How to remove spacing between lines in UICollectionView programmatically? - ios

Question

I have a UICollectionView and I can't get 0 spacing between lines. I have added UICollectionViewDelegateFlowLayout in .h class and implemented
(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section
and
(CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout
minimumInteritemSpacingForSectionAtIndex:(NSInteger)section**
methods set them to return 0.0. Also in ViewDidLoad I dynamically created UICollectionViewFlowLayout and UICollectionView. For UICollectionViewFlowLayout I set minimumInteritemSpacing and minimumLineSpacing to 0 but space between lines is still more than 0.
This is my code:
- (void)initializeCollectionView {
UICollectionViewFlowLayout* flowLayout = [[UICollectionViewFlowLayout alloc]init];
flowLayout.itemSize = CGSizeMake(50, 100);
[flowLayout setScrollDirection:UICollectionViewScrollDirectionHorizontal];
[flowLayout setMinimumLineSpacing:0.0];
flowLayout.minimumInteritemSpacing = 0;
flowLayout.minimumLineSpacing = 0;
collView = [[UICollectionView alloc] initWithFrame:CGRectMake(0, 50, self.view.frame.size.width, self.view.frame.size.height-70) collectionViewLayout:flowLayout];
[collView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:#"Cell"];
[collView setBackgroundColor:[UIColor grayColor]];
collView.delegate = self;
collView.dataSource = self;
[[self view] addSubview:collView];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
return 1;
}
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
return 100;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
return 0.0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout
minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 0.0;
}
- (UIEdgeInsets)collectionView:(UICollectionView*)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(0, 0, 0, 0);
}
Thank you for your answers.

Answer 1

I did it in a little different way. I created a collectionView programatically and added that to the view Controller. In my CollectionView Custom Class, I did all the customisation.
My Custom Collection View interface file-
#import <UIKit/UIKit.h>
#import "CustomCell.h"
#interface CustomCollectionView : UIView<UICollectionViewDelegateFlowLayout, UICollectionViewDataSource, UICollectionViewDelegate>
#property(nonatomic, strong) UICollectionView *myCollectionView;
#end
Now in the implementation File(CustomCollectionView.m), first I had to initialise and add my collectionView.
initWithFrame is called as soon as the view is drawn. So, I added my collectionView inside this view and let this view deal with all the delegate methods to customise my collection view and populate data through datasource methods.
-(id)initWithFrame:(CGRect)frame{
self=[super initWithFrame:frame];
if(self){
UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc]init];
flowLayout.scrollDirection = UICollectionViewScrollDirectionVertical;
self.myCollectionView = [[UICollectionView alloc]initWithFrame:CGRectMake(0, 20, frame.size.width, frame.size.height) collectionViewLayout:flowLayout];
self.myCollectionView.backgroundColor=[UIColor whiteColor];
self.myCollectionView.delegate=self;
self.myCollectionView.dataSource=self;
[self.myCollectionView registerClass:[CustomCell class] forCellWithReuseIdentifier:#"customCell"];
[self addSubview:self.myCollectionView];
}
return self;
}
Now, let's implememt the UICollectionViewDelegateFlowLayout methods
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
return 0;
}
- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
return 0;
}
- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
//here I just made sure that I have square spaces boxes as my cell size
int width = self.myCollectionView.frame.size.width/5;
int height = width;
return CGSizeMake(width, height);
}
Now the UICollectionView Datasource
- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section{
return 5;
}
- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView{
return 7;
}
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
CustomCell *cell =[collectionView dequeueReusableCellWithReuseIdentifier:#"customCell" forIndexPath:indexPath];
if(cell){
//customize the cell here
return cell;
}
}
Now when my custom view with collectionView is ready, I just added that to my viewController.
- (void)viewDidLoad {
[super viewDidLoad];
CustomCollectionView *myCollectionView = [[CustomCollectionView alloc]initWithFrame:CGRectMake(0, 10, self.view.frame.size.width, self.view.frame.size.height)];
[self.view addSubview: myCollectionView];
}
The above worked for me. You can do with storyboard to, but I found some complication when I tried to customise a collectionView connected by IBOutlet. So, I took this approach. There may be better ways to do that.