Fixes #3691. Adds Popover

Terminal.Gui/Application/Application.Driver.cs

@@ -8,6 +8,7 @@ public static partial class Application // Driver abstractions
     /// <summary>Gets the <see cref="ConsoleDriver"/> that has been selected. See also <see cref="ForceDriver"/>.</summary>
     public static ConsoleDriver? Driver { get; internal set; }
 
+    // BUGBUG: Force16Colors should be nullable.
     /// <summary>
     ///     Gets or sets whether <see cref="Application.Driver"/> will be forced to output only the 16 colors defined in
     ///     <see cref="ColorName16"/>. The default is <see langword="false"/>, meaning 24-bit (TrueColor) colors will be output
@@ -16,6 +17,7 @@ public static partial class Application // Driver abstractions
     [SerializableConfigurationProperty (Scope = typeof (SettingsScope))]
     public static bool Force16Colors { get; set; }
 
+    // BUGBUG: ForceDriver should be nullable.
     /// <summary>
     ///     Forces the use of the specified driver (one of "fake", "ansi", "curses", "net", or "windows"). If not
     ///     specified, the driver is selected based on the platform.

Terminal.Gui/Application/Application.Keyboard.cs

@@ -20,7 +20,14 @@
             return true;
         }
 
-        if (Top is null)
+        View? top = Top;
+
+        if (Popover is { Visible: true })
+        {
+            top = Popover;
+        }
+
+        if (top is null)
         {
             foreach (Toplevel topLevel in TopLevels.ToList ())
             {
@@ -37,7 +44,7 @@
         }
         else
         {
             if (Top.NewKeyDownEvent (key))
             {
                 return true;
             }
@@ -49,6 +56,11 @@
         {
             if (binding.Value.BoundView is { })
             {
+                if (!binding.Value.BoundView.Enabled)
+                {
+                    return false;
+                }
+
                 bool? handled = binding.Value.BoundView?.InvokeCommands (binding.Value.Commands, binding.Key, binding.Value);
 
                 if (handled != null && (bool)handled)
@@ -164,6 +176,12 @@
                     Command.Quit,
                     static () =>
                     {
+                        if (Popover is {Visible: true})
+                        {
+                            Popover.Visible = false;
+
+                            return true;
+                        }
                         RequestStop ();
 
                         return true;

Terminal.Gui/Application/Application.Mouse.cs

@@ -1,5 +1,6 @@
 #nullable enable
 using System.ComponentModel;
+using System.Diagnostics;
 
 namespace Terminal.Gui;
 
@@ -165,16 +166,31 @@ internal static void RaiseMouseEvent (MouseEventArgs mouseEvent)
             return;
         }
 
+        if (Popover is { Visible: true }
+            && View.IsInHierarchy (Popover, deepestViewUnderMouse, includeAdornments: true) is false
+            && (mouseEvent.Flags.HasFlag (MouseFlags.Button1Pressed)
+                || mouseEvent.Flags.HasFlag (MouseFlags.Button2Pressed)
+                || mouseEvent.Flags.HasFlag (MouseFlags.Button3Pressed)))
+        {
+
+            Popover.Visible = false;
+
+            // Recurse once
+            RaiseMouseEvent (mouseEvent);
+
+            return;
+        }
+
         if (HandleMouseGrab (deepestViewUnderMouse, mouseEvent))
         {
             return;
         }
 
         WantContinuousButtonPressedView = deepestViewUnderMouse switch
-        {
-            { WantContinuousButtonPressed: true } => deepestViewUnderMouse,
-            _ => null
-        };
+                                          {
+                                              { WantContinuousButtonPressed: true } => deepestViewUnderMouse,
+                                              _ => null
+                                          };
 
         // May be null before the prior condition or the condition may set it as null.
         // So, the checking must be outside the prior condition.
@@ -213,6 +229,7 @@ internal static void RaiseMouseEvent (MouseEventArgs mouseEvent)
         else
         {
             // The mouse was outside any View's Viewport.
+            Debug.Fail ("this should not happen.");
 
             // Debug.Fail ("This should never happen. If it does please file an Issue!!");
 

