fix: showing/hiding empty conversation list placeholder - WPB-14386

wire-ios/Wire-iOS Tests/ConversationList/Container/MockConversationListContainer.swift

@@ -111,4 +111,8 @@ final class MockConversationListContainer: UIViewController, ConversationListCon
     ) {
         // no-op
     }
+
+    func conversationListViewControllerViewModelDidReloadContent(_ viewModel: ConversationListViewController.ViewModel) {
+        // no - op
+    }
 }

wire-ios/Wire-iOS/Sources/UserInterface/ConversationList/Container/ConversationListViewController+NavigationBar/ConversationListViewController+NavigationBar.swift

@@ -54,6 +54,10 @@
         }
     }
 
+    func conversationListViewControllerViewModelDidReloadContent(_ viewModel: ViewModel) {
+        configureEmptyPlaceholder()
+    }
+
     func conversationListViewControllerViewModelRequiresUpdatingLegalHoldIndictor(_ viewModel: ViewModel) {
         if mainSplitViewState == .collapsed {
             setupLeftNavigationBarButtonItems()
@@ -176,7 +180,7 @@
             systemName: "line.3.horizontal.decrease.circle.fill",
             withConfiguration: symbolConfiguration
         )!
 
         var selectedFilterImage: UIImage = switch listContentController.listViewModel.selectedFilter {
         case .favorites, .groups, .oneOnOne, .folder:
             filledFilterImage
@@ -256,7 +260,7 @@
             SemanticColors.Button.borderBarItem.resolvedColor(with: traitCollection),
             for: .normal
         )
         newConversationBarButton.layer.cornerRadius = 12
         newConversationBarButton.contentEdgeInsets = UIEdgeInsets(top: 8, left: 12, bottom: 8, right: 12)
         newConversationBarButton.bounds.size = newConversationBarButton.systemLayoutSizeFitting(CGSize(
             width: .max,
@@ -428,7 +432,7 @@
         guard case .pending = viewModel.selfUserLegalHoldSubject.legalHoldStatus else {
             return
         }
 
         ZClientViewController.shared?.legalHoldDisclosureController?.discloseCurrentState(cause: .userAction)
     }
 

wire-ios/Wire-iOS/Sources/UserInterface/ConversationList/Container/ViewModel/ConversationListViewControllerViewModel+ConversationListContentDelegate.swift

@@ -35,6 +35,10 @@ extension ConversationListViewController.ViewModel: ConversationListContentDeleg
     ) {
         showActionMenu(for: conversation, from: sourceView)
     }
+
+    func conversationListContentControllerDidReload(_ controller: ConversationListContentController) {
+        viewController?.conversationListViewControllerViewModelDidReloadContent(self)
+    }
 }
 
 extension ConversationListViewController.ViewModel {

wire-ios/Wire-iOS/Sources/UserInterface/ConversationList/Container/ViewModel/ConversationListViewControllerViewModel.swift

@@ -58,6 +58,10 @@
         _ viewModel: ConversationListViewController
             .ViewModel
     )
+
+    func conversationListViewControllerViewModelDidReloadContent(
+        _ viewModel: ConversationListViewController.ViewModel
+    )
 }
 
 extension ConversationListViewController {
@@ -154,7 +158,7 @@
 extension ConversationListViewController.ViewModel {
 
     func setupObservers() {
 
         if let userSession = ZMUserSession.shared() {
             userObservationToken = userSession.addUserObserver(self, for: selfUserLegalHoldSubject)
 
@@ -286,7 +290,7 @@
 
 extension ConversationListViewController.ViewModel: UserObserving {
 
     @MainActor
     func userDidChange(_ changeInfo: UserChangeInfo) {
 
         if changeInfo.nameChanged || changeInfo.imageMediumDataChanged || changeInfo
@@ -321,7 +325,7 @@
 
 extension ConversationListViewController.ViewModel: TeamObserver {
 
     @MainActor
     func teamDidChange(_ changeInfo: TeamChangeInfo) {
 
         if changeInfo.imageDataChanged {

wire-ios/Wire-iOS/Sources/UserInterface/ConversationList/ListContent/ConversationListContentController/ConversationListContentController.swift

@@ -301,7 +301,7 @@
         guard let conversation = listViewModel.item(for: indexPath) as? ZMConversation else {
             return nil
         }
 
         let previewProvider: UIContextMenuContentPreviewProvider = {
             ConversationPreviewViewController(
                 conversation: conversation,
@@ -471,6 +471,7 @@
         let reloadClosure = {
             self.collectionView.reloadSections(IndexSet(integer: section))
             self.ensureCurrentSelection()
+            self.contentDelegate?.conversationListContentControllerDidReload(self)
         }
 
         if animated {
@@ -490,6 +491,7 @@
         setData: (C?) -> Void
     ) {
         collectionView.reload(using: stagedChangeset, interrupt: interrupt, setData: setData)
+        contentDelegate?.conversationListContentControllerDidReload(self)
     }
 }
 

wire-ios/Wire-iOS/Sources/UserInterface/ConversationList/ListContent/ConversationListContentDelegate.swift

@@ -19,14 +19,20 @@
 import WireDataModel
 
 protocol ConversationListContentDelegate: AnyObject {
+
     func conversationList(
         _ controller: ConversationListContentController?,
         didSelect conversation: ZMConversation?,
         focusOnView focus: Bool
     )
+
     func conversationListContentController(
         _ controller: ConversationListContentController?,
         wantsActionMenuFor conversation: ZMConversation?,
         fromSourceView sourceView: UIView?
     )
+
+    func conversationListContentControllerDidReload(
+        _ controller: ConversationListContentController
+    )
 }