先自定義一個UITabbarController，用於Storyboard中

再在MyTabbarController中實現protocol

@interface MyTabbarController : UITabBarController <UITabBarControllerDelegate>

@end

@implementation MyTabbarController

- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController {
    NSLog(@"shouldSelectViewController  %@", tabBarController.selectedViewController);
    if (viewController.tabBarItem.tag == 100) {
        DiaryViewController *vc = [self.storyboard instantiateViewControllerWithIdentifier:DIARY_VC_ID];
        [((UINavigationController *)tabBarController.selectedViewController) pushViewController:vc animated:YES];
        return NO;
    }
    return YES;
}

- (id)initWithCoder:(NSCoder *)aDecoder {
    self = [super initWithCoder:aDecoder];
    if (self) {
        self.delegate = self;
    }
    return self;
}
@end
 

則找到該tabbar，我的是父控制元件的tabbar，所以

- (void)viewWillAppear:(BOOL)animated {
    self.parentViewController.tabBarController.tabBar.hidden = YES;
}

- (void)viewWillDisappear:(BOOL)animated {
    self.parentViewController.tabBarController.tabBar.hidden = NO;    
}
 

點選以上圖片中的“日記”時，則