iOS 动态表单框架

• 支持 UICollectionView
• 支持 UITableView

• Swift 5.7 (Xcode 14+)
• iOS 13.0+

• Cocoapods

  pod 'SectionKit2', '2.0.0-beta.1'
  or
  pod 'SectionUI', '2.0.0-beta.1'

• Swift Packages URL

  https://github.com/linhay/SectionKit

• 数据选中 SKSelection
• 辅助工具 Shell

通用通用型单元视图可以使用 SectionKit 中已封装的 Section 结构:
- SKCRegistrationSection
- SKCSingleTypeSection

通用型单元视图需要遵守 2 个 Protocol:
1. SKConfigurableView:
- 用于绑定视图与输入数据类型
- 用于确定视图尺寸
2. SKLoadViewProtocol or SKLoadNibProtocol: 用于指定当前视图是代码加载还是从 Xib 加载

• UICollectionViewCell:

  import UIKit
  import SectionKit
  
  class SpacerCell: UICollectionViewCell, SKConfigurableView, SKLoadViewProtocol {
      
      public struct Model {
          public let size: CGSize
          public let backgroundColor: UIColor?
      }
      
      public func config(_ model: Model) {
          self.backgroundColor = model.backgroundColor
      }
      
      public static func preferredSize(limit size: CGSize, model: Model?) -> CGSize {
          guard let model = model else {
              return .zero
          }
          return model.size
      }
      
  }

• UICollectionReusableView:

  import UIKit
  import SectionKit
  
  class SupplementaryView: UICollectionReusableView, SKConfigurableView, SKLoadViewProtocol {
      
      static func preferredSize(limit size: CGSize, model: Void?) -> CGSize {
          return CGSize(width: size.width, height: 44)
      }
      
      func config(_ model: Void) {
          
      }
      
  }

单一数据类型 Section

• 创建 Section

  let model = FLSpacerCell.Model(size: .zero)
  /// 以下 API 完全等价
  let section1 = FLSpacerCell.wrapperToSingleTypeSection([model])
  let section2 = FLSpacerCell.wrapperToSingleTypeSection(model)
  let section3 = SKCSingleTypeSection<FLSpacerCell>([model])
  let section4 = SKCSingleTypeSection<FLSpacerCell>(model)

• 与 UICollectionView 关联

  /// 创建 Section
  let model = FLSpacerCell.Model(size: .zero)
  let section1 = FLSpacerCell.wrapperToSingleTypeSection([model])
  let section2 = FLCustomCell.wrapperToSingleTypeSection(model)
  
  /// manager 与 UICollectionView 关联
  let sectionView = UICollectionView(frame: .zero,collectionViewLayout: UICollectionViewFlowLayout())
  let manager = SKCManager(sectionView: sectionView)
  
  /// 加载 section1, section2
  manager.reload([section1, section2])

• 样式配置

  let section = FLSpacerCell
      .wrapperToSingleTypeSection([model])
  
      /// 配置当前 section 样式
      .setSectionStyle({ section in
          section.minimumLineSpacing = 10
          section.minimumInteritemSpacing = 10
          section.sectionInset = .init(top: 20, left: 20, bottom: 20,right: 20)
      })
  
      /// 加载指定 row 时可以通过 setCellStyle 额外配置 cell 样式
      .setCellStyle { context in
          context.model
          context.row
          context.view
          context.section
      }
  
      /// 配置 headerView & footerView
      .set(supplementary: .header(type: SupplementaryView.self,model: ()))
      .set(supplementary: .header(type: SupplementaryView.self,config: { view in
          view.backgroundColor = .red
      }, size: { limitSize in
          return .init(width: 375, height: 44)
      }))
  
      /// 配置 headerView & footerView, 与上述函数等价
      .set(supplementary: .init(kind: .header, type:SupplementaryView.self, model: ()))
      .set(supplementary: .init(kind: .header, type:SupplementaryView.self, config: { view in
          view.backgroundColor = .red
      }, size: { limitSize in
          return .init(width: 375, height: 44)
      }))
  
      /// 响应 cell 选中事件
      .onCellAction(.selected) { context in
          context.model
          context.row
          context.view()
          context.section
      }
      .onCellAction(.config) { _ in }
      .onCellAction(.willDisplay) { _ in }
      .onCellAction(.didEndDisplay) { _ in }
      
      /// 响应 SupplementaryView 消失事件
      .onSupplementaryAction(.didEndDisplay) { context in
          context.row
          context.type
          context.kind
          context.section
      }
      .onSupplementaryAction(.willDisplay, block: { _ in })

• 数据操作

  修改数据后会刷新响应视图, 无需手动刷新

  let section = FLSpacerCell.wrapperToSingleTypeSection([model])
  /// 重置数据为 models
  _ = section.config(models: [Model])
  section.apply(models: [Model])
  /// 拼接数据至当前数据尾部
  section.append([Model])
  section.insert(at: 0, [Model])
  section.swapAt(0, 1)
  section.remove(0)
  section.remove(supplementary: .header)

• 事件订阅

  let section = FLSpacerCell.wrapperToSingleTypeSection([model])
  
  section.pulishers.cellActionPulisher.sink { context in
      switch context.type {
      case .selected:
          break
      case .willDisplay:
          break
      case .didEndDisplay:
          break
      case .config:
          break
      }
  }
  
  section.pulishers.supplementaryActionPulisher.sink { context in
      switch context.type {
      case .willDisplay:
          break
      case .didEndDisplay:
          break
      }
  }
  
