过渡到其他collectionviewController时collectionviewCell不会改变

Posted 2023-03-14

【中文标题】过渡到其他collectionviewController时collectionviewCell不会改变

【英文标题】：collectionviewCell not change when transition to other collectionviewController

【发布时间】：2013-10-30 08:37:41

【问题描述】：

我创建了 2 个 UICollectionView 类，每个类使用 2 个不同的 UICollectionViewCell

@interface PhotosCollectionViewController : UICollectionViewController
@interface FullScreenCollectionViewController : UICollectionViewController

@interface PhotoCell : UICollectionViewCell
@interface FullPhotoCell : UICollectionViewCell<UIScrollViewDelegate>

在PhotosCollectionViewController.m中，我注册了PhotoCell类并在didSelect时选择下一个视图控制器是FullScreenCollectionViewController

//Register Cell
-(id)initWithCollectionViewLayout:(UICollectionViewFlowLayout *)layout
    if (self = [super initWithCollectionViewLayout:layout])
            
        [self.collectionView registerClass:[PhotoCell class] forCellWithReuseIdentifier:CELL_ID];
    
    return self;

//dequence resuse code
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath

    PhotoCell* cell = (PhotoCell *)[collectionView dequeueReusableCellWithReuseIdentifier:CELL_ID forIndexPath:indexPath];
    NSLog(@"reuse CELL");
    FICDPhoto *photo = [_photos objectAtIndex:indexPath.row];
    cell.imageView.image = [photo sourceImage];
    return cell;

//Next ViewController transition code
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath

    UIViewController *vc = [self nextViewControllerAtPoint:CGPointZero];
    [self.navigationController pushViewController:vc animated:YES];



-(UICollectionViewController*)nextViewControllerAtPoint:(CGPoint)p

    FullScreenCollectionViewController* nextCollectionViewController = [[FullScreenCollectionViewController alloc] initWithCollectionViewLayout:[[FullScreenFlowLayout alloc] init]];

    nextCollectionViewController.useLayoutToLayoutNavigationTransitions = YES;

    nextCollectionViewController.title = @"FullScreen";
    return nextCollectionViewController;

在FullScreenCollectionViewController中，我注册了FullPhotoCell类

[self.collectionView registerClass:[FullPhotoCell class] forCellWithReuseIdentifier:CELL_ID_FULL];

但序列码从不调用

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath

    FullPhotoCell* cell = (FullPhotoCell *)[collectionView dequeueReusableCellWithReuseIdentifier:CELL_ID_FULL forIndexPath:indexPath];
    NSLog(@"Reuse FULL Cell");
    FICDPhoto *photo = [_photos objectAtIndex:indexPath.row];
    cell.imageView.image = [photo sourceImage];
    return cell;

应用新布局，FullScreenCollectionViewController 的 viewDidload 也被调用，但日志消息“reuse CELL”告诉 fullScreen CollectionView 仍然使用旧的 PhotoCell 类。

我还是不明白有什么问题。请帮帮我！

【参考方案1】：

答案“有点”晚了，但这可能对其他人有用。当您使用useLayoutToLayoutNavigationTransitions 时，来自视图控制器的集合视图启动转换实际上被重用。此集合视图具有不同的数据源和委托，这就是为什么不调用 FullScreenCollectionViewController 的 cellForRowAtIndexPath 的原因。看看这个类似的问题： UICollectionView UseLayoutToLayoutNavigationTransitions with different datasources