Bulk Editing: Add selection state to products list

Networking/Networking/Model/Product/Product.swift

@@ -662,3 +662,12 @@ private extension Product {
 enum ProductDecodingError: Error {
     case missingSiteID
 }
+
+// MARK: - Hashable Conformance
+//
+extension Product: Hashable {
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(siteID)
+        hasher.combine(productID)
+    }
+}

WooCommerce/Classes/ViewRelated/Products/ProductsListViewModel.swift

@@ -0,0 +1,28 @@
+import Foundation
+import Yosemite
+
+/// View model for `ProductsViewController`. Only stores logic related to Bulk Editing.
+///
+class ProductListViewModel {
+    private var selectedProducts: Set<Product> = .init()
+
+    var selectedProductsCount: Int {
+        selectedProducts.count
+    }
+
+    func productIsSelected(_ productToCheck: Product) -> Bool {
+        return selectedProducts.contains(productToCheck)
+    }
+
+    func selectProduct(_ selectedProduct: Product) {
+        selectedProducts.insert(selectedProduct)
+    }
+
+    func deselectProduct(_ selectedProduct: Product) {
+        selectedProducts.remove(selectedProduct)
+    }
+
+    func deselectAll() {
+        selectedProducts.removeAll()
+    }
+}

WooCommerce/Classes/ViewRelated/Products/ProductsViewController.swift

@@ -9,6 +9,8 @@ import class AutomatticTracks.CrashLogging
 ///
 final class ProductsViewController: UIViewController, GhostableViewController {
 
+    let viewModel: ProductListViewModel = .init()
+
     /// Main TableView
     ///
     @IBOutlet weak var tableView: UITableView!
@@ -264,7 +266,24 @@ private extension ProductsViewController {
     }
 
     @objc func startBulkEditing() {
-        // TODO-8517: implement selection state
+        tableView.setEditing(true, animated: true)
+
+        // Disable pull-to-refresh while editing
+        refreshControl.removeFromSuperview()
+
+        configureNavigationBarForEditing()
+        showOrHideToolbar()
+    }
+
+    @objc func finishBulkEditing() {
+        viewModel.deselectAll()
+        tableView.setEditing(false, animated: true)
+
+        // Enable pull-to-refresh
+        tableView.addSubview(refreshControl)
+
+        configureNavigationBar()
+        showOrHideToolbar()
     }
 }
 
@@ -330,12 +349,8 @@ private extension ProductsViewController {
                                              target: self,
                                              action: #selector(startBulkEditing))
                 button.accessibilityTraits = .button
-                button.accessibilityLabel = NSLocalizedString("Edit products",
-                                                              comment: "Action to start bulk editing of products")
-                button.accessibilityHint = NSLocalizedString(
-                    "Edit status or price for multiple products at once",
-                    comment: "VoiceOver accessibility hint, informing the user the button can be used to bulk edit products"
-                )
+                button.accessibilityLabel = Localization.bulkEditingNavBarButtonTitle
+                button.accessibilityHint = Localization.bulkEditingNavBarButtonHint
 
                 return button
             }()
@@ -345,6 +360,26 @@ private extension ProductsViewController {
         navigationItem.rightBarButtonItems = rightBarButtonItems
     }
 
+    func configureNavigationBarForEditing() {
+        configureNavigationBarTitleForEditing()
+        configureNavigationBarRightButtonItemsForEditing()
+    }
+
+    func configureNavigationBarTitleForEditing() {
+        let selectedProducts = viewModel.selectedProductsCount
+        if selectedProducts == 0 {
+            navigationItem.title = Localization.bulkEditingTitle
+        } else {
+            navigationItem.title = String.localizedStringWithFormat(Localization.bulkEditingItemsTitle, String(selectedProducts))
+        }
+    }
+
+    func configureNavigationBarRightButtonItemsForEditing() {
+        navigationItem.rightBarButtonItems = [UIBarButtonItem(barButtonSystemItem: .cancel,
+                                                              target: self,
+                                                              action: #selector(finishBulkEditing))]
+    }
+
     /// Apply Woo styles.
     ///
     func configureMainView() {
@@ -371,6 +406,8 @@ private extension ProductsViewController {
         tableView.tableFooterView = footerSpinnerView
         tableView.separatorStyle = .none
 
