key value observing

UIViewController.m 파일 안에서

// register observer

    void *context = (__bridge void *)self;

    [self.tableView addObserver:self

                     forKeyPath:@"contentOffset"

                        options:NSKeyValueObservingOptionNew

                        context:context];

#pragma mark - KVO Methods

- (void)observeValueForKeyPath:(NSString *)keyPath

                      ofObject:(id)object

                        change:(NSDictionary *)change

                       context:(void *)context

{

// Make sure we are observing this value.

if (context != (__bridge void *)self) {

[super observeValueForKeyPath:keyPath ofObject:object change:change context:context];

return;

}

    

    if ((object == self.tableView) &&

        ([keyPath isEqualToString:@"contentOffset"] == YES)) {

        [self scrollViewDidScrollWithOffset:self.tableView.contentOffset.y];

    }

}

- (void)scrollViewDidScrollWithOffset:(CGFloat)scrollOffset

{

     // do something

}

storyboard 밖에서 storyboard 리소스 호출하기.

MyController is in storyboard.

and

some place in a separate view controller :

  

MyController *controller =

    [[UIStoryboard storyboardWithName:@"Main_iPhone"

                               bundle:NULL] instantiateViewControllerWithIdentifier:@"MyViewController"];

    

[self.navigationController pushViewController:controller animated:YES];

xib 소스에서 storyboard 에 있는 viewcontroller 생성하기

OutUIViewController.xib
OutUIViewController.m
OutUIViewController.h


InUIViewController.m  InUIViewController.h   in Main_