iOS - 从 plist 数据滚动图像

Question

我用UICollectionView 创建了一个图库，并从 plist 文件加载一组图像，当用户触摸每个单元格时，将加载一个全屏图像（与 iPhone 的照片应用程序相同），所以我遇到了问题是当照片全屏时我无法滚动和查看其他图像，这是我的代码：

然后在 PhotosViewerController 中：

-(void) creatContentWithNumerOfPage: (NSInteger) numberOfPage andCurrentPage: (NSInteger) currentPage andImageArray:(NSArray *)imageArray {

    self.pageControl.numberOfPages = numberOfPage;
    self.pageControl.currentPage = currentPage;
    [pageScrollView setContentSize:CGSizeMake(self.view.frame.size.width * pageControl.numberOfPages, self.view.frame.size.height)];
    pageScrollView.delegate = self;
    [self.view addSubview: pageScrollView];


    NSMutableArray *mArray = [[NSMutableArray alloc] initWithCapacity:thumbnailViewController.imageArray.count];
    for (int i = 0; i <= thumbnailViewController.imageArray.count; i++)
    {

        NSDictionary *picturesDictionary = [NSDictionary dictionaryWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"Photos" ofType:@"plist"]];
        imageArray = [picturesDictionary objectForKey:@"PhotosArray"];

        fullScreen = [[UIImageView alloc]initWithImage:[UIImage imageNamed:[imageArray objectAtIndex:currentPage]]];
        [fullScreen setContentMode:UIViewContentModeScaleAspectFit];
        fullScreen.frame = self.view.frame;

        [mArray addObject:fullScreen];
        [pageScrollView addSubview:fullScreen];
    }

}

已编辑：（解决方案）

-(void) creatContentWithImages:(NSArray*)imageArray andCurrentPage:(NSInteger)currentPage{

    self.pageControl.numberOfPages = imageArray.count;
    self.pageControl.currentPage = currentPage;
    [self.pageScrollView setContentSize:CGSizeMake(self.pageScrollView.frame.size.width * imageArray.count, self.pageScrollView.frame.size.height)];


    for (int i = 0; i < imageArray.count; i++)
    {


        NSDictionary *picturesDictionary = [NSDictionary dictionaryWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"Photos" ofType:@"plist"]];
        imageArray = [picturesDictionary objectForKey:@"PhotosArray"];

        fullScreen = [[UIImageView alloc]initWithImage:[UIImage imageNamed:[imageArray objectAtIndex:i]]];


        [fullScreen setContentMode:UIViewContentModeScaleAspectFit];
        fullScreen.frame = CGRectMake(i*self.pageScrollView.frame.size.width, 0, self.pageScrollView.frame.size.width, self.pageScrollView.frame.size.height);

        [self.pageScrollView addSubview:fullScreen];
    }

    [self scrollToPage:currentPage animated:NO];

}

Answer 1

你的代码有很多问题，例如

• 您调用creatContentWithImages 之前 viewDidLoad 方法并在此 点我们不能指望self.view.frame 的实际值或 self.pageScrollView.frame，您必须在viewDidLoad 中/之后调用它。 可能是这样的：

  [self presentViewController:photosViewController animated:YES completion:^{
      [photoViewController creatContentWithImages:images andCurrentPage:row];
  }];
  

• 在循环中你总是使用currentPage 而不是i ivar

• 您将imageArray 发送到creatContentWithNumerOfPage 方法中，但是
  由于某种原因，这个数组在这里被新数据覆盖（I
  假设使用相同的数据）
• 还不清楚您为什么执行[self.view addSubview:
pageScrollView] - UIScrollView 是通过编程方式创建的吗？但它发生在哪个地方？
• 当您使用框架进行操作时，您应该使用 UIScrollView 框架， 不是 UIView，如果您的滚动大小与 UIView 不同，那么
  设计也会被破坏。

我已经更改并改进了一些东西，所以让我们看看这个（我发布了所有整个 PhotosViewerController.m 文件）

#import "PhotosViewerController.h"
@implementation PhotosViewerController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

-(void) creatContentWithImages:(NSArray*)imageArray andCurrentPage:(NSInteger)currentPage{
// I create UIScrollView programmatically, if you want to use xib then just remove lines with RM comment. 
// There are two views in xib hierarchy - UIScrollView downward and UIPageView above

    self.pageScrollView = [[UIScrollView alloc] initWithFrame:self.view.frame]; //RM
    self.pageScrollView.pagingEnabled = YES; //RM

    self.pageControl.numberOfPages = imageArray.count;
    self.pageControl.currentPage = currentPage;
    [self.pageScrollView setContentSize:CGSizeMake(self.pageScrollView.frame.size.width * imageArray.count, self.pageScrollView.frame.size.height)];

    self.pageScrollView.delegate = self;//RM
    [self.view insertSubview:self.pageScrollView atIndex:0]; //RM

    for (int i = 0; i < imageArray.count; i++) //not <=, just <
    {
        UIImage *img = [imageArray objectAtIndex:i];// not sure whether imageArray contains UIImage's or NSString, so if here NSString the create UIImage in appropriate manner. I've tested it with UIImage's 
        UIImageView *fullScreen = [[UIImageView alloc] initWithImage:img];
        [fullScreen setContentMode:UIViewContentModeScaleAspectFit];
        fullScreen.frame = CGRectMake(i*self.pageScrollView.frame.size.width, 0, self.pageScrollView.frame.size.width, self.pageScrollView.frame.size.height);

        [self.pageScrollView addSubview:fullScreen];
    }

    [self scrollToPage:currentPage animated:NO]; // scroll to corresponding page
}

- (void)scrollViewDidScroll: (UIScrollView *) sView
{
    CGFloat offset = self.pageScrollView.contentOffset.x;
    CGFloat pageSize = self.pageScrollView.frame.size.width;

    int page = floor((offset + (pageSize/2)) / pageSize);
    self.pageControl.currentPage = page;
}

- (IBAction)changeThePage:(id)sender
{
    NSLog(@"Change");
    [self scrollToPage:self.pageControl.currentPage animated:YES];
}

- (void)scrollToPage:(NSInteger)page animated:(BOOL)animated{
    CGRect pageRect = CGRectMake(page * self.pageScrollView.frame.size.width, 0, self.pageScrollView.frame.size.width, self.pageScrollView.frame.size.height);    
    [self.pageScrollView scrollRectToVisible: pageRect animated: animated];

    [self.pageControl setCurrentPage:page];
}
@end

如果您还有任何问题，请告诉我，我会尽力帮助您。