ios中利用委托在二个视图间传值

1、定义协议

UIViewPassValueDelegate.h

1 #import <Foundation/Foundation.h>
2 
3 @protocol UIViewPassValueDelegate <NSObject>
4 -(void)passValue:(NSString *)value1;
5 @end

2、A视图定义

 1 #import "UIViewPassValueDelegate.h"
 2 
 3 @interface AViewController : UIViewController<UIViewPassValueDelegate>
 4 
 5 -(IBAction)buttonClick:(id)sender;
 6 
 7 -(void)passValue:(NSString *)value1{
 8     NSLog(@"A get value is %@",value1);
 9 }
10 
11 -(IBAction)buttonClick:(id)sender{
12     BViewController *b = [[BViewController alloc] init];
13     b.delegate = self;  // 将A作为一个变量传给B，这样在B中对delegate的任何操作其实就是对A的操作。
14     [self presentViewController:b animated:YES completion:nil];
15 }

3、B视图定义

 1 #import "UIViewPassValueDelegate.h"
 2 
 3 NSObject<UIViewPassValueDelegate> *delegate;
 4 @property (nonatomic,retain) NSObject<UIViewPassValueDelegate> *delegate;
 5 - (IBAction)buttonClick:(id)sender;
 6 
 7 @synthesize delegate;
 8 -(IBAction)buttonClick:(id)sender{
 9     [delegate passValue:@"ddd"];
10     NSLog(@"B text = ddd");
11     [self dismissViewControllerAnimated:YES completion:nil];
12 }

这样我点击B视图的按钮时就可以将值传给A视图了。