如何在導航欄內添加頁面指示器？

Question

像Twitter那樣：

我有一個的UITabBarController內PageViewController這又是一個UINavigationController內。

誰能告訴我如何在導航欄內顯示頁面指示器？

Answer 1

編輯：我只是想出了navigationController.viewControllers只包含堆棧。 我會在一分鐘後發佈編輯

編輯2：好吧，看來你必須事先知道視圖控制器的數量。

也許不是最好的解決方案，但它適用於我。剛剛嘗試:)

@interface ViewController() <UINavigationControllerDelegate> 
@property (nonatomic, strong) UIPageControl *pageControl; 
@end 

@implementation ViewController 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    UINavigationController *navController = self.navigationController; 
    navController.delegate = self; 

    navController.navigationBar.barTintColor = [UIColor colorWithRed:.2 
                   green:.4 
                   blue:.9 
                   alpha:1]; 

    CGSize navBarSize = navController.navigationBar.bounds.size; 
    CGPoint origin = CGPointMake(navBarSize.width/2, navBarSize.height/2); 

    self.pageControl = [[UIPageControl alloc] initWithFrame:CGRectMake(origin.x, origin.y, 
                     0, 0)]; 

    //Or whatever number of viewcontrollers you have 
    [self.pageControl setNumberOfPages:2]; 

    [navController.navigationBar addSubview:self.pageControl]; 

    navController.delegate = self; 
} 

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated 
{ 
    int index = [navigationController.viewControllers indexOfObject:viewController]; 
    self.pageControl.currentPage = index; 
} 

@end 

這裏是一些截圖。