Add the same unsaved changes alerts that Android has. (#4803)

* Add an alert to Discard or Save when there are unsaved changes on the RoomDetailsEditScreen.

* Add an alert to Discard or Save when there are unsaved changes on the UserDetailsEditScreen.

* Add an alert to Discard or Save when there are unsaved changes on the SecurityAndPrivacyScreen.

* Update strings.

ElementX/Sources/Screens/SecurityAndPrivacyScreen/SecurityAndPrivacyScreenCoordinator.swift

@@ -18,6 +18,7 @@ struct SecurityAndPrivacyScreenCoordinatorParameters {
 
 enum SecurityAndPrivacyScreenCoordinatorAction {
     case displayEditAddressScreen
+    case dismiss
 }
 
 final class SecurityAndPrivacyScreenCoordinator: CoordinatorProtocol {
@@ -45,6 +46,8 @@ final class SecurityAndPrivacyScreenCoordinator: CoordinatorProtocol {
             switch action {
             case .displayEditAddressScreen:
                 actionsSubject.send(.displayEditAddressScreen)
+            case .dismiss:
+                actionsSubject.send(.dismiss)
             }
         }
         .store(in: &cancellables)

ElementX/Sources/Screens/SecurityAndPrivacyScreen/SecurityAndPrivacyScreenModels.swift

@@ -10,6 +10,7 @@ import Foundation
 
 enum SecurityAndPrivacyScreenViewModelAction {
     case displayEditAddressScreen
+    case dismiss
 }
 
 struct SecurityAndPrivacyScreenViewState: BindableState {
@@ -188,9 +189,11 @@ enum SecurityAndPrivacyRoomAccessType: Equatable {
 
 enum SecurityAndPrivacyAlertType {
     case enableEncryption
+    case unsavedChanges
 }
 
 enum SecurityAndPrivacyScreenViewAction {
+    case cancel
     case save
     case tryUpdatingEncryption(Bool)
     case editAddress

ElementX/Sources/Screens/SecurityAndPrivacyScreen/SecurityAndPrivacyScreenViewModel.swift

@@ -62,10 +62,10 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
         MXLog.info("View model: received view action: \(viewAction)")
         
         switch viewAction {
+        case .cancel:
+            showUnsavedChangesAlert() // The cancel button is only shown when there are unsaved changes.
         case .save:
-            Task {
-                await saveDesiredSettings()
-            }
+            Task { await saveDesiredSettings() }
         case .tryUpdatingEncryption(let updatedValue):
             if updatedValue {
                 state.bindings.alertInfo = .init(id: .enableEncryption,
@@ -168,12 +168,19 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
         }
     }
     
-    private func saveDesiredSettings() async {
+    private func showUnsavedChangesAlert() {
+        state.bindings.alertInfo = .init(id: .unsavedChanges,
+                                         title: L10n.dialogUnsavedChangesTitle,
+                                         message: L10n.dialogUnsavedChangesDescription,
+                                         primaryButton: .init(title: L10n.actionSave) { Task { await self.saveDesiredSettings(shouldDismiss: true) } },
+                                         secondaryButton: .init(title: L10n.actionDiscard, role: .cancel) { self.actionsSubject.send(.dismiss) })
+    }
+    
+    private func saveDesiredSettings(shouldDismiss: Bool = false) async {
         showLoadingIndicator()
+        defer { hideLoadingIndicator() }
         
-        defer {
-            hideLoadingIndicator()
-        }
+        var hasFailures = false
         
         if state.currentSettings.isEncryptionEnabled != state.bindings.desiredSettings.isEncryptionEnabled {
             switch await roomProxy.enableEncryption() {
@@ -181,6 +188,7 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
                 state.currentSettings.isEncryptionEnabled = state.bindings.desiredSettings.isEncryptionEnabled
             case .failure:
                 userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+                hasFailures = true
             }
         }
         
@@ -190,6 +198,7 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
                 state.currentSettings.historyVisibility = state.bindings.desiredSettings.historyVisibility
             case .failure:
                 userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+                hasFailures = true
             }
         }
         
@@ -205,6 +214,7 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
                 state.currentSettings.accessType = state.bindings.desiredSettings.accessType
             case .failure:
                 userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+                hasFailures = true
             }
         }
         
@@ -216,8 +226,13 @@ class SecurityAndPrivacyScreenViewModel: SecurityAndPrivacyScreenViewModelType,
                 state.currentSettings.isVisibileInRoomDirectory = state.bindings.desiredSettings.isVisibileInRoomDirectory
             case .failure:
                 userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+                hasFailures = true
             }
         }
+        
+        if shouldDismiss, !hasFailures {
+            actionsSubject.send(.dismiss)
+        }
     }
     
     private func handleSelectedSpaceMembersAccess() {

ElementX/Sources/Screens/SecurityAndPrivacyScreen/View/SecurityAndPrivacyScreen.swift

@@ -39,6 +39,7 @@ struct SecurityAndPrivacyScreen: View {
         .compoundList()
         .navigationBarTitleDisplayMode(.inline)
         .navigationTitle(L10n.screenSecurityAndPrivacyTitle)
+        .navigationBarBackButtonHidden(!context.viewState.isSaveDisabled)
         .toolbar { toolbar }
         .alert(item: $context.alertInfo)
     }
@@ -185,6 +186,14 @@ struct SecurityAndPrivacyScreen: View {
     
     @ToolbarContentBuilder
     private var toolbar: some ToolbarContent {
+        ToolbarItem(placement: .cancellationAction) {
+            if !context.viewState.isSaveDisabled {
+                Button(L10n.actionCancel) {
+                    context.send(viewAction: .cancel)
+                }
+            }
+        }
+        
         ToolbarItem(placement: .confirmationAction) {
             Button(L10n.actionSave) {
                 context.send(viewAction: .save)