Back navigation and shell improvements.

2026-03-24 18:05:09 +01:00
parent d699818c6f
commit 27c90d2f89
10 changed files with 96 additions and 86 deletions
@@ -219,6 +219,9 @@ public class NavigationService : NavigationServiceBase, INavigationService
    public bool ChangeApplicationMode(WinoApplicationMode mode)
        => ExecuteOnNavigationThread(() => ChangeApplicationModeInternal(mode));

+    public bool CanGoBack()
+        => ExecuteOnNavigationThread(CanGoBackInternal);
+
    private bool ChangeApplicationModeInternal(WinoApplicationMode mode, object? activationParameter = null)
    {
        var coreFrame = GetCoreFrameInternal(NavigationReferenceFrame.ShellFrame);
@@ -333,7 +336,6 @@ public class NavigationService : NavigationServiceBase, INavigationService
                    if (innerShellFrame.CanGoBack && lastBackStackEntry?.SourcePageType == pageType)
                    {
                        innerShellFrame.GoBack();
-                        UpdateCurrentModeBackStackState(innerShellFrame);
                        WeakReferenceMessenger.Default.Send(loadCalendarMessage);
                        return true;
                    }
@@ -495,7 +497,7 @@ public class NavigationService : NavigationServiceBase, INavigationService

        if (navigationResult)
        {
-            UpdateCurrentModeBackStackState(frame);
+            return true;
        }

        return navigationResult;
@@ -522,15 +524,13 @@ public class NavigationService : NavigationServiceBase, INavigationService
        var currentApplicationMode = _statePersistanceService.ApplicationMode;

        if (currentApplicationMode == WinoApplicationMode.Settings &&
-            _statePersistanceService.HasCurrentModeBackStack)
+            innerShellFrame?.Content is SettingsPage settingsPage)
        {
-            WeakReferenceMessenger.Default.Send(new BackBreadcrumNavigationRequested(slideEffect));
-            return;
-        }
+            if (settingsPage.CanNavigateBack)
+            {
+                WeakReferenceMessenger.Default.Send(new BackBreadcrumNavigationRequested(slideEffect));
+            }

-        if (currentApplicationMode == WinoApplicationMode.Settings &&
-            innerShellFrame?.Content is SettingsPage)
-        {
            return;
        }

@@ -544,7 +544,6 @@ public class NavigationService : NavigationServiceBase, INavigationService
            if (innerShellFrame?.CanGoBack == true)
            {
                innerShellFrame.GoBack();
-                UpdateCurrentModeBackStackState(innerShellFrame);
            }
            else if (innerShellFrame != null && innerShellFrame.Content?.GetType() != typeof(CalendarPage))
            {
@@ -560,16 +559,11 @@ public class NavigationService : NavigationServiceBase, INavigationService
            {
                // Mail mode: Clear selections and dispose rendering frame
                _statePersistanceService.IsReadingMail = false;
-                _statePersistanceService.HasCurrentModeBackStack = false;

                WeakReferenceMessenger.Default.Send(new ClearMailSelectionsRequested());
                WeakReferenceMessenger.Default.Send(new DisposeRenderingFrameRequested());
            }
        }
-        else
-        {
-            UpdateCurrentModeBackStackState(innerShellFrame);
-        }
    }

    private void ResetCurrentModeBackStackState()
@@ -581,17 +575,6 @@ public class NavigationService : NavigationServiceBase, INavigationService
            innerShellFrame.BackStack.Clear();
            innerShellFrame.ForwardStack.Clear();
        }
-
-        _statePersistanceService.HasCurrentModeBackStack = false;
-    }
-
-    private void UpdateCurrentModeBackStackState(Frame? innerShellFrame)
-    {
-        if (_statePersistanceService.ApplicationMode == WinoApplicationMode.Settings)
-            return;
-
-        _statePersistanceService.HasCurrentModeBackStack = _statePersistanceService.ApplicationMode == WinoApplicationMode.Calendar &&
-                                                           innerShellFrame?.CanGoBack == true;
    }

    private void PruneInnerShellBackStackForMode(Frame frame, WinoApplicationMode mode)
@@ -636,7 +619,33 @@ public class NavigationService : NavigationServiceBase, INavigationService

        frame.BackStack.Clear();
        frame.ForwardStack.Clear();
-        UpdateCurrentModeBackStackState(frame);
+    }
+
+    private bool CanGoBackInternal()
+    {
+        var innerShellFrame = GetCoreFrameInternal(NavigationReferenceFrame.InnerShellFrame);
+
+        return _statePersistanceService.ApplicationMode switch
+        {
+            WinoApplicationMode.Mail => _statePersistanceService.IsReadingMail && _statePersistanceService.IsReaderNarrowed,
+            WinoApplicationMode.Settings => innerShellFrame?.Content is SettingsPage settingsPage && settingsPage.CanNavigateBack,
+            WinoApplicationMode.Calendar or WinoApplicationMode.Contacts => HasModeScopedBackStack(innerShellFrame, _statePersistanceService.ApplicationMode),
+            _ => false
+        };
+    }
+
+    private bool HasModeScopedBackStack(Frame? innerShellFrame, WinoApplicationMode mode)
+    {
+        if (innerShellFrame == null || innerShellFrame.BackStack.Count == 0)
+            return false;
+
+        for (int i = innerShellFrame.BackStack.Count - 1; i >= 0; i--)
+        {
+            if (IsPageTypeAllowedInMode(mode, innerShellFrame.BackStack[i].SourcePageType))
+                return true;
+        }
+
+        return false;
    }

    // Standalone EML viewer.