ios - 如何设置 UICollectionViewCompositionalLayout 标头的样式以与其子列表 .insetGrouped 布局分开?
问题描述
我试图模仿我们在邮件应用程序中找到的外观,其中邮箱的组标题是可折叠的,并且它的子列表使用.insetGrouped
layoutOption 设置样式。
我试图UICollectionLayoutListConfiguration(appearance: .sidebarPlain)
用作配置,但我没有找到一种方法来设置部分的 .insetGrouped 外观
邮件应用:
我最接近这个布局的是:
我正在使用下面的方法来配置我的 ViewController 中的 collectionView。
let mixedListLayout =
UICollectionViewCompositionalLayout { section, env -> NSCollectionLayoutSection? in
let listConfig = UICollectionLayoutListConfiguration(appearance: .insetGrouped)
return NSCollectionLayoutSection.list(using: listConfig, layoutEnvironment: env)
}
collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: mixedListLayout)
collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
collectionView.delegate = self
view.addSubview(collectionView)
对于单元格注册,我的方法是这样的:
let headerRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, SidebarItem> { (cell, _, item) in
var contentConfiguration = UIListContentConfiguration.sidebarHeader()
contentConfiguration.text = item.title
cell.contentConfiguration = contentConfiguration
let outlineDisclosureConfig = UICellAccessory.OutlineDisclosureOptions(style: .header)
cell.accessories = [.outlineDisclosure(displayed: .always, options: outlineDisclosureConfig)]
}
let primaryRowRegistration = UICollectionView.CellRegistration<UICollectionViewListCell, SidebarItem> { (cell, _, item) in
var contentConfiguration = UIListContentConfiguration.sidebarCell()
contentConfiguration.text = item.title
contentConfiguration.image = item.image
cell.contentConfiguration = contentConfiguration
cell.indentationLevel = 0
if let acessoryLabel = item.subtitle {
cell.accessories = [.label(text: acessoryLabel)]
}
cell.accessories.append(.disclosureIndicator())
}
dataSource = UICollectionViewDiffableDataSource<SidebarSection, SidebarItem>(collectionView: collectionView) {
(collectionView, indexPath, item) -> UICollectionViewCell in
switch item.type {
case .header:
return collectionView.dequeueConfiguredReusableCell(using: headerRegistration, for: indexPath, item: item)
case .primaryRow:
return collectionView.dequeueConfiguredReusableCell(using: primaryRowRegistration, for: indexPath, item: item)
}
}
解决方案
在对文档进行了更多阅读之后,我通过在中设置headerMode
to解决了它.firstItemInSection
,UICollectionLayoutListConfiguration
所以我的混合列表布局看起来像这样:
let mixedListLayout =
UICollectionViewCompositionalLayout { section, env -> NSCollectionLayoutSection? in
var listConfig = UICollectionLayoutListConfiguration(appearance: .insetGrouped)
listConfig.headerMode = section == 0 ? .none : .firstItemInSection // Using "first
return NSCollectionLayoutSection.list(using: listConfig, layoutEnvironment: env)
}