iOS:视图切换的第一种方式：模态视图

 1 #import "ViewController.h"
 2 #import "SecondViewController.h"
 3 @interface ViewController ()
 4 @property (weak, nonatomic) IBOutlet UITextField *TextField;
 5 
 6 @end
 7 
 8 @implementation ViewController
 9 -(void)setTextWithBackInfo:(NSString *)info
10 {
11     self.TextField.text = info;
12 }
13 - (void)viewDidLoad {
14     [super viewDidLoad];
15 }
16 //纯代码创建模态显示
17 - (IBAction)forwardClicked:(UIButton *)sender
18 {
19     //首先创建模态显示的控制器
20     //从storyboard中加载控制器
21     UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
22     
23     //匹配storyboard的标识符
24     SecondViewController *secondVC = [storyboard instantiateViewControllerWithIdentifier:@"Second"];
25     
26     //正向传数据
27     secondVC.info = self.TextField.text;
28     
29     //显示模态窗口
30     [self presentViewController:secondVC animated:YES completion:nil];
31 }
32 
33 @end

1 #import <UIKit/UIKit.h>
2 
3 @interface ViewController : UIViewController
4 
5 -(void)setTextWithBackInfo:(NSString *)info;
6 @end

 1 #import "ViewController.h"
 2 #import "SecondViewController.h"
 3 @interface ViewController ()<SecondViewControllerDelegate>
 4 @property (weak, nonatomic) IBOutlet UITextField *TextField;
 5 
 6 @end
 7 
 8 @implementation ViewController
 9 -(void)setTextWithBackInfo:(NSString *)info
10 {
11     self.TextField.text = info;
12 }
13 - (void)viewDidLoad {
14     [super viewDidLoad];
15 }
16 //纯代码创建模态显示
17 - (IBAction)forwardClicked:(UIButton *)sender
18 {
19     //首先创建模态显示的控制器
20     //从storyboard中加载控制器
21     UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
22     
23     //匹配storyboard的标识符
24     SecondViewController *secondVC = [storyboard instantiateViewControllerWithIdentifier:@"Second"];
25     
26     //正向传数据
27     secondVC.info = self.TextField.text;
28     
29     //为了接受反向数据,将自己设置为模态窗口的代理,很好的降低了模态窗口的耦合性
30     secondVC.delegate = self;
31     
32     //显示模态窗口
33     [self presentViewController:secondVC animated:YES completion:nil];
34 }
35 
36 #pragma mark -SecondViewController的代理方法
37 //通过代理接受模态窗口反向传回的数据
38 -(void)SecondVC:(SecondViewController *)vc didFinishedWithInfo:(NSString *)info
39 {
40     self.TextField.text = info;
41 }
42 @end

 1 #import <UIKit/UIKit.h>
 2 @protocol SecondViewControllerDelegate;
 3 @interface SecondViewController : UIViewController
 4 @property (weak, nonatomic) IBOutlet UILabel *label;
 5 @property (copy,nonatomic)NSString *info;
 6 //2.添加代理属性
 7 @property (weak,nonatomic)id<SecondViewControllerDelegate> delegate;
 8 @end
 9 
10 
11 //1.定义协议
12 @protocol SecondViewControllerDelegate
13 
14 -(void)SecondVC:(SecondViewController*)vc didFinishedWithInfo:(NSString*)info;
15 
16 @end

 1 #import "SecondViewController.h"
 2 
 3 @interface SecondViewController ()
 4 @property (weak, nonatomic) IBOutlet UITextField *textField;
 5 @end
 6 
 7 @implementation SecondViewController
 8 - (IBAction)backButtonClicked:(UIButton *)sender
 9 {
10     //self.presentedViewController  当前控制器模态出的窗口
11     //self.presentingViewController 模态出当前控制器的窗口
12     
13     
14     //3.通过代理反向传数据
15     [self.delegate SecondVC:self didFinishedWithInfo:self.textField.text];
16     
17     
18     //关闭模态窗口
19     [self.presentingViewController dismissViewControllerAnimated:YES completion:nil];
20     
21 }
22 
23 - (void)viewDidLoad {
24     [super viewDidLoad];
25     // Do any additional setup after loading the view.
26     
27     self.label.text = self.info;
28 }