Terminal.Gui/Application/Application.Popover.cs

@@ -0,0 +1,87 @@
+#nullable enable
+namespace Terminal.Gui;
+
+public static partial class Application // Popover handling
+{
+    private static View? _popover;
+
+    /// <summary>Gets or sets the Application Popover View.</summary>
+    /// <remarks>
+    ///     <para>
+    ///         To show or hide the Popover, set it's <see cref="View.Visible"/> property.
+    ///     </para>
+    /// </remarks>
+    public static View? Popover
+    {
+        get => _popover;
+        set
+        {
+            if (_popover == value)
+            {
+                return;
+            }
+
+            if (_popover is { })
+            {
+                _popover.Visible = false;
+                _popover.VisibleChanging -= PopoverVisibleChanging;
+            }
+
+            _popover = value;
+
+            if (_popover is { })
+            {
+                if (!_popover.IsInitialized)
+                {
+                    _popover.BeginInit ();
+                    _popover.EndInit ();
+                }
+
+                _popover.Arrangement |= ViewArrangement.Overlapped;
+
+                if (_popover.ColorScheme is null)
+                {
+                    _popover.ColorScheme = Top?.ColorScheme;
+                }
+
+                _popover.SetRelativeLayout (Screen.Size);
+
+                _popover.VisibleChanging += PopoverVisibleChanging;
+            }
+        }
+    }
+
+    private static void PopoverVisibleChanging (object? sender, CancelEventArgs<bool> e)
+    {
+        if (Popover is null)
+        {
+            return;
+        }
+
+        if (e.NewValue)
+        {
+            Popover.Arrangement |= ViewArrangement.Overlapped;
+
+            Popover.ColorScheme ??= Top?.ColorScheme;
+
+            View.GetLocationEnsuringFullVisibility (
+                                                    Popover,
+                                                    Popover.Frame.X,
+                                                    Popover.Frame.Y,
+                                                    out int nx,
+                                                    out int ny);
+
+            Popover.X = nx;
+            Popover.Y = ny;
+
+            Popover.SetRelativeLayout (Screen.Size);
+
+            if (Top is { })
+            {
+                Top.HasFocus = false;
+            }
+
+            Popover?.SetFocus ();
+        }
+    }
+}

Terminal.Gui/Application/Application.Run.cs

@@ -499,6 +499,13 @@ public static void Refresh ()
             tl.Draw ();
         }
 
+        if (Popover is { LayoutNeeded: true })
+        {
+            Popover.LayoutSubviews ();
+        }
+
+        Popover?.Draw ();
+
         Driver!.Refresh ();
     }
 
@@ -667,6 +674,11 @@ public static void End (RunState runState)
 
         _cachedRunStateToplevel = runState.Toplevel;
 
+        if (Popover is { })
+        {
+            Popover = null;
+        }
+
         runState.Toplevel = null;
         runState.Dispose ();
 

Terminal.Gui/Application/Application.cs

@@ -167,6 +167,8 @@ internal static void ResetState (bool ignoreDisposed = false)
         Top = null;
         _cachedRunStateToplevel = null;
 
+        Popover = null;
+
         // MainLoop stuff
         MainLoop?.Dispose ();
         MainLoop = null;

Terminal.Gui/Application/ApplicationNavigation.cs

@@ -31,7 +31,7 @@
     {
         return _focused;
 
         if (_focused is { CanFocus: true, HasFocus: true })
         {
             return _focused;
         }
@@ -85,6 +85,10 @@
     /// </remarks>
     internal void SetFocused (View? value)
     {
+        if (value is null)
+        {
+
+        }
         if (_focused == value)
         {
             return;
@@ -113,6 +117,10 @@
     /// </returns>
     public bool AdvanceFocus (NavigationDirection direction, TabBehavior? behavior)
     {
+        if (Application.Popover is { Visible: true })
+        {
+            return Application.Popover.AdvanceFocus (direction, behavior);
+        }
         return Application.Top is { } && Application.Top.AdvanceFocus (direction, behavior);
     }
 }

Terminal.Gui/Drawing/Glyphs.cs

@@ -20,6 +20,11 @@
 /// </remarks>
 public class GlyphDefinitions
 {
+    // IMPORTANT: If you change these, make sure to update the ./Resources/config.json file as
+    // IMPORTANT: it is the source of truth for the default glyphs at runtime.
+    // IMPORTANT: Configuration Manager test SaveDefaults uses this class to generate the default config file
+    // IMPORTANT: in ./UnitTests/bin/Debug/netX.0/config.json
+
     /// <summary>File icon.  Defaults to ☰ (Trigram For Heaven)</summary>
     public Rune File { get; set; } = (Rune)'☰';