我一直试图绕过UICollectionView的reloadItemsAtIndexPaths方法.
我有一个名为objectsArray的对象数组.当用户滚动到我的集合视图的底部时,我从后端获取下一批对象,并通过调用[objectsArray addObjectsFromArray：objects]将其附加到objectsArray;这样做后,我调用[self.collectionView reloadData],我知道这是昂贵的.
我想用下面的代码进行优化,但是在调用reloadItemsAtIndexPaths时我得到一个断言失败.
if (self.searchPage == 0) {
parSEObjectsArray = [[NSMutableArray alloc] initWithArray:relevantDeals];
[self.collectionView reloadData];
} else {
NSMutableArray *indexPaths = [[NSMutableArray alloc] init];
for (int i = 0; i < [relevantDeals count]; i++) {
NSIndexPath *indexPath = [NSIndexPath indexPathForItem:i inSection:0];
[indexPaths addObject:indexPath];
}
[parSEObjectsArray addObjectsFromArray:relevantDeals];
[self.collectionView reloadItemsAtIndexPaths:indexPaths];
//[self.collectionView reloadData];
}
错误：
*断言失败 – [UICollectionView _endItemAnimations],/ SourceCache / UIKit / UIKit-2903.2 / UICollectionView.m：3716
非常感谢任何帮助/提示.
谢谢！
解决方法
看起来添加的项目是新的,换句话说,您正在添加以前不存在的项目.在这种情况下,只需用insertItemsAtIndexPaths替换reloadItemsAtIndexPaths：indexPaths：
[self.collectionView insertItemsAtIndexPaths:indexPaths]; // Use this for newly added rows //[self.collectionView reloadItemsAtIndexPaths:indexPaths]; // Use this for existing rows which have changed