iOS 传值

属性传值 将A页面所拥有的信息通过属性传递到B页面使用

B页面定义了一个naviTitle属性，在A页面中直接通过属性赋值将A页面中的值传到B页面。

A页面DetailViewController.h文件

#import <UIKit/UIKit.h>

#import "DetailViewController.h"

@interface RootViewController :UIViewController<ChangeDelegate>

{

UITextField *tf;

}

@end

A RootViewController.m页面实现文件

#import "RootViewController.h"

#import "DetailViewController.h"

@interface RootViewController ()

@end

@implementation RootViewController

//核心代码

-(void)loadView

{

UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];

btn.frame = CGRectMake(0, 0, 100, 30);

[btn setTitle:@"Push" forState:0];

[btn addTarget:self action:@selector(pushAction:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:btn];

}

-(void)pushAction:(id)sender

{

tf = (UITextField *)[self.viewviewWithTag:1000];

//导航push到下一个页面

//pushViewController 入栈引用计数+1，且控制权归系统

DetailViewController *detailViewController = [[DetailViewControlleralloc]init];

//属性传值，直接属性赋值

detailViewController.naviTitle =tf.text;

//导航push到下一个页面

[self.navigationControllerpushViewController:detailViewController animated:YES];

[detailViewControllerrelease];

}

B页面DetailViewController.h文件

#import <UIKit/UIKit.h>

@interface DetailViewController :UIViewController

{

UITextField *textField;

NSString *_naviTitle;

}

@property(nonatomic,retain)NSString *naviTitle;

@end

B页面.m实现文件

#import "DetailViewController.h"

@interface DetailViewController ()

@end

@implementation DetailViewController

@synthesize naviTitle =_naviTitle;

-(void)loadView

{

self.view =
[[[UIViewalloc]initWithFrame:CGRectMake(0,0, 320,480)]autorelease];

self.title = self.naviTitle ;

}

代理传值

A页面push到B页面，如果B页面的信息想回传（回调）到A页面，用用代理传值，其中B定义协议和声明代理，A确认并实现代理，A作为B的代理

A页面RootViewController.h文件

#import <UIKit/UIKit.h>

#import "DetailViewController.h"

@interface RootViewController : UIViewController<ChangeDelegate>

{

UITextField *tf;

}

@end

A页面RootViewController.m实现文件

#import "RootViewController.h"

#import "DetailViewController.h"

@interface RootViewController ()

@end

@implementation RootViewController

//核心代码

-(void)loadView

{

UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];

btn.frame = CGRectMake(0, 0, 100, 30);

[btn setTitle:@"Push" forState:0];

//A页面push到B页面

[btn addTarget:self action:@selector(pushAction:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:btn];

}

-(void)pushAction:(id)sender

{

tf = (UITextField *)[self.view viewWithTag:1000];

//导航push到下一个页面

//pushViewController 入栈引用计数+1，且控制权归系统

DetailViewController *detailViewController = [[DetailViewController alloc]init];

//代理传值

detailViewController.delegate =self;//让其自身作为代理人

//导航push到下一个页面

[self.navigationController pushViewController:detailViewController animated:YES];

[detailViewController release];

}

//实现代理方法

-(void)changeTitle:(NSString *)aStr

{

tf = (UITextField *)[self.view viewWithTag:1000];

tf.text = aStr;//将从B页面传入的参数赋给A页面中的TextField

tf.text = aStr;

}

B页面DetailViewController.m文件

#import <UIKit/UIKit.h>

@interface DetailViewController : UIViewController

{

UITextField *textField;

//定义代理

id<ChangeDelegate>_delegate;

}

@property(nonatomic,assign)id<ChangeDelegate>
delegate;

@end

//定义协议

@protocol ChangeDelegate <NSObject>

-(void)changeTitle:(NSString *)aStr;//协议方法

@end

B页面DetailViewController.h实现文件

#import "DetailViewController.h"

@interface DetailViewController ()

@end

@implementation DetailViewController

-(void)loadView

{

self.view =
[[[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)]autorelease];

UIBarButtonItem *doneItem = [[UIBarButtonItemalloc]initWithBarButtonSystemItem:UIBarButtonSystemItemDonetarget:selfaction:@selector(doneAction:)];

self.navigationItem.rightBarButtonItem =
doneItem;

[doneItemrelease];

}

//pop回前一个页面

-(void)doneAction:(id)sender

{

if (self.delegate && [self.delegaterespondsToSelector:@selector(changeTitle:)])//若代理存在且响应了changeTitle这个方法

{

//[self.delegate changeTitle:textField.text];

[self.delegatechangeTitle:textField.text];//将textField.text参数传给changeTitle方法 让代理，也就是A页面去实现这个方法

