iOS block

 

定义：

returnType (^funcName)(paramType paraName) = ^(paramType paraName){};

 

 

作为方法参数时：

- (void)fun:( returnType (^funcName)(paramType paraName) ) blockName{}

 

 

typedef:

typedef returnType (^funcName)(paramType paraName);

 

 

防止block发生循环引用：

__weak __typeof(self) weakSelf = self;

AController *vc = [[AController alloc] initWithCallback:^{

    [weakSelf.button setTitleColor:[UIColor greenColor] forState:UIControlStateNormal];

  }];