14869 Don’t set the loading state when refreshing

When we pull to refresh, the built in controller shows a loading indicator.

If we set our state to `loading`, we also showed a ghost cell at the bottom of the list.

On a pull to refresh, it’s unlikely that the list is going to get longer – more likely, the full first page of results will be shown, so it’ll be the same length or shorter.

This commit prevents us from showing the ghost cell on refresh.

Author: joshheald

WooCommerce/Classes/POS/Controllers/PointOfSaleItemsController.swift

@@ -11,6 +11,8 @@ protocol PointOfSaleItemsControllerProtocol {
     var itemsViewState: ItemsViewState { get }
     /// Loads the first page of items for a given base item.
     func loadItems(base: ItemListBaseItem) async
+    /// Refreshes the items for a given base item – will result in showing only the first page.
+    func refreshItems(base: ItemListBaseItem) async
     /// Loads the next page of items for a given base item.
     func loadNextItems(base: ItemListBaseItem) async
 }
@@ -31,6 +33,16 @@ protocol PointOfSaleItemsControllerProtocol {
 
     @MainActor
     func loadItems(base: ItemListBaseItem) async {
+        setLoadingState(base: base)
+        await loadFirstPage(base: base)
+    }
+
+    @MainActor func refreshItems(base: ItemListBaseItem) async {
+        await loadFirstPage(base: base)
+    }
+
+    @MainActor
+    private func loadFirstPage(base: ItemListBaseItem) async {
         switch base {
         case .root:
             await loadRootItems()
@@ -41,13 +53,6 @@ protocol PointOfSaleItemsControllerProtocol {
 
     @MainActor
     private func loadRootItems() async {
-        let items = itemsViewState.itemsStack.root.items
-        if items.isEmpty {
-            itemsViewState.containerState = .loading
-        } else {
-            itemsViewState.itemsStack.root = .loading(items)
-        }
-
         do {
             try await paginationTracker.resync { [weak self] pageNumber in
                 guard let self else { return true }
@@ -95,9 +100,6 @@ protocol PointOfSaleItemsControllerProtocol {
 
     @MainActor
     private func loadChildItems(for parent: POSItem) async {
-        let items = itemsViewState.itemsStack.itemStates[parent]?.items ?? []
-        updateState(for: parent, to: .loading(items))
-
         let paginationTracker = paginationTracker(for: parent)
         do {
             try await paginationTracker.resync { [weak self] pageNumber in
@@ -155,6 +157,32 @@ protocol PointOfSaleItemsControllerProtocol {
     }
 }
 
+@available(iOS 17.0, *)
+private extension PointOfSaleItemsController {
+    func setLoadingState(base: ItemListBaseItem) {
+        switch base {
+        case .root:
+            setRootLoadingState()
+        case .parent(let parent):
+            setChildLoadingState(for: parent)
+        }
+    }
+
+    func setRootLoadingState() {
+        let items = itemsViewState.itemsStack.root.items
+        if items.isEmpty {
+            itemsViewState.containerState = .loading
+        } else {
+            itemsViewState.itemsStack.root = .loading(items)
+        }
+    }
+
+    func setChildLoadingState(for parent: POSItem) {
+        let items = itemsViewState.itemsStack.itemStates[parent]?.items ?? []
+        updateState(for: parent, to: .loading(items))
+    }
+}
+
 @available(iOS 17.0, *)
 private extension PointOfSaleItemsController {
     /// Fetches items given a page number and appends new unique items to the `allItems` array.

WooCommerce/Classes/POS/Models/PointOfSaleAggregateModel.swift

@@ -93,6 +93,11 @@ extension PointOfSaleAggregateModel {
         await itemsController.loadItems(base: base)
     }
 
+    @MainActor
+    func refreshItems(base: ItemListBaseItem) async {
+        await itemsController.refreshItems(base: base)
+    }
+
     @MainActor
     func loadNextItems(base: ItemListBaseItem) async {
         await itemsController.loadNextItems(base: base)

WooCommerce/Classes/POS/Presentation/ItemListView.swift

@@ -147,7 +147,7 @@ private extension ItemListView {
             ChildItemList(parentItem: parentItem, title: parentProduct.name)
                 .refreshable {
                     ServiceLocator.analytics.track(.pointOfSaleVariationsPullToRefresh)
-                    await posModel.loadItems(base: .parent(parentItem))
+                    await posModel.refreshItems(base: .parent(parentItem))
                 }
         default:
             EmptyView()

WooCommerce/Classes/POS/Presentation/PointOfSaleDashboardView.swift

@@ -90,7 +90,7 @@ struct PointOfSaleDashboardView: View {
                     ItemListView()
                         .refreshable {
                             ServiceLocator.analytics.track(.pointOfSaleProductsPullToRefresh)
-                            await posModel.loadItems(base: .root)
+                            await posModel.refreshItems(base: .root)
                         }
                         .accessibilitySortPriority(2)
                         .transition(.move(edge: .leading))

WooCommerce/Classes/POS/Utils/PreviewHelpers.swift

@@ -75,6 +75,10 @@ final class PointOfSalePreviewItemsController: PointOfSaleItemsControllerProtoco
         }
     }
 
+    func refreshItems(base: ItemListBaseItem) async {
+        await loadItems(base: base)
+    }
+
     func loadNextItems(base: ItemListBaseItem) async {
         itemsViewState = ItemsViewState(containerState: .content, itemsStack: ItemsStackState(root: .loading(mockItems),
                                                                                               itemStates: [:]))