9.21 Block、协议、通知

Block

注: 将时机放到自己成员函数内部，防止出现循环引用

CustomView.h文件

@interface CustomView : UIView
- (void)demoFunc:(void(^)(void))handle;
@end

CustomView.m文件

@interface CustomView (){
void (^globalHandle)(void);
}
@end
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
  if(globalHandle){ 
  globalHandle(); 
}
}
- (void)demoFunc:(void (^)(void))handle{ 
  globalHandle = handle;
}

ViewController.h文件

CustomView *v = [[CustomView alloc]initWithFrame:CGRectMake(0, 0, 100, 100)];
v.center = self.view.center; [self.view addSubview:v]; 
v.backgroundColor = [UIColor redColor]; [v demoFunc:^{ 
NSLog(@"hello world"); 
}];

协议

Custom.h文件

@protocol CustomViewDelegate 
@optional- (void)messageSend;
@end@property(nonatomic,weak)id delegate;

Custom.m文件

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{ 
if([self.delegate respondsToSelector:@selector(messageSend)]){ 
[self.delegate messageSend]; 
}
}

ViewController.h文件

{ 
CustomView *v = [[CustomView alloc]initWithFrame:CGRectMake(0, 0, 100, 100)]; 
v.center = self.view.center; 
[self.view addSubview:v]; 
v.backgroundColor = [UIColor redColor];
v.delegate = self;
}
- (void)messageSend{ NSLog(@"hello world_delegate");
}

通知

注: 通知一般用于一对多，当"1"里面的代码比较多的时候，会影响"2"后面代码的执行,key比较难管理。而且一旦某个过程慢了半拍，或者出现卡顿时，其他函数也会被影响。

Custom.m文件

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
[[NSNotificationCenter defaultCenter]postNotificationName:@"kClicked" object:nil]; 
}//"2"

ViewController

{ 
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(notiHandle:) name:@"kClicked" object:nil];
}
- (void)notiHandle:(NSNotification*)noti{ 
// "1" NSLog(@"hello world_noti");
}