UICollectionView - Where to design each cell. Frames given doesnt work properly - ios

Question

I want to create 3 cells in each row, with width & height 104.0f each. But I am getting the output as shown in the screenshot.
The code used is given below. Since I am new to UICollectionView, I have no idea how to implement this. Where do I design the cells incase if frames are different for all?
- (void)viewDidLoad
{
....
UICollectionViewFlowLayout *layout=[[UICollectionViewFlowLayout alloc] init];
dealListCollectionView=[[UICollectionView alloc] initWithFrame:CGRectMake(1.0f, 1.0f, 320.0f, 525.0f) collectionViewLayout:layout];
[dealListCollectionView setDataSource:self];
[dealListCollectionView setDelegate:self];
[dealListCollectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:#"cellIdentifier"];
[dealListCollectionView setBackgroundColor:[UIColor lightGrayColor]];
[self.view addSubview:dealListCollectionView];
}
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section
{
return 10;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
UICollectionViewCell *cell=[collectionView dequeueReusableCellWithReuseIdentifier:#"cellIdentifier" forIndexPath:indexPath];
cell.backgroundColor=[UIColor greenColor];
return cell;
}
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
return CGSizeMake(104, 104);
}
- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(0, 0, 0, 0);
}
- (UIEdgeInsets)insetsForItemAtIndexPath:(NSIndexPath *)indexPath {
return UIEdgeInsetsMake(2, 2, 2, 2);
}

Answer 1

Click on your CollectionView, Go to the Size Inspector and change the default value of Min Spacing For Cells and For Rows. For your size 104x104 it have to be 4px.

Answer 2

The below code solved my problem :
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 2.0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
return 2.0;
}