在UICollectionViewFlowLayout-对象上使用setMinimumLineSpacing:和setMinimumInteritemSpacing:。

您可以对UICollectionView使用collectionView:layout:insetForSectionAtIndex:方法，或设置附加到UICollectionView的UICollectionViewFlowLayout对象的sectionInset属性：

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{
return UIEdgeInsetsMake(top, left, bottom, right);
}

或

UICollectionViewFlowLayout *aFlowLayout = [[UICollectionViewFlowLayout alloc] init];
[aFlowLayout setSectionInset:UIEdgeInsetsMake(top, left, bottom, right)];

针对斯威夫特5进行更新

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
return UIEdgeInsets(top: 25, left: 15, bottom: 0, right: 5)
}

要在完全的UICollectionView上添加间距：

UICollectionViewFlowLayout *flow = (UICollectionViewFlowLayout*) collection.collectionViewLayout;
flow.sectionInset = UIEdgeInsetsMake(topMargin, left, bottom, right);

要使用间距_ABC_同一行（如果水平滚动，则为列）的0个元素及其大小：

flow.itemSize = ...;
flow.minimumInteritemSpacing = ...;

要在CollectionItem之间放置空格，请使用此

在viewdidload中写下这两行

UICollectionViewFlowLayout *collectionViewLayout = (UICollectionViewFlowLayout*)self.collectionView.collectionViewLayout;
collectionViewLayout.sectionInset = UIEdgeInsetsMake(<CGFloat top>, <CGFloat left>, <CGFloat bottom>, <CGFloat right>)

只是为了更正此页面中的一些错误信息：

1-最小项间距：同一行中的项之间使用的最小间距。

默认值：10.0。

（对于垂直滚动网格，此值表示同一行中项目之间的最小间距。）

2-最小线间距：网格中项目行之间使用的最小间距。

参考：http://developer.apple.com/library/ios/#documentation/uikit/reference/UICollectionViewFlowLayout_class/Reference/Reference.html

在Interface Builder中设置插图，如下面的屏幕截图所示

将导致类似这样的结果：

要在每个部分之间添加10px的间隔，只需编写以下内容

flowLayout.sectionInset = UIEdgeInsetsMake(0.0, 0.0,10,0);

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
return UIEdgeInsetsMake(7, 10, 5, 10);
}

斯威夫特4

    let flow = collectionView.collectionViewLayout as! UICollectionViewFlowLayout
// If you create collectionView programmatically then just create this flow by UICollectionViewFlowLayout() and init a collectionView by this flow.


let itemSpacing: CGFloat = 3
let itemsInOneLine: CGFloat = 3
flow.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)


//collectionView.frame.width is the same as  UIScreen.main.bounds.size.width here.
let width = UIScreen.main.bounds.size.width - itemSpacing * CGFloat(itemsInOneLine - 1)
flow.itemSize = CGSize(width: floor(width/itemsInOneLine), height: width/itemsInOneLine)
flow.minimumInteritemSpacing = 3
flow.minimumLineSpacing = itemSpacing

编辑

如果要更改为水平scrollDirction：

flow.scrollDirection = .horizontal

注意

如果您在一行中设置的项目不正确，请检查您的集合视图是否有填充。那就是：

let width = UIScreen.main.bounds.size.width - itemSpacing * CGFloat(itemsInOneLine - 1)

应为CollectionView宽度。

使用collectionViewFlowLayout.sectionInset或collectionView:layout:insetForSectionAtIndex:正确。

但是，如果您的CollectionView有多个部分，并且您希望为整个CollectionView添加边距，我建议使用ScrollView ContentInset：

UIEdgeInsets collectionViewInsets = UIEdgeInsetsMake(50.0, 0.0, 30.0, 0.0);
self.collectionView.contentInset = collectionViewInsets;
self.collectionView.scrollIndicatorInsets = UIEdgeInsetsMake(collectionViewInsets.top, 0, collectionViewInsets.bottom, 0);

