指定UICollectionView的行号和列号

Question

我想显示一个UICollectionView,每行包含2行和100个单元格.

// 1
- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section {

    return 100;
}
// 2
- (NSInteger)numberOfSectionsInCollectionView: (UICollectionView *)collectionView {
    return 2;
}
// 3
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    MyCell *cell = [cv dequeueReusableCellWithReuseIdentifier:@"cell" forIndexPath:indexPath];

        cell.lbl.text = @"Data";

    return cell;
}

我得到这个:

如何为UICollectionView指定行号？我想创建一个2x100表.

Answer 1

试试这个:

// 1
- (NSInteger)collectionView:(UICollectionView *)view numberOfItemsInSection:(NSInteger)section {

    return 2;
}
// 2
- (NSInteger)numberOfSectionsInCollectionView: (UICollectionView *)collectionView {
    return 100;
}
// 3
- (UICollectionViewCell *)collectionView:(UICollectionView *)cv cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    MyCell *cell = [cv dequeueReusableCellWithReuseIdentifier:@"cell" forIndexPath:indexPath];

        cell.lbl.text = @"Data";

    return cell;
}

Answer 2

每行3个单元格..添加此代码.

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

Answer 3

对于Swift:每列3行(使用@SakhshiSingla答案)

override func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int {
  return 1
}

override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return 3
}

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize
    {
        return CGSize(width: collectionView.frame.size.width/3.2, height: 100)
    }

Answer 4

在集合视图中实现n列的更通用的方法是在任何方向兼容的

 func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {

   // flow layout have all the important info like spacing, inset of collection view cell, fetch it to find out the attributes specified in xib file
   guard let flowLayout = collectionViewLayout as? UICollectionViewFlowLayout else {
        return CGSize()
    }

    // subtract section left/ right insets mentioned in xib view

    let widthAvailbleForAllItems =  (collectionView.frame.width - flowLayout.sectionInset.left - flowLayout.sectionInset.right)

    // Suppose we have to create nColunmns
    // widthForOneItem achieved by sunbtracting item spacing if any

    let widthForOneItem = widthAvailbleForAllItems / nColumns - flowLayout.minimumInteritemSpacing


    // here height is mentioned in xib file or storyboard
    return CGSize(width: CGFloat(widthForOneItem), height: (flowLayout.itemSize.height))
 }