internal diff for PR #209

Summary: https://github.com/Instagram/IGListKit/pull/209

Reviewed By: rnystrom

Differential Revision: D4190633

fbshipit-source-id: 9d382b9ba3f3d20c8b9c48d900650ec354bc9728

Examples/Examples-iOS/IGListKitExamples/ViewControllers/SingleSectionViewController.swift

@@ -0,0 +1,79 @@
+/**
+ Copyright (c) 2016-present, Facebook, Inc. All rights reserved.
+ 
+ The examples provided by Facebook are for non-commercial testing and evaluation
+ purposes only. Facebook reserves all rights not expressly granted.
+ 
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+import UIKit
+import IGListKit
+
+final class SingleSectionViewController: UIViewController, IGListAdapterDataSource, IGListSingleSectionControllerDelegate {
+    
+    lazy var adapter: IGListAdapter = {
+        return IGListAdapter(updater: IGListAdapterUpdater(), viewController: self, workingRangeSize: 0)
+    }()
+    
+    let collectionView = IGListCollectionView(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout())
+    
+    let data = Array(0..<20)
+    
+    // MARK: - Lifecycle
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+
+        view.addSubview(collectionView)
+        adapter.collectionView = collectionView
+        adapter.dataSource = self
+    }
+    
+    override func viewDidLayoutSubviews() {
+        super.viewDidLayoutSubviews()
+        collectionView.frame = view.bounds
+    }
+    
+    //MARK: - IGListAdapterDataSource
+    
+    func objects(for listAdapter: IGListAdapter) -> [IGListDiffable] {
+        return data as [IGListDiffable]
+    }
+    
+    func listAdapter(_ listAdapter: IGListAdapter, sectionControllerFor object: Any) -> IGListSectionController {
+        let configureBlock = { (item: Any, cell: UICollectionViewCell) in
+            guard let cell = cell as? NibCell, let number = item as? Int else { return }
+            cell.textLabel.text = "Cell: \(number + 1)"
+        }
+        
+        let sizeBlock = { (item: Any, context: IGListCollectionContext?) -> CGSize in
+            guard let context = context else { return CGSize() }
+            return CGSize(width: context.containerSize.width, height: 44)
+        }
+        let sectionController = IGListSingleSectionController(nibName: NibCell.nibName,
+                                                              bundle: nil,
+                                                              configureBlock: configureBlock,
+                                                              sizeBlock: sizeBlock)
+        sectionController.selectionDelegate = self
+        
+        return sectionController
+    }
+    
+    func emptyView(for listAdapter: IGListAdapter) -> UIView? { return nil }
+    
+    // MARK: - IGListSingleSectionControllerDelegate
+    
+    func didSelect(_ sectionController: IGListSingleSectionController) {
+        let section = adapter.section(for: sectionController) + 1
+        let alert = UIAlertController(title: "Section \(section) was selected \u{1F389}", message: nil, preferredStyle: .alert)
+        alert.addAction(UIAlertAction(title: "Dismiss", style: .default, handler: nil))
+        present(alert, animated: true, completion: nil)
+    }
+    
+}