页面之间传值(单例传值)(自己使用)

首先创建2个新界面 ， 然后创建一个类，如下图



然后在AppDeleate.h

#import <UIKit/UIKit.h>
#import "FirstViewController.h"

@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;

@end

然后在AppDeleate.m中

#import "AppDelegate.h"

@interface AppDelegate ()

@end

@implementation AppDelegate

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

然后进入AppStatus.h

#import <Foundation/Foundation.h>

@interface AppStatus : NSObject

@property(strong ,nonatomic)NSString *contextStr;
+(AppStatus *)shareInstance;

@end

AppStatus.m

#import "AppStatus.h"

@implementation AppStatus

@synthesize contextStr = _contextStr;

static AppStatus *_instance = nil;

+(AppStatus *)shareInstance
{
if (_instance==nil) {
_instance=[[super alloc]init];
}
return _instance;
}
-(id)init
{
if (self=[super init]) {

}
return self;
}

@end

FirstViewController.h中

#import <UIKit/UIKit.h>
#import "SecondViewController.h"
#import "AppStatus.h"

@interface FirstViewController : UIViewController<UITextFieldDelegate>

@property(strong,nonatomic) UITextField *text1;
@property(strong,nonatomic) UIButton *btn1;

@end

FirstViewController.m中

#import "FirstViewController.h"

@interface FirstViewController ()

@end

@implementation FirstViewController

- (void)viewDidLoad {
[super viewDidLoad];

self.view.backgroundColor=[UIColor greenColor];

self.text1=[[UITextField alloc]initWithFrame:CGRectMake(100, 200, 200, 60)];

self.text1.borderStyle=1;

[self.view addSubview:self.text1];

self.text1.delegate=self;
self.btn1=[[UIButton alloc]initWithFrame:CGRectMake(130, 300, 150, 60)];

[self.btn1 setTitle:@"下一页" forState:0];

[self.btn1 setTitleColor:[UIColor blackColor ] forState:0];

[self.btn1 addTarget:self action:@selector(nextpage) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:self.btn1];

}

-(void)nextpage
{
[AppStatus shareInstance].contextStr=self.text1.text;
SecondViewController *secondvc=[[SecondViewController alloc]init];

[self presentViewController:secondvc animated:YES completion:^{
NSLog(@"ok");
}];
}

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

return YES;
}

-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];

self.text1.text=[AppStatus shareInstance].contextStr;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];

SecondViewController.h

#import <UIKit/UIKit.h>
#import "AppStatus.h"

@interface SecondViewController : UIViewController<UITextFieldDelegate>

@property(strong,nonatomic) UITextField *text2;
@property(strong,nonatomic) UIButton *btn2;

@end

SecondViewController.m

#import "SecondViewController.h"

@interface SecondViewController ()

@end

@implementation SecondViewController

- (void)viewDidLoad {
[super viewDidLoad];
self.view.backgroundColor=[UIColor redColor];

self.text2=[[UITextField alloc]initWithFrame:CGRectMake(100, 200, 200, 60)];

self.text2.borderStyle=1;

[self.view addSubview:self.text2];

self.text2.delegate=self;

self.text2.text=[AppStatus shareInstance].contextStr;

self.btn2=[[UIButton alloc]initWithFrame:CGRectMake(130, 300, 150, 60)];

[self.btn2 setTitle:@"返回" forState:0];

[self.btn2 setTitleColor:[UIColor colorWithRed:0.038 green:0.249 blue:1.000 alpha:1.000] forState:0];

[self.btn2 addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:self.btn2];
}

-(void)back
{
[AppStatus shareInstance].contextStr=self.text2.text;
[self dismissViewControllerAnimated:YES completion:nil];
}
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
if ([textField isFirstResponder]) {
[textField resignFirstResponder];
}

[self dismissViewControllerAnimated:YES completion:nil];

return YES;
}

-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];

self.text2.text=[AppStatus shareInstance].contextStr;
}

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];