类目：nextResponder

#import "UIView+ViewController.h"

@implementation UIView (ViewController)

- (UIViewController *)viewController
{
    id next = [self nextResponder];
    while (next != nil) {

        if ([next isKindOfClass:[UIViewController class]]) {
            UIViewController *viewCtrl = next;
            return viewCtrl;
        }

        next = [next nextResponder];
    }
    return nil;
}

@end