navigationbar上拉隐藏

navigationbar.m

- (void)p_setNavBarHidden:(BOOL)hidden {
    if (hidden) {
        [[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationFade];
        [UIView animateWithDuration:0.5 animations:^{
            [self.navigationController.navigationBar setY:- HEIGHT_NAVBAR - HEIGHT_STATUSBAR];
        } completion:^(BOOL finished) {
            [self.navigationController.navigationBar setHidden:YES];
        }];
    }
    else {
        [self.navigationController.navigationBar setHidden:NO];
        [[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];
        [UIView animateWithDuration:0.2 animations:^{
            [self.navigationController.navigationBar setY:HEIGHT_STATUSBAR];
        }];
    }
}