要向指定的单元格添加边距，可以使用此自定义流动布局。 https://github.com/voyages-sncf-technologies/VSCollectionViewCellInsetFlowLayout/

extension ViewController : VSCollectionViewDelegateCellInsetFlowLayout
{
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForItemAt indexPath: IndexPath) -> UIEdgeInsets {
if indexPath.item == 0 {
return UIEdgeInsets(top: 0, left: 0, bottom: 10, right: 0)
}
return UIEdgeInsets.zero
}
}

现代Swift，自动布局计算

虽然这个帖子已经包含了一堆有用的答案，但我想根据William Hu的答案添加一个现代雨燕版本。它还改善了两件事：

• 现在，不同行之间的间距将始终与同一行中项目之间的间距相匹配。
• 通过设置最小宽度， 代码自动计算一行中的项数，并 将该样式应用于流布局。

代码如下：

// Create flow layout
let flow = UICollectionViewFlowLayout()


// Define layout constants
let itemSpacing: CGFloat = 1
let minimumCellWidth: CGFloat = 120
let collectionViewWidth = collectionView!.bounds.size.width


// Calculate other required constants
let itemsInOneLine = CGFloat(Int((collectionViewWidth - CGFloat(Int(collectionViewWidth / minimumCellWidth) - 1) * itemSpacing) / minimumCellWidth))
let width = collectionViewWidth - itemSpacing * (itemsInOneLine - 1)
let cellWidth = floor(width / itemsInOneLine)
let realItemSpacing = itemSpacing + (width / itemsInOneLine - cellWidth) * itemsInOneLine / max(1, itemsInOneLine - 1)


// Apply values
flow.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
flow.itemSize = CGSize(width: cellWidth, height: cellWidth)
flow.minimumInteritemSpacing = realItemSpacing
flow.minimumLineSpacing = realItemSpacing


// Apply flow layout
collectionView?.setCollectionViewLayout(flow, animated: false)

在Objective-C中

CGFloat spacing = 5;
UICollectionViewFlowLayout *flow = (UICollectionViewFlowLayout*)_habbitCollectionV.collectionViewLayout;
flow.sectionInset = UIEdgeInsetsMake(0, spacing, 0, spacing);
CGFloat itemsPerRow = 2;
CGRect screenRect = [[UIScreen mainScreen] bounds];
CGFloat oneMore = itemsPerRow + 1;
CGFloat width = screenRect.size.width - spacing * oneMore;
CGFloat height = width / itemsPerRow;


flow.itemSize = CGSizeMake(floor(height), height);
flow.minimumInteritemSpacing = spacing;
flow.minimumLineSpacing = spacing;

您只需更改itemsPerRow值，它就会相应地更新每行的项数。此外，如果需要更多或更少的常规间距，可以更改间距值。

在Swift 4和AutoLayout中，您可以像这样使用章节插图：

let layout = UICollectionViewFlowLayout()
layout.scrollDirection = .vertical
layout.itemSize = CGSize(width: (view.frame.width-40)/2, height: (view.frame.width40)/2) // item size
layout.sectionInset = UIEdgeInsetsMake(10, 10, 10, 10) // here you can add space to 4 side of item
collectionView = UICollectionView(frame: self.view.bounds, collectionViewLayout: layout) // set layout to item
collectionView?.register(ProductCategoryCell.self, forCellWithReuseIdentifier: cellIdentifier) // registerCell
collectionView?.backgroundColor = .white // background color of UICollectionView
view.addSubview(collectionView!) // add UICollectionView to view

设置附加到UICollectionView的UICollectionViewFlowLayout对象的insetForSectionAt属性

确保添加此协议

UICollectionViewDelegateFlowLayout

斯威夫特

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
return UIEdgeInsets (top: top, left: left, bottom: bottom, right: right)
}

目标-C

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout insetForSectionAtIndex:(NSInteger)section{
return UIEdgeInsetsMake(top, left, bottom, right);
}