Question

On certain events,

I’d like to remove all cells in a uicollectionview, and add new cells.(which will be populated as a result of a network call)

I tried using deleteItemsAtIndexPaths.
reloadSections, deleteSections/insertSections.

Each of them crashed my app.

Below is my code.

NSMutableArray* indexPathArray = [[NSMutableArray alloc] init];

for(int i=0; i < [self.jsonAlbumImageArray count]; ++i)
{
    NSIndexPath* newPath = [NSIndexPath indexPathForRow:i inSection:0];
    [indexPathArray addObject: newPath];
}

[self.jsonAlbumImageArray removeAllObjects];

if(indexPathArray.count > 0 )
{
    [self.collectionView performBatchUpdates:^{
            [self.collectionView deleteItemsAtIndexPaths:indexPathArray];
        }
    completion: nil];
}

// NSIndexSet *indexSet = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, 1)];                                                                                                                                                                                        
// NSIndexSet* indexSet = [NSIndexSet indexSetWithIndex:0];                                                                                                                                                                                                                 
// [self.collectionView reloadSections:indexSet];                                                                                                                                                                                                                           

[self get_IMAGE_LIST_FROM_SERVER];

Answer 1

Yeah, as Jonathan said, I think what you want to do is change your datasource with the new data and simply “refresh” or reload the UICollectionView.