Lazy load the states of GraphingMode Category

src/CalcViewModel/Common/NavCategory.cpp

@@ -47,44 +47,53 @@ static constexpr int CURRENCY_ID = 16;
 static constexpr int GRAPHING_ID = 17;
 // ^^^ THESE CONSTANTS SHOULD NEVER CHANGE ^^^
 
-wchar_t* towchar_t(int number)
+namespace
 {
+    Platform::Agile<Windows::System::User^> CurrentUser;
+    std::mutex GraphingModeCheckMutex;
+
+    wchar_t* towchar_t(int number)
+    {
         auto wstr = std::to_wstring(number);
         return _wcsdup(wstr.c_str());
-}
+    }
 
-bool IsGraphingModeAvailable()
+    bool IsGraphingModeAvailable()
-{
+    {
         static bool supportGraph = Windows::Foundation::Metadata::ApiInformation::IsMethodPresent("Windows.UI.Text.RichEditTextDocument", "GetMath");
         return supportGraph;
+    }
+
+    bool IsGraphingModeEnabled()
+    {
+        static bool isChecked = false;
+        static bool isEnabled = false;
+
+        std::scoped_lock<std::mutex> lock(GraphingModeCheckMutex);
+        if (isChecked)
+        {
+            return isEnabled;
+        }
+        else
+        {
+            if (IsGraphingModeAvailable())
+            {
+                auto namedPolicyData = NamedPolicy::GetPolicyFromPathForUser(
+                    CurrentUser.Get(),
+                    L"Education",
+                    L"AllowGraphingCalculator");
+                isEnabled = namedPolicyData->GetBoolean();
+            }
+            else
+            {
+                isEnabled = false;
+            }
+            isChecked = true;
+            return isEnabled;
+        }
+    }
 }
 
-Box<bool> ^ _isGraphingModeEnabledCached = nullptr;
-bool IsGraphingModeEnabled(User ^ currentUser = nullptr)
-{
-    if (!IsGraphingModeAvailable())
-    {
-        return false;
-    }
-
-    if (_isGraphingModeEnabledCached != nullptr)
-    {
-        return _isGraphingModeEnabledCached->Value;
-    }
-
-    if (!currentUser)
-    {
-        return true;
-    }
-
-    auto namedPolicyData = NamedPolicy::GetPolicyFromPathForUser(currentUser, L"Education", L"AllowGraphingCalculator");
-    _isGraphingModeEnabledCached = namedPolicyData->GetBoolean() == true;
-
-    return _isGraphingModeEnabledCached->Value;
-}
-
-
-Platform::Agile<Windows::System::User ^> NavCategoryStates::_currentUser;
 
 // The order of items in this list determines the order of items in the menu.
 static std::vector<NavCategoryInitializer> s_categoryManifest = [] {
@@ -280,36 +289,6 @@ static std::vector<NavCategoryInitializer> s_categoryManifest = [] {
     return res;
 }();
 
-void NavCategory::InitializeCategoryManifest(User ^ user)
-{
-    //int i = 0;
-    //for (NavCategoryInitializer category : s_categoryManifest)
-    //{
-    //    if (category.viewMode == ViewMode::Graphing)
-    //    {
-    //        auto navCatInit = s_categoryManifest.begin();
-    //        std::advance(navCatInit, i);
-    //        (*navCatInit).isEnabled = IsGraphingModeEnabled(user);
-    //        break;
-    //    }
-    //    else
-    //    {
-    //        i++;
-    //    }
-    //}
-}
-
-
-void NavCategory::UpdateGraphingModelManifest(Windows::System::User ^ user)
-{
-    static bool isEnabled = IsGraphingModeEnabled(user);
-    std::find_if(
-        s_categoryManifest.begin(),
-        s_categoryManifest.end(),
-        [](const auto& category) { return category.viewMode == ViewMode::Graphing;})
-        ->isEnabled = isEnabled;
-}
-
 bool NavCategory::IsCalculatorViewMode(ViewMode mode)
 {
     // Historically, Calculator modes are Standard, Scientific, and Programmer.
@@ -379,7 +358,8 @@ NavCategoryGroup::NavCategoryGroup(const NavCategoryGroupInitializer& groupIniti
 
 void NavCategoryStates::SetCurrentUser(Windows::System::User^ user)
 {
-    _currentUser = user;
+    std::scoped_lock<std::mutex> lock(GraphingModeCheckMutex);
+    CurrentUser = user;
 }
 
