题目-通知-NSNoticafiction

Person.h

#import <Foundation/Foundation.h>

@interface Person : NSObject
@property(nonatomic,copy)NSString*name;
@property(nonatomic,assign)long int ID;
-(void)addObserver;//添加观察者
-(void)postNotification;//发通知
-(void)saySomething;
-(instancetype)initWithName:(NSString*)name andID:(long int)ID;
@end

Person.m

#import "Person.h"

@implementation Person

- (instancetype)initWithName:(NSString *)name andID:(long)ID
{
    self = [super init];
    if (self) {
        _name=name;
        _ID=ID;
    }
    return self;
}

//添加观察者
/*
 第一个参数:观察者
 第二个参数:回调方法
 第三个参数:通知的唯一标识
 第四个参数:发布者
 */
-(void)addObserver{

    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(gotoMeeting:) name:@"MEETING" object:nil];
}

//实现回调函数
-(void)gotoMeeting:(NSNotification*)notification{
    NSLog(@"%@",notification.userInfo);
   //notification.userInfo=@{@"date":@"8-20",@"classMeeting":@"kaoshi"}
    [self saySomething];
}

-(void)saySomething{}
//发通知
-(void)postNotification{
    [[NSNotificationCenter defaultCenter]postNotificationName:@"MEETING" object:nil userInfo:@{@"date":@"8-20",@"class Meeting":@"kaoshi"}];
    

}

@end

Teacher.h

#import "Person.h"

@interface Teacher : Person
@property(nonatomic,copy)NSString*subject;
-(instancetype)initWithName:(NSString *)name andID:(long)ID andSubject:(NSString*)subject;
@end

Teacher.m

#import "Teacher.h"

@implementation Teacher
- (instancetype)initWithName:(NSString *)name andID:(long)ID andSubject:(NSString *)subject
{
    self = [super init];
    self=[super initWithName:name andID:ID];
    
    if (self) {
        _subject=subject;
    }
    return self;
}
@end

Student.h

#import "Person.h"

@interface Student : Person

@end

Student.m

#import "Student.h"

@implementation Student
//4.移除观察者（监听者）
-(void)dealloc{
    [[NSNotificationCenter defaultCenter]removeObserver:self];

}
-(void)saySomething{
    NSLog(@"完了");
}
@end

Parent.h

#import "Person.h"

@interface Parent : Person

@end

Parent.m

#import "Parent.h"

@implementation Parent
//4.移除观察者（监听者）
-(void)dealloc{
    [[NSNotificationCenter defaultCenter]removeObserver:self];
    
}
-(void)saySomething{
    NSLog(@"加油");
}
@end

main.m

#import <Foundation/Foundation.h>
#import "Teacher.h"
#import "Student.h"
#import "Parent.h"
#import "Person.h"
int main(int argc, const char * argv[]) {
    @autoreleasepool {

        Teacher*teacher=[[Teacher alloc]initWithName:@"王老师" andID:@"1101" andSubject:@"ios"];
        Student*student=[[Student alloc]initWithName:@"李明" andID:@"1201"];
        Parent*parent=[[Parent alloc]initWithName:@"李明博" andID:@"1301"];
        [student addObserver];
        [parent addObserver];
        [teacher postNotification];
        
        
    }
    return 0;
}

 输出结果

2015-08-18 17:30:04.971 NSNoticafiction[2825:103009] {

    "class Meeting" = kaoshi;

    date = "8-20";

}

2015-08-18 17:30:04.972 NSNoticafiction[2825:103009] 完了

2015-08-18 17:30:04.972 NSNoticafiction[2825:103009] {

    "class Meeting" = kaoshi;

    date = "8-20";

}

2015-08-18 17:30:04.972 NSNoticafiction[2825:103009] 加油