Working with collectionView and collectionViewCells

Question

It's the first time i'm working with UICollectionView and UICollectionViewCells. I am trying to make a simple view. The problems i' facing are: reloading collection view data, displaying text (from array) into cell labels.. code is here.. please help as much as you can.. <3 (app crashes when i don't add subview)

  #import "MainCollectionViewController.h"
#import "MainCollectionViewCell.h"


@interface MainCollectionViewController () <UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout>

{
    UICollectionView *colView;
}
@end

@implementation MainCollectionViewController

static NSString * const reuseIdentifier = @"Cell";

- (void)viewDidLoad {
    [super viewDidLoad];


 //  [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];


    self.actressArray = [NSMutableArray arrayWithObjects:@"John", @"Patrick", @"Jack", @"Clara", @"Nicol", @"Amanda", @"Nick", @"Bob", @"Jeff", @"Jerremy", @"Gloria", @"Bred", @"Seth", @"Peter", @"Lous", nil];



    self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    UICollectionViewFlowLayout *layout=[[UICollectionViewFlowLayout alloc] init];
    colView=[[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:layout];
    [colView setDataSource:self]; //დელეგატების კოდით ჩართვა
    [colView setDelegate:self];

    [colView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];
    [colView setBackgroundColor:[UIColor grayColor]]; //ვიუს ბექგრაუნდის ფერი

    UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
    [flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];
    [self.collectionView setCollectionViewLayout:flowLayout];

    [self.view addSubview:colView]; //ვიუზე ჩვენ მიერ გამზადებული ვიუს დაგდება

    [self.collectionView registerClass:[MainCollectionViewCell class] forCellWithReuseIdentifier: reuseIdentifier];


    ////[self.collectionView reloadData];
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}




//// In a storyboard-based application, you will often want to do a little preparation before navigation
//- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender //{
//}




- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {

    return _actressArray.count;
}


- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {


    return 3;
}

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

    MainCollectionViewCell *cell = (MainCollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:reuseIdentifier forIndexPath:indexPath];



    NSString *actressStr = [_actressArray objectAtIndex:indexPath.row];
    cell.actressLabel.text = actressStr;

    //[self.collectionView reloadData];

    //[cell.contentView addSubview:  ];



    return cell;
}

score 0 · Answer 1 · answered Apr 02 '16 at 13:48

0

1 Please Check You Outlets Connection Once again :-

2 And What's Error ???

answered Apr 02 '16 at 13:48

Rahul Sharma

264
1
17

i have solved this problem, but forced new one. reload data not working – Marie Apr 02 '16 at 13:52
in cellForItemAtIndexPath there is no need to reload collectionview – Vivek Goswami Apr 02 '16 at 13:58
i have tried in viewDidLoad viewWillAppear.. but doesn't works – Marie Apr 02 '16 at 14:01
[link](http://stackoverflow.com/questions/14742106/refreshing-a-uicollectionview) – Marie Apr 02 '16 at 14:03
Try this One Link Start Again from starting http://www.appcoda.com/ios-programming-uicollectionview-tutorial/ Or===>>http://stackoverflow.com/questions/17856055/creating-a-uicollectionview-programmatically – Rahul Sharma Apr 02 '16 at 14:08

score 0 · Answer 2 · answered Apr 02 '16 at 14:09

here is updated one. reload data doesn't works

#import "MainCollectionViewController.h"
#import "MainCollectionViewCell.h"


@interface MainCollectionViewController () <UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout>

{
    UICollectionView *colView;
}
@end

@implementation MainCollectionViewController

static NSString * const reuseIdentifier = @"Cell";





- (void)viewDidLoad {
    [super viewDidLoad];


 //  [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];


    self.actressArray = [NSMutableArray arrayWithObjects:@"John", @"Patrick", @"Jack", @"Clara", @"Nicol", @"Amanda", @"Nick", @"Bob", @"Jeff", @"Jerremy", @"Gloria", @"Bred", @"Seth", @"Peter", @"Lous", nil];



    self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    UICollectionViewFlowLayout *layout=[[UICollectionViewFlowLayout alloc] init];
    colView=[[UICollectionView alloc] initWithFrame:self.view.frame collectionViewLayout:layout];
    [colView setDataSource:self]; //დელეგატების კოდით ჩართვა
    [colView setDelegate:self];

    [colView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:reuseIdentifier];
    [colView setBackgroundColor:[UIColor grayColor]]; //ვიუს ბექგრაუნდის ფერი

    UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
    [flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];
    [self.collectionView setCollectionViewLayout:flowLayout];

    [self.view addSubview:colView]; //ვიუზე ჩვენ მიერ გამზადებული ვიუს დაგდება

    [self.collectionView registerClass:[MainCollectionViewCell class] forCellWithReuseIdentifier: reuseIdentifier];

    [colView reloadData];

}



//// In a storyboard-based application, you will often want to do a little preparation before navigation
//- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
//}



- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {

    return 2;
}


- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {


    return _actressArray.count;
}

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



    MainCollectionViewCell *cell = (MainCollectionViewCell *)[collectionView dequeueReusableCellWithReuseIdentifier:reuseIdentifier forIndexPath:indexPath];

    cell.backgroundColor = [UIColor whiteColor];
    cell.layer.cornerRadius = 10;
    cell.layer.borderWidth = 2.0;
    cell.layer.borderColor = [[UIColor lightGrayColor] CGColor];

    UILabel *testLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, cell.bounds.size.width -20 , cell.bounds.size.height)];
    testLabel.text = _actressArray[indexPath.row];
    testLabel.font = [UIFont fontWithName:@"Helvetica" size:12];
    testLabel.textAlignment = NSTextAlignmentCenter;
    testLabel.lineBreakMode = NSLineBreakByWordWrapping;
    testLabel.numberOfLines = 0;

    [cell.contentView addSubview:testLabel];

    return cell;
}



- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
    return CGSizeMake(collectionView.frame.size.width/3.2 , 100);
} //ხაზზე სამისთვის

for starters extend from UICollectionViewController. Also no need to reloadData when in viewDidLoad(), reloadData is only used when your data gets changed. — Gaurav Pal, Apr 02 '16 at 23:24

Working with collectionView and collectionViewCells

2 Answers2