IOS - UIPageViewController使用卷页效果转到前一页，并在每页上显示页码

Question

我是第一次使用UIPageViewController，

我想使应用程序，向左和向右滑动相同的看法。我只使用了一个uitableview来无限滑动uipageviewcontroller。

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使用滚动效果可以很好地工作，但是当我使用页面卷曲效果时，它只允许向右滑动，不能转到上一页。

以下是我的PageViewController文件代码：

- (void)viewDidLoad {
    [super viewDidLoad];
    self.dataSource = self;
    self.delegate = self;
    [self didMoveToParentViewController:self];
    _counter = 0;

    [self setViewControllers:@[[self.storyboard instantiateViewControllerWithIdentifier:@"memoTable"]] direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];

    // Do any additional setup after loading the view.
}

- (BOOL)prefersStatusBarHidden {
    return YES;
}

#pragma mark PageViewController delegate method

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    NSLog(@"Child controller counter before  = %d", _counter);

    if ([viewController isKindOfClass:[PageController class]])
        return nil;

    if(_counter < 1) {
        return nil;
    }

    self.view.backgroundColor = [UIColor lightGrayColor];
    return [self.storyboard instantiateViewControllerWithIdentifier:@"memoTable"];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
    NSLog(@"Child controller counter after  = %d", _counter);
    if ([viewController isKindOfClass:[PageController class]])
        return nil;
    return [self.storyboard instantiateViewControllerWithIdentifier:@"pageView"];
}

那么如何使用页面卷曲效果和左右滑动来实现这一点呢？

谢谢。

Answer 1

因为你需要的是单边无穷大，你需要检查你的index，如果它是0而不是return nil。

PageViewController**:**的一些检查方法

// Create the data model.
        NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
        _pageData = [[dateFormatter monthSymbols] copy];

- (DataViewController *)viewControllerAtIndex:(NSUInteger)index storyboard:(UIStoryboard *)storyboard {
    // Return the data view controller for the given index.
    if (([self.pageData count] == 0) || (index >= [self.pageData count])) {
        return nil;
    }

    // Create a new view controller and pass suitable data.
    DataViewController *dataViewController = [storyboard instantiateViewControllerWithIdentifier:@"DataViewController"];
    dataViewController.dataObject = self.pageData[index];
    return dataViewController;
}

- (NSUInteger)indexOfViewController:(DataViewController *)viewController {
    // Return the index of the given data view controller.
    // For simplicity, this implementation uses a static array of model objects and the view controller stores the model object; you can therefore use the model object to identify the index.
    return [self.pageData indexOfObject:viewController.dataObject];
}

#pragma mark - Page View Controller Data Source

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    NSUInteger index = [self indexOfViewController:(DataViewController *)viewController];
    if ((index == 0) || (index == NSNotFound)) {
        return nil;
    }

    index--;
    return [self viewControllerAtIndex:index storyboard:viewController.storyboard];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
    NSUInteger index = [self indexOfViewController:(DataViewController *)viewController];
    if (index == NSNotFound) {
        return nil;
    }

    index++;
    if (index == [self.pageData count]) {
        return nil;
    }
    return [self viewControllerAtIndex:index storyboard:viewController.storyboard];
}

你必须管理一个数组，才能识别index | count中的每一件事。

在上面的例子中，self.pageData是我用来管理页面的数组。如果你需要任何帮助，请告诉我。