ios 得用代理反向傳值

ios 得用代理反向傳值

應用情境：有時時候從介面A跳轉到介面B,介面B在返回的時候需要將處理的結果傳遞給A.

實現思路：1，定義一個負責傳值的協義，介面A擁有該協義屬性，並實現該協義中的方法

2，介面B也擁有該協義屬性（代理要求兩者都具有相同對象的引用 ），然後在返回的時候擷取介面A的引用指標，並且指定B中協義的調用目標為A,調用協義中的傳值方法.

具體代碼:

A的標頭檔 ：

#import

@protocol passValueDelegate

-(void) setValue:(NSString *)param;

@end

@interface ViewController :UIViewController

@propertyid passValueDelegate;

@end

A的實現檔案 :

#import "ViewController.h"

#import "ViewController2.h"

@interfaceViewController ()

{

}

@end

@implementation ViewController

- (void)viewDidLoad

{

[superviewDidLoad];

// Do any additional setup after loading the view, typically from a nib.

UIButton *btn =[UIButtonbuttonWithType:UIButtonTypeRoundedRect];

btn.frame=CGRectMake(100,100, 200,40);

[btn setTitle:@"btn"forState:UIControlStateNormal];

[btn addTarget:selfaction:@selector(btn)forControlEvents:UIControlEventTouchUpInside];

[self.viewaddSubview:btn];

self.view.backgroundColor=[UIColorredColor];

}

-(void) setValue:(NSString *)param{

NSLog(@"pass value is:%@",param);

}

-(void)btn

{

[self.navigationController pushViewController:[[ViewController2 alloc]init] animated:YES];

}

- (void)didReceiveMemoryWarning

{

[super didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end

B的標頭檔 ：

#import

@interface ViewController2 :UIViewController

@end

B的實現檔案:

#import "ViewController2.h"

#import "ViewController.h"

@interfaceViewController2 ()

@propertyid passValueDelegate;

@end

@implementation ViewController2

- (void)viewDidLoad

{

[superviewDidLoad];

UIButton *btn =[UIButtonbuttonWithType:UIButtonTypeRoundedRect];

btn.frame=CGRectMake(100,100, 200,40);

[btn setTitle:@"back"forState:UIControlStateNormal];

[btn addTarget:selfaction:@selector(btn)forControlEvents:UIControlEventTouchUpInside];

[self.viewaddSubview:btn];

}

-(void)btn

{

// NSLog(@"%@",self.navigationController.childViewControllers[0]);

self.passValueDelegate=self.navigationController.childViewControllers[0];

[self.navigationControllerpopToRootViewControllerAnimated:YES];

[self.passValueDelegatesetValue:@"123456789"];

}

- (void)didReceiveMemoryWarning

{

[superdidReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@end