+        tableView.allowsMultipleSelectionDuringEditing = true
+
         // Adds the refresh control to table view manually so that the refresh control always appears below the navigation bar title in
         // large or normal size to be consistent with Dashboard and Orders tab with large titles workaround.
         // If we do `tableView.refreshControl = refreshControl`, the refresh control appears in the navigation bar when large title is shown.
@@ -447,6 +484,11 @@ private extension ProductsViewController {
     /// if there is 1 or more products, toolbar will be visible
     ///
     func showOrHideToolbar() {
+        guard !tableView.isEditing else {
+            toolbar.isHidden = true
+            return
+        }
+
         toolbar.isHidden = filters.numberOfActiveFilters == 0 ? isEmpty : false
     }
 }
@@ -627,13 +669,28 @@ extension ProductsViewController: UITableViewDelegate {
     }
 
     func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
-        tableView.deselectRow(at: indexPath, animated: true)
+        let product = resultsController.object(at: indexPath)
 
-        ServiceLocator.analytics.track(.productListProductTapped)
+        if tableView.isEditing {
+            viewModel.selectProduct(product)
+            configureNavigationBarTitleForEditing()
+        } else {
+            tableView.deselectRow(at: indexPath, animated: true)
 
-        let product = resultsController.object(at: indexPath)
+            ServiceLocator.analytics.track(.productListProductTapped)
+
+            didSelectProduct(product: product)
+        }
+    }
+
+    func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
+        guard tableView.isEditing else {
+            return
+        }
 
-        didSelectProduct(product: product)
+        let product = resultsController.object(at: indexPath)
+        viewModel.deselectProduct(product)
+        configureNavigationBarTitleForEditing()
     }
 
     func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
@@ -646,6 +703,14 @@ extension ProductsViewController: UITableViewDelegate {
         // the actual value. AKA no flicker!
         //
         estimatedRowHeights[indexPath] = cell.frame.height
+
+        // Restore cell selection state
+        let product = resultsController.object(at: indexPath)
+        if self.viewModel.productIsSelected(product) {
+            tableView.selectRow(at: indexPath, animated: false, scrollPosition: .none)
+        } else {
+            tableView.deselectRow(at: indexPath, animated: false)
+        }
     }
 
     func scrollViewDidScroll(_ scrollView: UIScrollView) {
@@ -1046,4 +1111,22 @@ private extension ProductsViewController {
         static let headerContainerInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
         static let toolbarButtonInsets = UIEdgeInsets(top: 12, left: 16, bottom: 12, right: 16)
     }
+
+    enum Localization {
+
+        static let bulkEditingNavBarButtonTitle = NSLocalizedString("Edit products", comment: "Action to start bulk editing of products")
+        static let bulkEditingNavBarButtonHint = NSLocalizedString(
+            "Edit status or price for multiple products at once",
+            comment: "VoiceOver accessibility hint, informing the user the button can be used to bulk edit products"
+        )
+
+        static let bulkEditingTitle = NSLocalizedString(
+            "Select items",
+            comment: "Title that appears on top of the Product List screen when bulk editing starts."
+        )
+        static let bulkEditingItemsTitle = NSLocalizedString(
+            "%1$@ selected",
+            comment: "Title that appears on top of the Product List screen during bulk editing. Reads like: 2 selected"
+        )
+    }
 }

