-viewWillAppear in iOS 7.0

- (void) viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];

    const BOOL isInteractivePop = (self.navigationController.interactivePopGestureRecognizer.state == UIGestureRecognizerStateBegan);

    if(isInteractivePop)
    {
        //    Interactive pop stuff
    }
    else
    {
        //    Back button stuff
    }
}