回传值问题，一直都是困扰初学者的问题，今写者 代理、通知、block 三者的回传值做了一个小小的总结，
Main.storyboard 视图：
通过代码分别创建三个代表 代理、通知、block 的按钮，点击相应的按钮，会将相应的文本传入文本框中显示出来
代码如下：
1 // GWFMyDelegateBlockNotyView.h 2 // 回传值 3 4 #import <UIKit/UIKit.h> 5 @class GWFMyDelegateBlockNotyView; 6 7 //协议 8 @protocol GWFMyDelegateBlockNotyViewDelegate <NSObject> 9 10 //定义代理方法 11 -(void)GWFMyDelegateBlockNotyView:(GWFMyDelegateBlockNotyView *)view andString:(NSString *)string andImage:(UIImage *)image; 12 13 @end 14 15 @interface GWFMyDelegateBlockNotyView : UIView 16 17 //定义 id 属性 18 @property (nonatomic,weak) id <GWFMyDelegateBlockNotyViewDelegate> myDelegate; 19 20 //添加 block 属性 21 @property (nonatomic,copy) void (^myBlock)(NSString *,UIImage *); 22 23 @end
1 // GWFMyDelegateBlockNotyView.m
2 // 回传值
3
4 #import "GWFMyDelegateBlockNotyView.h"
5 #import "SVProgressHUD.h"
6 #import "MBProgressHUD+Ex.h"
7
8 @implementation GWFMyDelegateBlockNotyView
9
10 - (instancetype)init
11 {
12 self = [super init];
13 if (self) {
14
15 #pragma ==================================== 代理传值按钮
16
17 //1.创建 delegateBtn
18 UIButton *deleBtn = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
19 //设置背景颜色
20 deleBtn.backgroundColor = [UIColor redColor];
21 //设置title
22 [deleBtn setTitle:@"代理传值" forState:UIControlStateNormal];
23 //设置 title 的颜色
24 [deleBtn setTitleColor:[UIColor blueColor] forState:UIControlStateNormal];
25
26 //添加到控制器上
27 [self addSubview:deleBtn];
28
29 //添加 deleBtn 的监听事件
30 [deleBtn addTarget:self action:@selector(deleBtnClick) forControlEvents:UIControlEventTouchUpInside];
31
32 #pragma ==================================== Block传值按钮
33
34 //2.创建 Block 按钮
35 UIButton *blockBtn = [[UIButton alloc] initWithFrame:CGRectMake(110, 0, 100, 100)];
36 //设置背景颜色
37 blockBtn.backgroundColor = [UIColor greenColor];
38 //设置 title
39 [blockBtn setTitle:@"Block传值" forState:UIControlStateNormal];
40 //设置 title 的颜色
41 [blockBtn setTitleColor:[UIColor blueColor] forState:UIControlStateNormal];
42
43 //添加到控制器上
44 [self addSubview:blockBtn];
45
46 //添加 blockBtn 的监听事件
47 [blockBtn addTarget:self action:@selector(blockBtnClick) forControlEvents:UIControlEventTouchUpInside];
48
49 #pragma ==================================== 通知传值按钮
50
51 //3.创建 notyBtn
52 UIButton *notyBtn = [[UIButton alloc] initWithFrame:CGRectMake(215, 0, 100, 100)];
53 //设置背景颜色
54 notyBtn.backgroundColor = [UIColor blueColor];
55 //设置 title
56 [notyBtn setTitle:@"通知传值" forState:UIControlStateNormal];
57 //设置 notyBtn 的 title 的颜色
58 [notyBtn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
59
60 //添加到控制器上
61 [self addSubview:notyBtn];
62
63 //添加 notyBtn 的监听事件
64 [notyBtn addTarget:self action:@selector(notyBtnClick) forControlEvents:UIControlEventTouchUpInside];
65
66 }
67 return self;
68 }
69
70 //实现按钮的点击事件
71 #pragma mark -------代理
72
73 -(void)deleBtnClick {
74 NSString *myText = @"这是代理传来的值";
75 UIImage *image = [UIImage imageNamed:@"0 (3)"];
76
77 //判断代理
78 if ([self.myDelegate respondsToSelector:@selector(GWFMyDelegateBlockNotyView:andString:andImage:)]) {
79
80 //执行代理
81 [self.myDelegate GWFMyDelegateBlockNotyView:self andString:myText andImage:image];
82