WooCommerce/WooCommerce.xcodeproj/project.pbxproj

@@ -1218,6 +1218,7 @@
 		ABC35528D2D6BE6F516E5CEF /* InPersonPaymentsOnboardingError.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABC35A4B736A0B2D8348DD08 /* InPersonPaymentsOnboardingError.swift */; };
 		ABC35F18E744C5576B986CB3 /* InPersonPaymentsUnavailableView.swift in Sources */ = {isa = PBXBuildFile; fileRef = ABC35055F8AC8C8EB649F421 /* InPersonPaymentsUnavailableView.swift */; };
 		AE1CC33829129A010021C8EF /* LinkBehavior.swift in Sources */ = {isa = PBXBuildFile; fileRef = AE1CC33729129A010021C8EF /* LinkBehavior.swift */; };
+		AE2E5F6629685CF8009262D3 /* ProductsListViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = AE2E5F6529685CF8009262D3 /* ProductsListViewModel.swift */; };
 		AE3AA889290C303B00BE422D /* WebKitViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = AE3AA888290C303B00BE422D /* WebKitViewController.swift */; };
 		AE3AA88B290C30B900BE422D /* WebViewControllerConfiguration.swift in Sources */ = {isa = PBXBuildFile; fileRef = AE3AA88A290C30B900BE422D /* WebViewControllerConfiguration.swift */; };
 		AE3AA88D290C30E800BE422D /* WebProgressView.swift in Sources */ = {isa = PBXBuildFile; fileRef = AE3AA88C290C30E800BE422D /* WebProgressView.swift */; };
@@ -3259,6 +3260,7 @@
 		ABC353433EABC5F0EC796222 /* CardReaderSettingsSearchingViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CardReaderSettingsSearchingViewController.swift; sourceTree = "<group>"; };
 		ABC35A4B736A0B2D8348DD08 /* InPersonPaymentsOnboardingError.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = InPersonPaymentsOnboardingError.swift; sourceTree = "<group>"; };
 		AE1CC33729129A010021C8EF /* LinkBehavior.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LinkBehavior.swift; sourceTree = "<group>"; };
+		AE2E5F6529685CF8009262D3 /* ProductsListViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProductsListViewModel.swift; sourceTree = "<group>"; };
 		AE3AA888290C303B00BE422D /* WebKitViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WebKitViewController.swift; sourceTree = "<group>"; };
 		AE3AA88A290C30B900BE422D /* WebViewControllerConfiguration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WebViewControllerConfiguration.swift; sourceTree = "<group>"; };
 		AE3AA88C290C30E800BE422D /* WebProgressView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WebProgressView.swift; sourceTree = "<group>"; };
@@ -6783,6 +6785,7 @@
 				02A65300246AA63600755A01 /* ProductDetailsFactory.swift */,
 				B92FF9AF27FC7821005C34E3 /* ProductsViewController.xib */,
 				0260F40023224E8100EDA10A /* ProductsViewController.swift */,
+				AE2E5F6529685CF8009262D3 /* ProductsListViewModel.swift */,
 				020DD49023239DD6005822B1 /* PaginatedListViewControllerStateCoordinator.swift */,
 				02564A89246CDF6100D6DB2A /* ProductsTopBannerFactory.swift */,
 				0279F0D9252DB4BE0098D7DE /* ProductVariationDetailsFactory.swift */,
@@ -10355,6 +10358,7 @@
 				CE1CCB402056F21C000EE3AC /* Style.swift in Sources */,
 				45EF7984244F26BB00B22BA2 /* Array+IndexPath.swift in Sources */,
 				02E6B97823853D81000A36F0 /* TitleAndValueTableViewCell.swift in Sources */,
+				AE2E5F6629685CF8009262D3 /* ProductsListViewModel.swift in Sources */,
 				CC770C8A27B1497700CE6ABC /* SearchHeader.swift in Sources */,
 				02BAB02724D13A6400F8B06E /* ProductVariationFormActionsFactory.swift in Sources */,
 				45CDAFAE2434CFCA00F83C22 /* ProductCatalogVisibilityViewController.swift in Sources */,