view addSubview:txtField];
28     
29     //赋值
30     _twoTxtField = txtField;
31     
32 #pragma mark - 创建button
33     
34     //创建UIButton对象
35     UIButton *btn = [[UIButton alloc]initWithFrame:CGRectMake(200, 200, 100, 100)];
36     
37     //设置button的位置
38     btn.center = self.view.center;
39     
40     //设置button标题
41     [btn setTitle:@"返回one" forState:UIControlStateNormal];
42     
43     //添加点击事件
44     [btn addTarget:self action:@selector(returnToOne) forControlEvents:UIControlEventTouchUpInside];
45     
46     //添加
47     [self.view addSubview:btn];
48 }
49 
50 /**
51  *  返回one 按钮点击事件
52  *
53  *  @param field oneViewController输入框
54  */
55 - (void)returnToOne {
56 
57     //获取唯一实例对象
58     DataSource *dataSource = [DataSource sharedDataSource];
59     
60     //给单例对象属性赋值
61     dataSource.text = self.twoTxtField.text;
62     
63     //执行pop方法返回OneViewController页面
64     [self.navigationController popToRootViewControllerAnimated:YES];
65 
66 }
67 
68 
69 @end

OneViewController.m代码示例

 1 #import "OneViewController.h"
 2 #import "TwoViewController.h"
 3 #import "DataSource.h"
 4 
 5 @interface OneViewController ()
 6 
 7 /**
 8  *  文本框
 9  */
10 @property(weak,nonatomic)UILabel *lable;
11 
12 @end
13 
14 @implementation OneViewController
15 
16 - (void)viewDidLoad {
17     [super viewDidLoad];
18 
19     
20 #pragma mark - 创建UILable
21     
22     //创建UILable对象
23     UILabel *lable = [[UILabel alloc]initWithFrame:CGRectMake(self.view.center.x - 50, self.view.center.y - 100, 100, 30)];
24     
25     //设置背景色
26     lable.backgroundColor = [UIColor whiteColor];
27     
28     //添加
29     [self.view addSubview:lable];
30     
31     //赋值
32     _lable = lable;
33     
34 #pragma mark - 创建btn
35     
36     //创建button对象
37     UIButton *pushBtn = [[UIButton alloc]initWithFrame:CGRectMake(200, 300, 100, 100)];
38     
39     //设置按钮位置
40     pushBtn.center = self.view.center;
41     
42     //设置标题
43     [pushBtn setTitle:@"跳转到two" forState:UIControlStateNormal];
44     
45     //添加按钮点击事件
46     [pushBtn addTarget:self action:@selector(pushBtnClick) forControlEvents:UIControlEventTouchUpInside];
47     
48     //添加
49     [self.view addSubview:pushBtn];
50 }
51 
52 /**
53  *  点击事件的方法
54  */
55 - (void)pushBtnClick {
56     
57     //创建TwoViewController对象
58     TwoViewController *twoVc = [[TwoViewController alloc]init];
59     
60     //接收oneViewController传递值
61     twoVc.text = self.lable.text;
62 
63     
64     //执行push操作
65     [self.navigationController pushViewController:twoVc animated:YES];
66     
67 }
68 
69 
70 -(void)viewDidAppear:(BOOL)animated{
71     
72     [super viewDidAppear:animated];
73     
74     //获取唯一实例
75     DataSource *dataSource = [DataSource sharedDataSource];
76     
77     //判断单例对象的属性值是否为空
78     if ([dataSource.text length] != 0) {
79         
80         //把单例对象的属性值赋值给lable
81         self.lable.text = dataSource.text;
82      
83         //把单例对象属性值清空
84         dataSource.text = @"";
85         
86      }
87 }
88 
89 @end

（2）NSUserdefault来传值，这种传值方法并不常用，代码量也比较少就不粘贴详细代码了，当作了解就阔以啦。

OneViewController.m示例代码

 1 -(void)viewDidAppear:(BOOL)animated{
 2     
 3     [super viewDidAppear:animated];
 4     
 5      if ([[[NSUserDefaults standardUserDefaults] objectForKey:@"myLableText"] length] != 0){
 6      
 7         self.lable.text = [[NSUserDefaults standardUserDefaults] objectForKey:@"myLableText"]; [[NSUserDefaults standardUserDefaults] setObject:@"" forKey:@"myLableText"];
 8      }
 9     
10 }

TwoViewController.m示例代码

 1 /**
 2  *  返回one 按钮点击事件
 3  *
 4  *  @param field oneViewController输入框
 5  */
 6 - (void)returnToOne {
 7 
 8    [[NSUserDefaults standardUserDefaults] setObject:self.twoTxtField.text forKey:@"myLableText"];
 9     
10     //执行pop方法返回OneViewController页面
11     [self.navigationController popToRootViewControllerAnimated:YES];
12 
13 }