UITabbarController仅显示第一个选项卡

Question

我在故事板中手动添加了UITabbarController，而不是根视图控制器。我添加了tabbar项目并设置了segue关系。当UITabbarController的第一个视图控制器即将呈现时，我还在代码中设置每个tabbar项的图像和标题，但无论我做什么，只有第一个项的图像是可见的。其他项目图像只有在被点击并且实际加载了它们的视图时才可见。任何输入如何解决它？

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.

if ([segue.identifier isEqualToString:@"AfterLogin"]) {

    UITabBarController *tabBarController = [segue destinationViewController];
    NSArray *tabBarItems = tabBarController.tabBar.items;

    UITabBarItem *item1 = tabBarItems[0];
    UITabBarItem *item2 = tabBarItems[1];
    UITabBarItem *item3 = tabBarItems[2];
    UITabBarItem *item4 = tabBarItems[3];

    [item1 setImage:[[UIImage imageNamed:@"image1_static"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    [item1 setSelectedImage:[[UIImage imageNamed:@"image1_active"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    item1 = @"";
    item1.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0);

    [item2 setImage:[[UIImage imageNamed:@"image2_static"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    [item2 setSelectedImage:[[UIImage imageNamed:@"image1_active"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    item2.title = @"";
    item2.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0);

    [item3 setImage:[[UIImage imageNamed:@"image3_static"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    [item3 setSelectedImage:[[UIImage imageNamed:@"image3_active"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    item3.title = @"";
    item3.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0);

    [item4 setImage:[[UIImage imageNamed:@"image4_static"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    [item4 setSelectedImage:[[UIImage imageNamed:@"image4_active"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
    item4.title = @"";
    item4.imageInsets = UIEdgeInsetsMake(6, 0, -6, 0);
}


}