Pass <Alt> to the application

.github/actions/spell-check/dictionary/apis.txt

@@ -12,6 +12,7 @@ IBind
 IClass
 IComparable
 ICustom
+IDirect
 IExplorer
 IMap
 IObject

src/cascadia/TerminalApp/AppLogic.cpp

@@ -906,20 +906,21 @@ namespace winrt::TerminalApp::implementation
 
     // Method Description:
     // - Implements the F7 handler (per GH#638)
+    // - Implements the Alt handler (per GH#6421)
     // Return value:
-    // - whether F7 was handled
-    bool AppLogic::OnF7Pressed()
+    // - whether the key was handled
+    bool AppLogic::OnGotAKey(const uint32_t vkey, const bool down)
     {
         if (_root)
         {
-            // Manually bubble the OnF7Pressed event up through the focus tree.
+            // Manually bubble the OnAltReleased event up through the focus tree.
             auto xamlRoot{ _root->XamlRoot() };
             auto focusedObject{ Windows::UI::Xaml::Input::FocusManager::GetFocusedElement(xamlRoot) };
             do
             {
-                if (auto f7Listener{ focusedObject.try_as<IF7Listener>() })
+                if (auto keyListener{ focusedObject.try_as<IDirectKeyListener>() })
                 {
-                    if (f7Listener.OnF7Pressed())
+                    if (keyListener.OnGotAKey(vkey, down))
                     {
                         return true;
                     }

src/cascadia/TerminalApp/AppLogic.h

@@ -45,7 +45,7 @@ namespace winrt::TerminalApp::implementation
 
         hstring Title();
         void TitlebarClicked();
-        bool OnF7Pressed();
+        bool OnGotAKey(const uint32_t vkey, const bool down);
 
         void WindowCloseButtonClicked();
 

src/cascadia/TerminalApp/AppLogic.idl

@@ -3,7 +3,7 @@
 
 import "../TerminalPage.idl";
 import "../ShortcutActionDispatch.idl";
-import "../IF7Listener.idl";
+import "../IDirectKeyListener.idl";
 
 namespace TerminalApp
 {
@@ -14,7 +14,7 @@ namespace TerminalApp
         FullscreenMode,
     };
 
-    [default_interface] runtimeclass AppLogic : IF7Listener
+    [default_interface] runtimeclass AppLogic : IDirectKeyListener
     {
         AppLogic();
 

src/cascadia/TerminalApp/IF7Listener.idl → src/cascadia/TerminalApp/IDirectKeyListener.idl

@@ -7,10 +7,9 @@ namespace TerminalApp
     // Instead, we just pin the uuid and include it in both TermControl and App
     // If you update this one, please update the one in TerminalControl\TermControl.idl
     // If you change this interface, please update the guid.
-    // If you press F7 and get a runtime error, go make sure both copies are the same.
+    // If you press F7 or Alt and get a runtime error, go make sure both copies are the same.
     [uuid("339e1a87-5315-4da6-96f0-565549b6472b")]
-    interface IF7Listener
-    {
-        Boolean OnF7Pressed();
+    interface IDirectKeyListener {
+        Boolean OnGotAKey(UInt32 vkey, Boolean down);
     }
 }

src/cascadia/TerminalApp/lib/TerminalAppLib.vcxproj

@@ -201,7 +201,7 @@
   <ItemGroup>
     <!-- If you add idl files here, make sure to include their implementation's
     header in TerminalApp.vcxproj (as well as in this file) -->
-    <Midl Include="../IF7Listener.idl" />
+    <Midl Include="../IDirectKeyListener.idl" />
     <Midl Include="../App.idl">
       <DependentUpon>../App.xaml</DependentUpon>
     </Midl>

src/cascadia/TerminalControl/TermControl.cpp

@@ -683,36 +683,46 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
     }
 
     // Method Description:
-    // - Manually generate an F7 event into the key bindings or terminal.
-    //   This is required as part of GH#638.
+    // - Manually handles key events for certain keys that can't be passed to us
+    //   normally. Namely, the keys we're concerned with are F7 down and Alt up.
     // Return value:
-    // - Whether F7 was handled.
-    bool TermControl::OnF7Pressed()
+    // - Whether the key was handled.
+    bool TermControl::OnGotAKey(const uint32_t vkey, const bool down)
     {
-        bool handled{ false };
-        auto bindings{ _settings.KeyBindings() };
-
         const auto modifiers{ _GetPressedModifierKeys() };
-
-        if (bindings)
-        {
-            handled = bindings.TryKeyChord({
-                modifiers.IsCtrlPressed(),
-                modifiers.IsAltPressed(),
-                modifiers.IsShiftPressed(),
-                VK_F7,
-            });
-        }
-
-        if (!handled)
+        auto handled = false;
+        if (vkey == VK_MENU && !down)
         {
-            // _TrySendKeyEvent pretends it didn't handle F7 for some unknown reason.
-            (void)_TrySendKeyEvent(VK_F7, 0, modifiers, true);
-            // GH#6438: Note that we're _not_ sending the key up here - that'll
-            // get passed through XAML to our KeyUp handler normally.
+            // Manually generate an Alt KeyUp event into the key bindings or terminal.
+            //   This is required as part of GH#6421.
+            (void)_TrySendKeyEvent(VK_MENU, 0, modifiers, false);
             handled = true;
         }
+        else if (vkey == VK_F7 && down)
+        {
+            // Manually generate an F7 event into the key bindings or terminal.
+            //   This is required as part of GH#638.
+            auto bindings{ _settings.KeyBindings() };
+
+            if (bindings)
+            {
+                handled = bindings.TryKeyChord({
+                    modifiers.IsCtrlPressed(),
+                    modifiers.IsAltPressed(),
+                    modifiers.IsShiftPressed(),
+                    VK_F7,
+                });
+            }
 
