Replacing UITableViewDiffableDataSource with DifferenceKit

AutoCat/Models/Vehicle.swift

@@ -184,15 +184,7 @@ class Vehicle: Object, Decodable, Identifiable, Differentiable, Cloneable {
     var osagoContracts = List<Osago>()
     var ads = List<VehicleAd>()
     
-    var identifier: String = ""
+    var differenceIdentifier: String { self.number }
-    var id: String {
-        if self.identifier.isEmpty {
-            self.identifier = self.number
-        }
-        return self.identifier
-    }
-    
-    var differenceIdentifier: String { id }
     
     func isContentEqual(to source: Vehicle) -> Bool {
         return self == source
@@ -266,27 +258,19 @@ class Vehicle: Object, Decodable, Identifiable, Differentiable, Cloneable {
         if let ads = try container.decodeIfPresent([VehicleAd].self, forKey: .ads) {
             self.ads.append(objectsIn: ads)
         }
-        
-        self.identifier = self.number
     }
     
     required init() {
         super.init()
-        self.identifier = self.number
     }
 	
 	init(_ number: String) {
-        self.identifier = number
 		self.number = number
 		self.addedDate = Date().timeIntervalSince1970
         self.updatedDate = self.addedDate
 	}
     
     func getNumber() -> String {
-        if self.identifier.isEmpty {
-            self.identifier = self.number
-        }
-        
         return self.number
     }
     

AutoCat/Utils/RxRealmDataSource.swift

@@ -5,39 +5,25 @@ import ExceptionCatcher
 
 typealias FilterPredicate<T> = (T) -> Bool
 
-class RealmDiffableDataSourse<Item>: UITableViewDiffableDataSource<DateSection<Item>, Item> where Item: Hashable & ContentEquatable & ContentIdentifiable {
+class RealmSectionedDataSource<Item,Cell>: NSObject, UITableViewDataSource
-    override func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
+        where   Item: Object & Identifiable & Dated & Differentiable & Cloneable,
-        return snapshot().sectionIdentifiers[section].header
+                Cell: UITableViewCell & ConfigurableCell,
-    }
+                Cell.Item == Item {
-    
-    override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
-        return true
-    }
-}
-
-class RealmSectionedDataSource<Item,Cell> where Item: Object & Identifiable & Dated & Differentiable & Cloneable, Cell: UITableViewCell & ConfigurableCell, Cell.Item == Item {
     
     private var tv: UITableView
     private var data: Results<Item>
     private var notificationToken: NotificationToken?
     private var sections: [DateSection<Item>] = []
     private var cellIdentifier: String
-    private var lastUpdateTime = Date()
-    private var dataSource: RealmDiffableDataSourse<Item>!
     private var filterPredicate: FilterPredicate<Item>?
     
     init(table: UITableView, data: Results<Item>, cellIdentifier: String = String(describing: Cell.self)) {
         self.tv = table
         self.data = data
         self.cellIdentifier = cellIdentifier
-        
+        super.init()
-        self.dataSource = RealmDiffableDataSourse<Item>(tableView: table) { tv, ip, model -> UITableViewCell? in
+        self.tv.dataSource = self
-            let cell = tv.dequeueReusableCell(withIdentifier: self.cellIdentifier, for: ip) as? Cell
+        self.tv.reloadData()
-            cell?.configure(with: model)
-            return cell
-        }
-        self.dataSource.defaultRowAnimation = .fade
-        self.tv.dataSource = self.dataSource
         
         self.notificationToken = self.data.observe { changes in
             switch changes {
@@ -50,6 +36,30 @@ class RealmSectionedDataSource<Item,Cell> where Item: Object & Identifiable & Da
             }
         }
     }
+
+    // MARK: - UITableViewDataSource
+
+    func numberOfSections(in tableView: UITableView) -> Int {
+        return self.sections.count
+    }
+
+    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+        return self.sections[section].elements.count
+    }
+
+    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
+        guard let cell = tableView.dequeueReusableCell(withIdentifier: self.cellIdentifier, for: indexPath) as? Cell else {
+            return UITableViewCell()
+        }
+
+        let item = self.sections[indexPath.section].elements[indexPath.row]
+        cell.configure(with: item)
+        return cell
+    }
+
+    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
+        return self.sections[section].header
+    }
     
     // MARK: - Public
     
@@ -62,13 +72,12 @@ class RealmSectionedDataSource<Item,Cell> where Item: Object & Identifiable & Da
         if let predicate = self.filterPredicate {
             items = items.filter(predicate)
         }
-        self.sections = items.groupedByDate()
+
-        var snapshot = NSDiffableDataSourceSnapshot<DateSection<Item>, Item>()
+        let newSections = items.groupedByDate()
-        snapshot.appendSections(self.sections)
+        let changeset = StagedChangeset(source: self.sections, target: newSections)
-        for section in self.sections {
+        self.tv.reload(using: changeset, with: animated ? .fade : .none) { newSects in
-            snapshot.appendItems(section.elements, toSection: section)
+            self.sections = newSects
         }
-        self.dataSource.apply(snapshot, animatingDifferences: animated, completion: nil)
     }
     
     func setFilterPredicate(_ predicate: FilterPredicate<Item>?) {