iOS寻找当前View的控制器

分类方法

• (UIViewController )findViewController
  {
  for (UIView next = self; next; next = next.superview) {
  UIResponder* nextResponder = [next nextResponder];
  if ([nextResponder isKindOfClass:[UIViewController class]]) {
  return (UIViewController*)nextResponder;
  }
  }
  return nil;
  }