What I have to do to get the UICollectionView with

问题:

I'm new in UICollectionView and I decided to create a test using UICollectionView programmatically. So I created a new SingleViewApplication project in Xcode and wrote the follow code:

@interface GzViewController ()

@property (nonatomic, strong) UICollectionView *collectionView;
@property (nonatomic, strong) NSArray *items;

@end

@implementation GzViewController

- (void)viewDidLoad{
    [super viewDidLoad];
    self.items = @[@"Address Book", @"Contact", @"Email", @"Phone", @"SMS", @"Free Text", @"URL", @"WiFi"];
    UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
    self.collectionView = [[UICollectionView alloc] initWithFrame:[self.view frame] collectionViewLayout:flowLayout];
    [self.collectionView setDataSource:self];
    [self.collectionView setDelegate:self];
    [self.collectionView registerClass:[UICollectionViewCell class] forCellWithReuseIdentifier:@"Cell"];
    [self.view addSubview:self.collectionView];
}

#pragma mark - UICollectionView Datasource

- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section {
    return 1;
}

- (NSInteger)numberOfSectionsInCollectionView: (UICollectionView *)collectionView {
    return [self.items count];
}

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

    UICollectionViewCell *cell = [cv dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];
    cell.backgroundColor = [UIColor whiteColor];
    return cell;
}

#pragma mark – UICollectionViewDelegateFlowLayout

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    CGSize retval = CGSizeMake(80, 80);
    return retval;
}

- (UIEdgeInsets)collectionView:
(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
    return UIEdgeInsetsMake(5, 20, 5, 5);
}

And the result was this:

What I have to do to get the UICollectionView with two columns on the screen ?

OSX 10.8.3 Xcode 4.6.2 iOS 6.1

回答1:

You need to switch what you're retuning in numberOfItems and numberOfSections, so that you have only 1 section, not multiple sections with one item per section. Also, change your edge insets to something like (5,60,5,60).