NSLog(@"%@",self.navigationController.viewControllers);

[self.navigationControllerpopViewControllerAnimated:YES];

}

}

单例传值（实现共享）

AppStatus.h 创建一个单例类 AppStatus

#import <Foundation/Foundation.h>

@interface AppStatus : NSObject

{

NSString *_contextStr;

}

@property(nonatomic,retain)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;

}

-(void)dealloc

{

[super dealloc];

}

@end

A页面RootViewController.h

#import "RootViewController.h"

#import "DetailViewController.h"

#import "AppStatus.h"

@interface RootViewController ()

@end

@implementation RootViewController

-(void)loadView

{

//核心代码

UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];

btn.frame = CGRectMake(0, 0, 100, 30);

[btn setTitle:@"Push" forState:0];

[btn addTarget:self action:@selector(pushAction:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:btn];

}

-(void)pushAction:(id)sender

{

tf = (UITextField *)[self.view viewWithTag:1000];

//单例传值 将要传递的信息存入单例中（共享中）

// [[AppStatus shareInstance]setContextStr:tf.text]; 跟下面这种写法是等价的

[AppStatus shareInstance].contextStr = tf.text;

//导航push到下一个页面

//pushViewController 入栈引用计数+1，且控制权归系统

DetailViewController *detailViewController = [[DetailViewController alloc]init];

//导航push到下一个页面

[self.navigationController pushViewController:detailViewController animated:YES];

[detailViewController release];
}

@end

B页面DetailViewController.h

#import <UIKit/UIKit.h>

@protocol ChangeDelegate;//通知编译器有此代理

@interface DetailViewController : UIViewController

{

UITextField *textField;

}

@end

B页面DetailViewController.m

#import "DetailViewController.h"

#import "AppStatus.h"

@interface DetailViewController ()

@end

@implementation DetailViewController

@synthesize naviTitle = _naviTitle;

-(void)loadView

{

self.view =
[[[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)]autorelease];

//单例

self.title = [AppStatus shareInstance].contextStr;

textField = [[UITextField alloc]initWithFrame:CGRectMake(100, 100, 150, 30)];

textField.borderStyle = UITextBorderStyleLine;

[self.view addSubview:textField];

[textField release];

UIBarButtonItem *doneItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDonetarget:self action:@selector(doneAction:)];

self.navigationItem.rightBarButtonItem =
doneItem;

[doneItem release];

}

//这个方法是执行多遍的 相当于刷新view

-(void)viewWillAppear:(BOOL)animated

{

[super viewWillAppear:animated];

tf = (UITextField *)[self.view viewWithTag:1000];

tf.text =
[AppStatus shareInstance].contextStr;

}

//pop回前一个页面

-(void)doneAction:(id)sender

{

// 单例传值

[AppStatus shareInstance].contextStr = textField.text;

[self.navigationController popToRootViewControllerAnimated:YES];
}

通知传值 谁要监听值的变化，谁就注册通知 特别要注意，通知的接受者必须存在这一先决条件

A页面RootViewController.h

#import <UIKit/UIKit.h>

#import "DetailViewController.h"

@interface RootViewController : UIViewController<ChangeDelegate>

{

UITextField *tf;

}
@end

A页面RootViewController.m

#import "IndexViewController.h"

#import "DetailViewController.h"

#import "AppStatus.h"

@implementation IndexViewController

-(void)dealloc

{

[[NSNotificationCenter defaultCenter] removeObserver:self

name:@"CHANGE_TITLE" object:nil];

[super dealloc];

}

-(id)init

{

if (self = [super init])

{

[[NSNotificationCenter defaultCenter] addObserver:self

selector:@selector(change:)

name:@"CHANGE_TITLE"

object:nil];

}

return self;

}

-(void)change:(NSNotification *)aNoti

{

// 通知传值

NSDictionary *dic = [aNoti userInfo];

NSString *str = [dic valueForKey:@"Info"];

UITextField *tf = (UITextField *)[self.view viewWithTag:1000];

tf.text = str;

}

-(void)viewWillAppear:(BOOL)animated

{

[super viewWillAppear:animated];

/*

// 单例传值

UITextField *tf = (UITextField *)[self.view viewWithTag:1000];

tf.text = [AppStatus shareInstance].contextStr;

*/

}

@end

DetailViewController.h

#import <UIKit/UIKit.h>

@protocol ChangeDelegate;//通知编译器有此代理

@interface DetailViewController : UIViewController

{

UITextField *textField;

}

@end

DetailViewController.m

#import "DetailViewController.h"

#import "AppStatus.h"

@implementation DetailViewController

@synthesize naviTitle = _naviTitle;