83 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
84
85 [SVProgressHUD showWithStatus:@"正在连接..." maskType:SVProgressHUDMaskTypeBlack];
86 });
87
88 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
89
90 [SVProgressHUD dismiss];
91 UIApplication *app = [UIApplication sharedApplication];
92 NSURL *url = [NSURL URLWithString:@"http://www.dianping.com"];
93 [app openURL:url];
94
95 });
96 }
97 }
98
99 #pragma mark -------block
100
101 -(void)blockBtnClick {
102 NSString *myText = @"这是Block传来的值";
103 UIImage *image = [UIImage imageNamed:@"0 (2)"];
104 self.myBlock(myText,image);
105
106 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
107
108 [SVProgressHUD showWithStatus:@"正在连接..." maskType:SVProgressHUDMaskTypeBlack];
109 });
110
111 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
112
113 [SVProgressHUD dismiss];
114
115 UIApplication *app = [UIApplication sharedApplication];
116 NSURL *url = [NSURL URLWithString:@"http://www.10010.com"];
117 [app openURL:url];
118
119 });
120 }
121
122 #pragma mark --------通知
123
124 -(void)notyBtnClick {
125 NSString *myText = @"这是通知传来的值";
126 UIImage *image = [UIImage imageNamed:@"0 (7)"];
127
128 //发布一个通知
129 [[NSNotificationCenter defaultCenter] postNotificationName:@"myNoty" object:nil userInfo:@{@"myText":myText,@"image":image}];
130
131 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
132
133 [SVProgressHUD showWithStatus:@"正在连接..." maskType:SVProgressHUDMaskTypeBlack];
134 });
135
136 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
137
138 [SVProgressHUD dismiss];
139
140 UIApplication *app = [UIApplication sharedApplication];
141 NSURL *url = [NSURL URLWithString:@"http://www.youku.com"];
142 [app openURL:url];
143
144 });
145 }
146
147 @end
控制器中：
1 // ViewController.m
2 // 回传值
3
4 #import "ViewController.h"
5 #import "GWFMyDelegateBlockNotyView.h"
6
7 @interface ViewController ()<GWFMyDelegateBlockNotyViewDelegate>
8
9 @property (weak, nonatomic) IBOutlet UILabel *myLabel;
10 @property (weak, nonatomic) IBOutlet UIImageView *myImageView;
11
12 @end
13
14 @implementation ViewController
15
16 - (void)viewDidLoad {
17 [super viewDidLoad];
18
19 self.view.backgroundColor = [UIColor orangeColor];
20 //添加 myView
21 GWFMyDelegateBlockNotyView *myView = [[GWFMyDelegateBlockNotyView alloc] init];
22 myView.frame = CGRectMake(30, 150, 300, 200);
23 [self.view addSubview:myView];
24
25 //设置代理
26 myView.myDelegate = self;
27
28 //block
29 myView.myBlock = ^(NSString *block,UIImage *myBlock){
30 self.myLabel.text = block;
31 self.myImageView.image = myBlock;
32 };
33
34 //添加通知的一个监听事件
35 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(noty:) name:@"myNoty" object:nil];
36
37 }
38
39 //实现代理方法
40 -(void)GWFMyDelegateBlockNotyView:(GWFMyDelegateBlockNotyView *)view andString:(NSString *)string andImage:(UIImage *)image {
41 self.myLabel.text = string;
42 self.myImageView.image = image;
43 }
44
45 //实现通知的监听方法
46 -(void)noty:(NSNotification *)noty {
47 self.myLabel.text = noty.userInfo[@"myText"];
48 self.myImageView.image = noty.userInfo[@"image"];
49 }
50
51 @end
执行结果：
1> 点击代理按钮后：
2> 点击通知按钮后:
3>点击block按钮后:
时间： 2024-10-24 17:25:53