UIPageViewController的NavigationBar不显示标题

Question

UIPageViewController的导航栏未显示页码作为导航栏的标题。

- (void)viewDidLoad {

[super viewDidLoad];

//modelArray holds the page numbers
modelArray = [[NSMutableArray alloc] init];

for (int index = 1; index <= totalPages; index++) {

    [modelArray addObject:[NSString stringWithFormat:@"%i", index]];

}

UINavigationBar *navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, 45)];

navBar.tintColor = [UIColor colorWithRed:243.0/255.0 green:164.0/255.0 blue:0.0/255.0 alpha:1.0];

self.navigationItem.title = modelArray;

[self displayPageNumber:1];

thePageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl navigationOrientation: UIPageViewControllerNavigationOrientationHorizontal options:nil];

thePageViewController.delegate = self;
thePageViewController.dataSource = self;

thePageViewController.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

contentViewController = [[ContentViewController alloc] initWithPDF:PDFDocument];
contentViewController.page = [modelArray objectAtIndex:0];
NSArray *viewControllers = [NSArray arrayWithObject:contentViewController];
[thePageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];

[self addChildViewController:thePageViewController];
[self.view addSubview:thePageViewController.view];
thePageViewController.view.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);


[thePageViewController didMoveToParentViewController:self];

_toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 960, self.view.bounds.size.width, 45)];

_toolbar.barStyle = UIBarStyleBlackOpaque;

_toolbar.tintColor = [UIColor colorWithRed:243.0/255.0 green:164.0/255.0 blue:0.0/255.0 alpha:1.0];

 [self.view addSubview:_toolbar];

[self.view addSubview:navBar];
 }

  - (void) pageViewController:(PageViewController *)pageViewController willTurnToPageAtIndex:(NSUInteger)pageIndex {
[self displayPageNumber:pageIndex + 1];
}


   - (void) displayPageNumber:(NSUInteger)pageNumber {
self.navigationItem.title = [NSString stringWithFormat:
                             @"Page %u of %u",
                             pageNumber,
                             CGPDFDocumentGetNumberOfPages(PDFDocument)];
     }

感谢帮助。

Answer 1

这可能是因为您创建了navBar，将其添加到子视图，但更改了self.navigationItem 。 正如我在您的代码中看到的，这些是不同的导航栏。 尝试将navBar保存到某个strong属性并更改navBar而不是self.navigationItem

PS在这一行中self.navigationItem.title = modelArray; 您为NSString分配NSMutableArray。 那很糟 ：）

Answer 2

如果你只看到橙色的navBar ，那么你的self.navigationItem就不显示了。 你需要你的viewController是navigationController的孩子，就像那样：

如果你这样做，那么你可以写self.navigationItem.title = @"123"; 像这儿：

你会得到你想要的结果：

UPD：或者你可以这样做：

@interface MCViewController ()

@property (strong, nonatomic) UINavigationItem *navItem;
@property (strong, nonatomic) UINavigationBar *navBar;

@end

@implementation MCViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.navItem = [[UINavigationItem alloc] initWithTitle:@"TEST"];
    self.navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
    self.navBar.items = @[self.navItem];
    [self.view addSubview:self.navBar];
}

@end

然后改变navItem title属性。

Answer 3

很简单。

这样做吧

_navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, 45)];

_navBar.tintColor = [UIColor colorWithRed:243.0/255.0 green:164.0/255.0 blue:0.0/255.0 alpha:1.0];

UINavigationItem *title = [[UINavigationItem alloc] initWithTitle:[NSString stringWithFormat:
                                                                   @"Page %i of %i",
                                                                   pageNumber,
                                                                   CGPDFDocumentGetNumberOfPages(thePDF)]];
[_navBar pushNavigationItem:title animated:NO];

希望它能帮到你。