UIPageViewController基本使用

UIPageViewController基本使用

@interface ViewController ()<UIPageViewControllerDelegate,UIPageViewControllerDataSource>

@property(nonatomic,strong)UIPageViewController *pageVC;
@property(nonatomic,strong)NSMutableArray *dataArr;
@end

@implementation ViewController

-(NSMutableArray *)dataArr{
    if(!_dataArr){
        _dataArr = [NSMutableArray array];
        [_dataArr addObject:[MyViewController new]];
        [_dataArr addObject:[MyViewController new]];
        [_dataArr addObject:[MyViewController new]];
    }
    return _dataArr;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.pageVC.view.bounds = CGRectMake(0, 0,SCREEN_WIDTH, SCREEN_HEIGHT);
    
}
-(UIPageViewController *)pageVC{
    if(!_pageVC){
        _pageVC = [[UIPageViewController alloc]initWithTransitionStyle:UIPageViewControllerTransitionStyleScroll navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:nil];
        _pageVC.delegate = self;
        
        _pageVC.dataSource = self;
        
        [self addChildViewController:_pageVC];
        [self.view addSubview:_pageVC.view];
        [_pageVC didMoveToParentViewController:self];
        [_pageVC setViewControllers:@[self.dataArr[0]] direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
    }
    return _pageVC;
}
#pragma mark UIPageViewControllerDelegate
- (void)pageViewController:(UIPageViewController *)pageViewController didFinishAnimating:(BOOL)finished previousViewControllers:(NSArray<UIViewController *> *)previousViewControllers transitionCompleted:(BOOL)completed{
   
}

#pragma mark UIPageViewControllerDataSource
- (nullable UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController{
    NSInteger currentPage = [self.dataArr indexOfObject:viewController];
    if(currentPage <= 0){
        return  nil;
    }else{
        currentPage --;
        return self.dataArr[currentPage];
    }
}
- (nullable UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController{
    NSInteger currentPage = [self.dataArr indexOfObject:viewController];

    if(currentPage >= self.dataArr.count - 1){
        return  nil;
    }else{
        currentPage ++;
        return self.dataArr[currentPage];
    }
}