View with Continuous Scroll; Both Horizontal and Vertical

View with continuous scroll; both horizontal and vertical

You can get infinite scrolling, by using the technique of re-centering the UIScrollView after you get a certain distance away from the center. First, you need to make the contentSize big enough that you can scroll a bit, so I return 4 times the number of items in my sections and 4 times the number of sections, and use the mod operator in the cellForItemAtIndexPath method to get the right index into my array. You then have to override layoutSubviews in a subclass of UICollectionView to do the re-centering (this is demonstrated in the WWDC 2011 video, "Advanced Scroll View Techniques"). Here is the controller class that has the collection view (set up in IB) as a subview:

#import "ViewController.h"
#import "MultpleLineLayout.h"
#import "DataCell.h"

@interface ViewController ()
@property (weak,nonatomic) IBOutlet UICollectionView *collectionView;
@property (strong,nonatomic) NSArray *theData;
@end

@implementation ViewController

- (void)viewDidLoad {
    self.theData = @[@[@"1",@"2",@"3",@"4",@"5"], @[@"6",@"7",@"8",@"9",@"10"],@[@"11",@"12",@"13",@"14",@"15"],@[@"16",@"17",@"18",@"19",@"20"]];
    MultpleLineLayout *layout = [[MultpleLineLayout alloc] init];
    self.collectionView.collectionViewLayout = layout;
    self.collectionView.showsHorizontalScrollIndicator = NO;
    self.collectionView.showsVerticalScrollIndicator = NO;
    layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
    self.view.backgroundColor = [UIColor blackColor];
    [self.collectionView registerClass:[DataCell class] forCellWithReuseIdentifier:@"DataCell"];
    [self.collectionView reloadData];
}


- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section {
    return 20;
}

- (NSInteger)numberOfSectionsInCollectionView: (UICollectionView *)collectionView {
    return 16;
}

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

    DataCell *cell = [collectionView  dequeueReusableCellWithReuseIdentifier:@"DataCell" forIndexPath:indexPath];
    cell.label.text = self.theData[indexPath.section %4][indexPath.row %5];
    return cell;
}

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
   // UICollectionViewCell *item = [collectionView cellForItemAtIndexPath:indexPath];
    NSLog(@"%@",indexPath);

}

Here is the UICollectionViewFlowLayout subclass:

#define space 5
#import "MultpleLineLayout.h"

@implementation MultpleLineLayout { // a subclass of UICollectionViewFlowLayout
    NSInteger itemWidth;
    NSInteger itemHeight;
}

-(id)init {
    if (self = [super init]) {
        itemWidth = 60;
        itemHeight = 60;
    }
    return self;
}

-(CGSize)collectionViewContentSize {
    NSInteger xSize = [self.collectionView numberOfItemsInSection:0] * (itemWidth + space); // "space" is for spacing between cells.
    NSInteger ySize = [self.collectionView numberOfSections] * (itemHeight + space);
    return CGSizeMake(xSize, ySize);
}

- (UICollectionViewLayoutAttributes *)layoutAttributesForItemAtIndexPath:(NSIndexPath *)path {
    UICollectionViewLayoutAttributes* attributes = [UICollectionViewLayoutAttributes layoutAttributesForCellWithIndexPath:path];
    attributes.size = CGSizeMake(itemWidth,itemHeight);
    int xValue = itemWidth/2 + path.row * (itemWidth + space);
    int yValue = itemHeight + path.section * (itemHeight + space);
    attributes.center = CGPointMake(xValue, yValue);
    return attributes;
}


-(NSArray*)layoutAttributesForElementsInRect:(CGRect)rect {
    NSInteger minRow =  (rect.origin.x > 0)?  rect.origin.x/(itemWidth + space) : 0; // need to check because bounce gives negative values  for x.
    NSInteger maxRow = rect.size.width/(itemWidth + space) + minRow;
    NSMutableArray* attributes = [NSMutableArray array];
    for(NSInteger i=0 ; i < self.collectionView.numberOfSections; i++) {
        for (NSInteger j=minRow ; j < maxRow; j++) {
            NSIndexPath* indexPath = [NSIndexPath indexPathForItem:j inSection:i];
            [attributes addObject:[self layoutAttributesForItemAtIndexPath:indexPath]];
        }
    }
    return attributes;
}

And finally, here is the subclass of UICollectionView:

-(void)layoutSubviews {
    [super layoutSubviews];
    CGPoint currentOffset = self.contentOffset;
    CGFloat contentWidth = self.contentSize.width;
    CGFloat contentHeight = self.contentSize.height;
    CGFloat centerOffsetX = (contentWidth - self.bounds.size.width)/ 2.0;
    CGFloat centerOffsetY = (contentHeight - self.bounds.size.height)/ 2.0;
    CGFloat distanceFromCenterX = fabsf(currentOffset.x - centerOffsetX);
    CGFloat distanceFromCenterY = fabsf(currentOffset.y - centerOffsetY);

    if (distanceFromCenterX > contentWidth/4.0) { // this number of 4.0 is arbitrary
        self.contentOffset = CGPointMake(centerOffsetX, currentOffset.y);
    }
    if (distanceFromCenterY > contentHeight/4.0) {
        self.contentOffset = CGPointMake(currentOffset.x, centerOffsetY);
    }
}

table view with both horizontal and vertical scrolling in iphone

Set the UIScrollView contentSize property through code and make sure that UIScrollView contentSize property will have the same height but it would have a greater width than tableView.

OR

You can use an UIScrollView and then inside add the UITableView. This UIScrollView will have the same size that your UITableView have now, but the UIScrollView contentSize property will have the same height but it would have a greater width.

One Horizontal and one vertical UICollectionView placed within a UIScrollView iOS Swift

Do not put your collectionView in scrollView. Instead of doing so, put your horizontal collectionView as headerView in vertical collectionView.

Swift: Vertical scroll within horizontal scroll within vertical scroll

I struggled with this for awhile. I came across this and it has worked very well.

https://github.com/OfTheWolf/TwitterProfile

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