[Framework] Pull to refresh in the Feed List (#13)

This PR contains the work done to implement the pull to refresh into the `FeedListViewController` view controller.

Reviewed-on: #13
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Frameworks/Feed/Bundle/Resources/Catalogs/Localizable.xcstrings

@@ -108,6 +108,18 @@
           }
         }
       }
+    },
+    "view.feed-list.pull-to-refresh.title.text" : {
+      "comment" : "The title for the Pull To Refresh control associated to the table in the Feed List view.",
+      "extractionState" : "manual",
+      "localizations" : {
+        "en" : {
+          "stringUnit" : {
+            "state" : "translated",
+            "value" : "Pull to fetch the latest reviews"
+          }
+        }
+      }
     }
   },
   "version" : "1.0"

Frameworks/Feed/Bundle/Sources/Logic/View Models/FeedListViewModel.swift

@@ -82,7 +82,10 @@ extension FeedListViewController {
                             topWords($0).map(TopWord.init)
                         }
 
-                    items = reviewsAll
+                    items = filter == .all
+                        ? reviewsAll
+                        : reviewsFiltered[filter] ?? []
+                    
                     isFilterEnabled = !items.isEmpty
                 } catch {
                     // TODO: handle this error gracefully.

Frameworks/Feed/Bundle/Sources/UI/View Controllers/FeedListViewController.swift

@@ -51,6 +51,24 @@ public class FeedListViewController: UITableViewController {
             )
         )
     }()
+    
+    private lazy var pullControl = {
+        let control = UIRefreshControl()
+
+        control.attributedTitle = .init(string: NSLocalizedString(
+            .Key.PullToRefresh.title,
+            bundle: .module,
+            comment: .empty
+        ))
+
+        control.addTarget(
+            self,
+            action: #selector(refresh(_:)),
+            for: .valueChanged
+        )
+        
+        return control
+    }()
 
     // MARK: Initialisers
     public init(configuration: Configuration = .init()) {
@@ -73,6 +91,7 @@ public class FeedListViewController: UITableViewController {
         super.viewDidLoad()
 
         setNavigationBar()
+        setView()
         registerTableCells()
         bindViewModel()
         
@@ -103,20 +122,28 @@ public class FeedListViewController: UITableViewController {
         _ tableView: UITableView,
         didSelectRowAt indexPath: IndexPath
     ) {
-        let details = FeedItemViewController(items[indexPath.row])
+        guard let item = viewModel.item(for: indexPath.row) else { return }
-        
+
         tableView.deselectRow(
             at: indexPath,
             animated: true
         )
-
+        
-        navigationController?.pushViewController(details, animated: true)
+        navigationController?.pushViewController(
+            FeedItemViewController(item),
+            animated: true
+        )
     }
     
 }
 
 // MARK: - Helpers
 private extension FeedListViewController {
+
+    // MARK: Actions
+    @objc func refresh(_ sender: AnyObject) {
+        self.viewModel.fetch()
+    }
     
     // MARK: Functions
     func bindViewModel() {
@@ -139,10 +166,15 @@ private extension FeedListViewController {
         viewModel.$isLoading
             .dropFirst()
             .filter { $0 == false }
-            .removeDuplicates()
             .receive(on: RunLoop.main)
             .sink { [weak self] _ in
+                self?.pullControl.endRefreshing()
                 self?.tableView.reloadData()
+                self?.tableView.scrollToRow(
+                    at: .init(row: 0, section: 0),
+                    at: .middle,
+                    animated: true
+                )
             }
             .store(in: &cancellables)
     }
@@ -194,7 +226,7 @@ private extension FeedListViewController {
 
         return cell
     }
-    
+
     func registerTableCells() {
         FeedItemCell.register(in: tableView)
         TopWordsCell.register(in: tableView)
@@ -212,6 +244,10 @@ private extension FeedListViewController {
         )
     }
     
+    func setView() {
+        tableView.refreshControl = pullControl
+    }
+    
     func updateFilterMenu(_ option: FilterOption) {
         filterButton
             .menu?
@@ -267,6 +303,10 @@ private extension String {
                 static let filter = "view.feed-list.navigation-bar.button.filter-list.text"
             }
         }
+        
+        enum PullToRefresh {
+            static let title = "view.feed-list.pull-to-refresh.title.text"
+        }
     }
 }