iOS - 通过view查找所在(viewController)

- (UIViewController *)findViewController:(UIView *)sourceView
{
 
        id target=sourceView; 
 
        while (target) {
 
           target = ((UIResponder *)target).nextResponder;
 
           if ([target isKindOfClass:[UIViewController class]]) {
 
               break;
       }
   }
 
   return target;
}