-(void)loadView

{

UIBarButtonItem *doneItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDonetarget:self action:@selector(doneAction:)];

self.navigationItem.rightBarButtonItem =
doneItem;

[doneItem release];

}

// pop回前一个页面

-(void)doneAction:(id)sender

{

NSDictionary *dic = [NSDictionary dictionaryWithObject:textField.text forKey:@"Info"];

[[NSNotificationCenter defaultCenter] postNotificationName:@"CHANGE_TITLE" object:nil userInfo:dic];

[self.navigationController popViewControllerAnimated:YES];

}

Block

几种形式的Block

//无返回值

void (^block1) (void);

block1 = ^{

NSLog(@"bock demo");

};

block1();

//int返回类型

int (^block2) (void);

block2 = ^(void)

{

int a = 1 ,b =1;

int c = a+b;

return c;

};

//有返回 有参数

int (^block3)(int, int)= ^(int a, int b)

{

int c = a +b;

return c;

};

NSLog(@"bock=%d",block3(1,2));

//有返回值，有参数并且可以修改block之外变量的block

static int sum = 10;// __blcik and static关键字 或者 _block int sum = 10

int (^block4) (int) =^(int a)

{

sum=11;

int c = sum+a; //此时sum就是可以修改的了，若没加static或_block关键字则不能修改block之外变量

return c;

};

NSLog(@"block4= %d",block4(4));

Block传值

例如A(Ablock)页面的值传道B(Bblock)页面

在A页面中ABlock.h

@interface Ablock : UIViewController<UITableViewDelegate,UITableViewDataSource>

{

UITableView *_tableview;

UILabel *labe;

UIImageView *imagevies;

}

@end

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath

{

[_tableview deselectRowAtIndexPath:indexPath animated:YES];

Bblcok *bblock = [[Bblcok alloc] initwithBlock:Block_copy(^(NSString *aBlock){

labe.text = aBlock;

NSLog(@"%@",aBlock);

})];

bblock.imgeviews = imagevies.image;

bblock.String = labe.text;

[self.navigationController pushViewController:bblock animated:YES];

[bblock release];

}

在A页面中Bblock.h

#import <UIKit/UIKit.h>

typedef void (^MyBlock) (NSString *);

@interface Bblcok : UIViewController

{

UIImageView *image;

UITextField *aField;

UIButton *aButt;

NSString *_String;

id _imgeviews;

MyBlock myBlock;

}

@property(nonatomic,copy)MyBlock myBlock;

@property(nonatomic,retain) id imgeviews;

@property(nonatomic,retain) NSString *String;

-(id)initwithBlock:(MyBlock)aBlcok;

@end

//

// Bblcok.m

// Blcok

//

// Created by zhu on 13-8-12.

// Copyright (c) 2013年 Zhu Ji Fan. All rights reserved.

//

#import "Bblcok.h"

@interface Bblcok ()

@end

@implementation Bblcok

@synthesize imgeviews = _imgeviews , String = _String;

@synthesize myBlock = _myBlock;

-(id)initwithBlock:(MyBlock)aBlcok

{

if (self = [super init])

{

self.myBlock = aBlcok;

}

return self;

}

-(void) dealloc

{

[super dealloc];

}

-(void) loadView

{

UIControl *cont = [[UIControl alloc] initWithFrame:CGRectMake(0, 0, 320, 568-44)];

[cont addTarget:self action:@selector(Clcik) forControlEvents:UIControlEventTouchUpInside];

self.view = cont;

aField = [[UITextField alloc] initWithFrame:CGRectMake(60, 10, 160, 30)];

aField.borderStyle = UITextBorderStyleLine;

aField.placeholder = self.String;

[self.view addSubview:aField];

aButt = [UIButton buttonWithType:UIButtonTypeRoundedRect];

aButt.frame = CGRectMake(60, 50, 70, 30);

[aButt setTitle:@"修改" forState:0];

[aButt addTarget:self action:@selector(aButtClcik:) forControlEvents:UIControlEventTouchUpInside];

[self.view addSubview:aButt];

image = [[UIImageView alloc] initWithFrame:CGRectMake(60, 100, 210, 260)];

image.backgroundColor = [UIColor blueColor];

image.image = self.imgeviews;

[self.view addSubview:image];

[image release];

}

-(IBAction)aButtClcik:(id)sender

{

NSString *sting = aField.text;

myBlock(sting);

[self.navigationController popToRootViewControllerAnimated:YES];

}

-(void)Clcik

{

[aField resignFirstResponder];

}

- (void)viewDidLoad

{

[super viewDidLoad];

// Do any additional setup after loading the view.

}

- (void)didReceiveMemoryWarning

{

[super didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end