代理实现界面跳转传值

1．委托需要做的工作有：

 1.1定义协议与方法1.2声明委托变量 1.3设置代理 1.4通过委托变量调用委托方法

2．代理需要做的工作有:

 2.1遵循协议 2.2实现委托方法

下面讲解一下使用委托实现页面传值的解决方法：
加入我们有两个ViewController 分别为：ViewController和 ReceiveViewController

在viewController中
@protocol sendValueDelegate ／／定义（——）协议与（——）方法
-(void)sendValue:(NSString *)value;
@end

@interface ViewController : UIViewController

@property (retain , nonatomic) id ／／（——）声明一个代理 valueDelegate;
@end

在ViewController文件的.m中

import “ViewController.h”

import “ReceiveViewController.h”

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UITextField *sendValue;
- (IBAction)buttonClick:(id)sender;

@end

@implementation ViewController

• (void)viewDidLoad {
  [super viewDidLoad];
  }
• (IBAction)buttonClick:(id)sender {
  ReceiveViewController *receiveVC = [[ReceiveViewController alloc]initWithNibName:@”ReceiveViewController” bundle:nil];
  self.valueDelegate = receiveVC;／／（——）设置代理
  [self.valueDelegate sendValue:self.sendValue.text];用（——）代理实现协议委托的方法，并把要传的值传过去，以便在下一个界面中去接收
  //[self.navigationController pushViewController:receiveVC animated:YES];
  [self presentViewController:receiveVC animated:YES completion:nil];
  NSLog(@”==”);
  }
  @end
  在ReceiveViewController.h中

import

import “ViewController.h”

@interface ReceiveViewController : UIViewController／／（——）遵循设置代理的协议
@property (weak, nonatomic) IBOutlet UILabel *receiveValue;
@property (weak, nonatomic) IBOutlet UITextField *textField;
@end

import “ReceiveViewController.h”

@interface ReceiveViewController ()

@property (strong, nonatomic)UILabel *label;

@end

@implementation ReceiveViewController

• (void)viewDidLoad {
  [super viewDidLoad];

}
／／（——）实现委托的方法
-(void)sendValue:(NSString *)value{
self.label = [[UILabel alloc]initWithFrame:CGRectMake(100, 100, 100, 30)];
[self.label setBackgroundColor:[UIColor grayColor]];
[self.view addSubview:self.label];
[self.label setTintColor:[UIColor redColor]];
self.receiveValue.text = value;

self.textField.text = value;NSLog(@"=====%@", value);NSString *str = value;NSLog(@"传过来的值是：%@", str);self.label.text = str ;

}
@end