UICollectionViewCell does not take maximum width

Question

I'm trying to make cells take as much width as possible, but I end up like this:

I have tried to remove margins, line spacing etc. in xcode:

But the horizontal margin is still huge, I want the same vertical margin applied.

Any ideas?

P.S attached example code:

- (void)viewDidLoad {
    [super viewDidLoad];
    self.collectionView.delegate = self;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
    return 9;
}

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView
{
    return 1;
}

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

    CollectionCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];

    cell.backgroundColor = [UIColor whiteColor];
    return cell;
}

Answer 1

You set the Collection cell to be 100x100, and to be 3 at row.

So the UICollectionView is minimum 300/300. If you make the view to be 320(normal iPhone width), then the Collection View set padding between the cells automatically.

EDIT:

Try:

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

    CollectionCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];

    cell.backgroundColor = [UIColor whiteColor];

    //3 because you wanted 3 cells. 18 is the min padding between the cell.
    cell.frame.size.width = collectionView.frame.size.width/3-18;

    return cell;
}