oc协议与代理简单例子

1 #import <Foundation/Foundation.h>
2 
3 @protocol BuyticketsDelegate <NSObject>
4 
5 @required
6 - (void) check;
7 
8 @end

 1 #import "Buytickets.h"
 2 @interface Agents : NSObject<BuyticketsDelegate>
 3 
 4 @end
 5 
 6 
 7 @implementation Agents
 8 
 9 - (void)check{
10     NSLog(@"还有剩票");
11 }
12 
13 @end

 1 @interface Person : NSObject
 2 
 3 @property(nonatomic, assign)id<BuyticketsDelegate>delegate;
 4 
 5 - (void)buy;
 6 
 7 @end
 8 
 9 
10 #import "Person.h"
11 @implementation Person
12 
13 - (void)buy{
14     [_delegate check];
15 }
16 
17 @end

 1 int main(int argc, const char * argv[]) {
 2    @autoreleasepool {
 3        
 4        Person *person = [[Person alloc]init];
 5        Agents *age = [[Agents alloc]init];
 6        person.delegate = age;
 7        [person buy];
 8 
 9         
10     }
11     return 0;
12 }