ios - 如何在 objective-c 中的其他 View Controller 中隐藏按钮

Question

-(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {
    NewsScreen *news=[[NewsScreen alloc] initWithNibName:@"NewsScreen" bundle:nil];

    if (tabBarController.selectedIndex==2) {

        [news.btn setHidden: YES];

    }
    NSLog(@"%@", tabBarController);
}

我想隐藏来自另一个 View Controller 的按钮。

Answer 1

    -(void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {

            if (tabBarController.selectedIndex==2) 
            {
              NSUInteger *index=value; //assign value here
              UINavigationController *nv = [[tabBarController viewControllers] objectAtIndex:index];//index of your NewsScreen controller
              NSArray *array =[nv viewControllers];

              for (ViewController *vc in array)
              {
                if ([vc isKindOfClass:[NewScreen class]])
                {
                  [vc.btn setHidden:YES];
                }
              }

            }
            NSLog(@"%@", tabBarController);
        }