 IObservableVector<NavCategoryGroup ^> ^ NavCategoryStates::CreateMenuOptions()
@@ -578,11 +558,16 @@ bool NavCategoryStates::IsValidViewMode(ViewMode mode)
 
 bool NavCategoryStates::IsViewModeEnabled(ViewMode mode)
 {
-    const auto& citer = find_if(
+    if (mode == ViewMode::Graphing)
-        cbegin(s_categoryManifest),
+    {
-        cend(s_categoryManifest),
+        return IsGraphingModeEnabled();
+    }
+    else
+    {
+        return std::any_of(
+            s_categoryManifest.cbegin(),
+            s_categoryManifest.cend(),
             [mode](const auto& initializer) { return initializer.viewMode == mode && initializer.isEnabled; });
-
+    }
-    return citer != s_categoryManifest.cend();
 }
 

src/CalcViewModel/Common/NavCategory.h

@@ -99,7 +99,7 @@ namespace CalculatorApp::ViewModel
             PROPERTY_R(ViewMode, Mode);
             PROPERTY_R(Platform::String ^, AccessKey);
             PROPERTY_R(bool, SupportsNegative);
-            PROPERTY_R(bool, IsEnabled);
+            PROPERTY_RW(bool, IsEnabled);
 
             property Platform::String
                 ^ AutomationId { Platform::String ^ get() { return m_Mode.ToString(); } }
@@ -109,9 +109,6 @@ namespace CalculatorApp::ViewModel
             static bool IsDateCalculatorViewMode(ViewMode mode);
             static bool IsConverterViewMode(ViewMode mode);
 
-            static void InitializeCategoryManifest(Windows::System::User ^ user);
-            static void UpdateGraphingModelManifest(Windows::System::User ^ user);
-
             internal : NavCategory(
                            Platform::String ^ name,
                            Platform::String ^ automationName,
@@ -181,9 +178,6 @@ namespace CalculatorApp::ViewModel
             // Virtual key related
             static ViewMode GetViewModeForVirtualKey(MyVirtualKey virtualKey);
             static void GetCategoryAcceleratorKeys(Windows::Foundation::Collections::IVector<MyVirtualKey> ^ resutls);
-
-        private:
-            static Platform::Agile<Windows::System::User ^> _currentUser;
         };
     }
 }

src/Calculator/App.xaml.cs

@@ -19,6 +19,7 @@ using Windows.ApplicationModel.Activation;
 using Windows.ApplicationModel.Core;
 using Windows.Foundation;
 using Windows.Storage;
+using Windows.System;
 using Windows.UI.Core;
 using Windows.UI.StartScreen;
 using Windows.UI.ViewManagement;
@@ -86,6 +87,10 @@ namespace CalculatorApp
                 m_preLaunched = true;
             }
             NavCategoryStates.SetCurrentUser(args.User);
+
+            // It takes time to check GraphingMode at the 1st time. So, do it in a background thread
+            Task.Run(() => NavCategoryStates.IsViewModeEnabled(ViewMode.Graphing));
+
             OnAppLaunch(args, args.Arguments);
         }
 
@@ -411,7 +416,7 @@ namespace CalculatorApp
 
                 foreach (NavCategory option in calculatorOptions.Categories)
                 {
-                    if (!option.IsEnabled)
+                    if (!NavCategoryStates.IsViewModeEnabled(option.Mode))
                     {
                         continue;
                     }

src/Calculator/Views/MainPage.xaml.cs

@@ -147,6 +147,22 @@ namespace CalculatorApp
                 NavViewCategoriesSource.Clear();
                 NavViewCategoriesSource = ExpandNavViewCategoryGroups(Model.Categories);
             };
+
+            _ = Window.Current.Dispatcher.RunAsync(CoreDispatcherPriority.Low, () =>
+            {
+                var graphCategory = (NavCategory)NavViewCategoriesSource.Find(x =>
+                {
+                    if(x is NavCategory category)
+                    {
+                        return category.Mode == ViewMode.Graphing;
+                    }
+                    else
+                    {
+                        return false;
+                    }
+                });
+                graphCategory.IsEnabled = NavCategoryStates.IsViewModeEnabled(ViewMode.Graphing);
+            });
         }
 
         private List<object> ExpandNavViewCategoryGroups(IEnumerable<NavCategoryGroup> groups)