I am trying to create a nested collection view. First I did for one level.
Created a data model class with String header. In app delegate created an array sectionTitle. Now in the nib, I added collection view & array controller and did all the bindings following this guide. Next in awakeFromNib I populated some random data
- (void)awakeFromNib {
int idx = 0;
NSMutableArray *sectionTitle = [[NSMutableArray alloc] init];
while (idx < 1) {
HeaderModel *header = [[HeaderModel alloc] init];
[header setHeader:[NSString stringWithFormat:@"Section %d", idx]];
[sectionTitle addObject:header];
idx++;
}
[self setHeaderData:sectionTitle];
}
Running it will give me 4 sections. I want to achieve similar layout as this. Section title, under it another collection of items. The answer given there only hints at using Nested collection view.
So I added another collection view in the first view prototype. Then I followed the same approach what I did for the first view(with different data model and array).
- (void)awakeFromNib {
int idx = 0;
NSMutableArray *sectionTitle = [[NSMutableArray alloc] init];
NSMutableArray *groupData = [[NSMutableArray alloc] init];
while (idx < 1) {
HeaderModel *header = [[HeaderModel alloc] init];
DataModel *name = [[DataModel alloc] init];
[header setHeader:[NSString stringWithFormat:@"Section %d", idx]];
[name setName:[NSString stringWithFormat:@"Name %d", idx]];
[sectionTitle addObject:header];
[groupData addObject:name];
idx++;
}
[self setHeaderData:sectionTitle];
[self setData:groupData]; //NSCollectionView item prototype must not be nil.
}
But now I get the error NSCollectionView item prototype must not be nil. How do I resolve this ?