+            if (!handled)
+            {
+                // _TrySendKeyEvent pretends it didn't handle F7 for some unknown reason.
+                (void)_TrySendKeyEvent(VK_F7, 0, modifiers, true);
+                // GH#6438: Note that we're _not_ sending the key up here - that'll
+                // get passed through XAML to our KeyUp handler normally.
+                handled = true;
+            }
+        }
         return handled;
     }
 

src/cascadia/TerminalControl/TermControl.h

@@ -84,7 +84,7 @@ namespace winrt::Microsoft::Terminal::TerminalControl::implementation
 
         void CreateSearchBoxControl();
 
-        bool OnF7Pressed();
+        bool OnGotAKey(const uint32_t vkey, const bool down);
 
         bool OnMouseWheel(const Windows::Foundation::Point location, const int32_t delta);
 

src/cascadia/TerminalControl/TermControl.idl

@@ -11,13 +11,12 @@ namespace Microsoft.Terminal.TerminalControl
 
     // C++/winrt makes it difficult to share this idl between two projects,
     // Instead, we just pin the uuid and include it in both TermControl and App
-    // If you update this one, please update TerminalApp\IF7Listener.idl.
+    // If you update this one, please update TerminalApp\IDirectKeyListener.idl.
     // If you change this interface, please update the guid.
-    // If you press F7 and get a runtime error, go make sure both copies are the same.
+    // If you press F7 or Alt and get a runtime error, go make sure both copies are the same.
     [uuid("339e1a87-5315-4da6-96f0-565549b6472b")]
-    interface IF7Listener
-    {
-        Boolean OnF7Pressed();
+    interface IDirectKeyListener {
+        Boolean OnGotAKey(UInt32 vkey, Boolean down);
     }
 
     runtimeclass CopyToClipboardEventArgs
@@ -32,7 +31,7 @@ namespace Microsoft.Terminal.TerminalControl
         void HandleClipboardData(String data);
     }
 
-    [default_interface] runtimeclass TermControl : Windows.UI.Xaml.Controls.UserControl, IF7Listener, IMouseWheelListener
+    [default_interface] runtimeclass TermControl : Windows.UI.Xaml.Controls.UserControl, IDirectKeyListener, IMouseWheelListener
     {
         TermControl();
         TermControl(Microsoft.Terminal.Settings.IControlSettings settings, Microsoft.Terminal.TerminalConnection.ITerminalConnection connection);

src/cascadia/WindowsTerminal/AppHost.cpp

@@ -63,11 +63,11 @@ AppHost::~AppHost()
     _app = nullptr;
 }
 
-bool AppHost::OnF7Pressed()
+bool AppHost::OnGotAKey(const uint32_t vkey, const bool down)
 {
     if (_logic)
     {
-        return _logic.OnF7Pressed();
+        return _logic.OnGotAKey(vkey, down);
     }
     return false;
 }

src/cascadia/WindowsTerminal/AppHost.h

@@ -17,7 +17,7 @@ class AppHost
     void AppTitleChanged(const winrt::Windows::Foundation::IInspectable& sender, winrt::hstring newTitle);
     void LastTabClosed(const winrt::Windows::Foundation::IInspectable& sender, const winrt::TerminalApp::LastTabClosedEventArgs& args);
     void Initialize();
-    bool OnF7Pressed();
+    bool OnGotAKey(const uint32_t vkey, const bool down);
 
 private:
     bool _useNonClientArea;

src/cascadia/WindowsTerminal/main.cpp

@@ -77,6 +77,10 @@ static bool _messageIsF7Keypress(const MSG& message)
 {
     return (message.message == WM_KEYDOWN || message.message == WM_SYSKEYDOWN) && message.wParam == VK_F7;
 }
+static bool _messageIsAltKeyup(const MSG& message)
+{
+    return (message.message == WM_KEYUP || message.message == WM_SYSKEYUP) && message.wParam == VK_MENU;
+}
 
 int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
 {
@@ -137,13 +141,26 @@ int __stdcall wWinMain(HINSTANCE, HINSTANCE, LPWSTR, int)
         // been handled we can discard the message before we even translate it.
         if (_messageIsF7Keypress(message))
         {
-            if (host.OnF7Pressed())
+            if (host.OnGotAKey(VK_F7, true))
             {
                 // The application consumed the F7. Don't let Xaml get it.
                 continue;
             }
         }
 
+        // GH#6421 - System XAML will never send an Alt KeyUp event. So, similar
+        // to how we'll steal the F7 KeyDown above, we'll steal the Alt KeyUp
+        // here, and plumb it through.
+        if (_messageIsAltKeyup(message))
+        {
+            // Let's pass <Alt> to the application
+            if (host.OnGotAKey(VK_MENU, false))
+            {
+                // The application consumed the Alt. Don't let Xaml get it.
+                continue;
+            }
+        }
+
         TranslateMessage(&message);
         DispatchMessage(&message);
     }