  /// 以下事件依托于 UICollectionViewDataSourcePrefetching 能力
  
  /// 预测需要显示的 row 已经超过当前的 cell 数量
  section.prefetch.loadMorePublisher.sink { _ in
          
  }
      
  /// 预测需要显示的 rows
  section.prefetch.prefetchPublisher.sink { rows in
          
  }
      
  section.prefetch.cancelPrefetchingPublisher.sink { rows in
          
  }

复数数据类型 Section, 生成后所有的操作都会通过 diff 来更新视图

• 创建 Section

  /// 以下方式完全等价
  
  /// 由 @resultBuilder 提供语法支持
  let section1 = SKCRegistrationSection {
      SupplementaryView.registration((), for: .header)
      SupplementaryView.registration((), for: .footer)
      FLSpacerCell.registration(model)
      FLCustomCell.registration(model)
      FLSpacerCell.registration(model)
  }
  
  let section2 = SKCRegistrationSection([.header: SupplementaryView.registration((), for: .header),
                                         .footer: SupplementaryView.registration((), for: .footer)],
                                        [FLSpacerCell.registration(model),
                                         FLCustomCell.registration(model),
                                         FLSpacerCell.registration(model)])

• 与 UICollectionView 关联

  /// manager 与 UICollectionView 关联
  let sectionView = UICollectionView(frame: .zerocollectionViewLayout: UICollectionViewFlowLayout())
  let manager = SKCRegistrationManager(sectionView:sectionView)
  /// 加载 section1, section2
  manager.reload([section1, section2])

• 样式配置

  let section = SKCRegistrationSection {
      SupplementaryView
          .registration((), for: .header)
          /// 配置 supplementary 样式
          .viewStyle({ view, model in })
          .onWillDisplay { model in }
          .onEndDisplaying { model in }
          
      FLSpacerCell
          .registration(model)
          /// 配置 cell 样式
          .viewStyle({ view, model in })
          /// 响应 cell 选中事件
          .onSelected { model in }
          .onHighlight { model in }
          .onWillDisplay { model in }
          .onEndDisplaying { model in }
          // ...
  }
  /// 配置 section 样式
  .setSectionStyle { section in
      section.minimumInteritemSpacing = 10
      section.minimumLineSpacing = 10
      section.sectionInset = .init(top: 10, left: 10, bottom: 10,right: 10)
  }

• 数据操作

  let section = SKCRegistrationSection {
      // ...
  }
  
  /// 重置所有视图
  section.apply(on: self) { (self, section) in
      SupplementaryView.registration((), for: .header)
      FLSpacerCell.registration(model)
      // ...
  }
  
  section.apply {
      SupplementaryView.registration((), for: .header)
      FLSpacerCell.registration(model)
      // ...
  }
  
  /// 重置所有 Cell 视图
  section.apply(cell: FLSpacerCell.registration(model))
  section.apply(cell: [FLSpacerCell.registration(model)])
  
  /// 重置所有 Supplementary 视图
  section.apply(supplementary: SupplementaryView.registration((), for: .header))
  section.apply(supplementary: [SupplementaryView.registration((), for: .header),
                                SupplementaryView.registration((), for: .footer)])
  section.apply(supplementary: [.header: SupplementaryView.registration((), for: .header)])
  
  // 局部操作
  let cell = FLSpacerCell.registration(model)
  section.delete(cell: cell)
  section.reload(cell: cell)
  
  // 局部操作
  let view = SupplementaryView.registration((), for: .header)
  section.insert(supplementary: view)
  section.delete(supplementary: view)

• 事件订阅

  /// 以下事件依托于 UICollectionViewDataSourcePrefetching 能力
  
  /// 预测需要显示的 row 已经超过当前的 cell 数量
  section.prefetch.loadMorePublisher.sink { _ in
          
  }
      
  /// 预测需要显示的 rows
  section.prefetch.prefetchPublisher.sink { rows in
          
  }
      
  section.prefetch.cancelPrefetchingPublisher.sink { rows in
          
  }

最基础的 protocol, SKCRegistrationSection, SKCSingleTypeSection 由此封装

• 创建 Section

  import UIKit
  import SectionKit
  
  class CustomSection: SKCSectionProtocol {
      
      var sectionInjection: SKCSectionInjection?
      
      var minimumLineSpacing: CGFloat = 10
      var minimumInteritemSpacing: CGFloat = 10
      var sectionInset: UIEdgeInsets = .init(top: 20, left: 20, bottom: 20, right: 20)
      
      var itemCount: Int { 0 }
      
      func config(sectionView: UICollectionView) {
          register(StringCell.self)
      }
      
      func itemSize(at row: Int) -> CGSize {
          return .init(width: 44, height: 44)
      }
      
      func item(at row: Int) -> UICollectionViewCell {
          let cell = dequeue(at: row) as StringCell
          return cell
      }
      
      func item(selected row: Int) {}
      func item(willDisplay view: UICollectionViewCell, row: Int) {}
      func item(didEndDisplaying view: UICollectionViewCell, row: Int) {}
      func item(didBeginMultipleSelectionInteraction row: Int) {}
      /// ...
  }

• 与 UICollectionView 关联

  /// 创建 Section
  let section1 = CustomSection()
  let section2 = CustomSection()
  
  /// manager 与 UICollectionView 关联
  let sectionView = UICollectionView(frame: .zero,collectionViewLayout: UICollectionViewFlowLayout())
  let manager = SKCManager(sectionView: sectionView)
  
  /// 加载 section1, section2
  manager.reload([section1, section2])

• 数据操作

  • 无默认实现

• 事件订阅

  • 无默认实现