Question

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];

但序列码永远不会调用

- (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;
}

新布局适用，FullScreenCollectionViewController的viewDidload也调用，但日志消息“重用CELL”告诉fullScreen CollectionView仍然使用旧的PhotoCell类。

我仍然不明白什么是问题。请帮帮我！

Answer 1

答案是＆＃34;有点＆＃34;迟到但这可能对其他人有用。当您使用useLayoutToLayoutNavigationTransitions视图控制器中的集合视图时，实际上会重用过渡。此集合视图具有不同的数据源和委托，这就是为什么FullScreenCollectionViewController cellForRowAtIndexPath未被调用的原因。看看这个类似的问题： UICollectionView UseLayoutToLayoutNavigationTransitions with different datasources

转换到其他collectionviewController时，collectionviewCell不会更改

1 个答案: