1、UIViewController继承UITabbarcontroller
2、实现协议UITabBarControllerDelegate
3、设置协议

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    self.delegate = self;
}

4、实现协议方法

-(BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController{
    if (/*满足一个条件时，不跳转，返回NO*/) {
        return NO;
    }
    return YES;
}