Add focused state for DropDownButton and reduces the icon width of the dropdown model button

Author: LeafShi1

src/System.Windows.Forms/PublicAPI.Unshipped.txt

@@ -0,0 +1 @@
+System.Windows.Forms.VisualStyles.ComboBoxState.Focused = 5 -> System.Windows.Forms.VisualStyles.ComboBoxState

src/System.Windows.Forms/System/Windows/Forms/Controls/PropertyGrid/PropertyGridInternal/DropDownButton.cs

@@ -83,14 +83,22 @@ protected override void OnPaint(PaintEventArgs pevent)
     {
         ComboBoxState state = ComboBoxState.Normal;
 
-        if (MouseIsDown)
+        if (!Enabled)
+        {
+            state = ComboBoxState.Disabled;
+        }
+        else if (MouseIsDown)
         {
             state = ComboBoxState.Pressed;
         }
         else if (MouseIsOver)
         {
             state = ComboBoxState.Hot;
         }
+        else if (Focused)
+        {
+            state = ComboBoxState.Focused;
+        }
 
         base.OnPaint(pevent);
 
@@ -101,6 +109,7 @@ protected override void OnPaint(PaintEventArgs pevent)
                 ComboBoxState.Disabled => ModernControlButtonState.Disabled,
                 ComboBoxState.Hot => ModernControlButtonState.Hover,
                 ComboBoxState.Pressed => ModernControlButtonState.Pressed,
+                ComboBoxState.Focused => ModernControlButtonState.Focused,
                 _ => ModernControlButtonState.Normal
             };
 

src/System.Windows.Forms/System/Windows/Forms/Rendering/ControlPaint.ModernControlButtonState.cs

@@ -10,6 +10,7 @@ internal enum ModernControlButtonState
         Normal,
         Disabled,
         Pressed,
-        Hover
+        Hover,
+        Focused
     }
 }

src/System.Windows.Forms/System/Windows/Forms/Rendering/ControlPaint_ModernControlButtonRenderer.cs

@@ -91,6 +91,8 @@ internal static void DrawModernControlButton(
 
             bool hasRoundedBorder = (button & ModernControlButtonStyle.RoundedBorder) != 0;
 
+            bool isFocused = state == ModernControlButtonState.Focused;
+
             // Draw background
             using (var backgroundBrush = backgroundColor.GetCachedSolidBrushScope())
             {
@@ -121,6 +123,14 @@ internal static void DrawModernControlButton(
                 }
             }
 
+            if (isFocused)
+            {
+                // Draw focus rectangle
+                Rectangle focusRect = bounds;
+                focusRect.Inflate(-1, -1); // Deflate to avoid drawing over the border
+                DrawFocusRectangle(graphics, focusRect, Color.Empty, backgroundColor);
+            }
+
             // Draw the content
             ModernControlButtonStyle contentType = button
                 & ~(ModernControlButtonStyle.SingleBorder
@@ -280,7 +290,7 @@ private static void DrawEllipseSymbol(Graphics graphics, Brush brush, int center
     {
         // Calculate dot size as a proportion of button height
         int minDimension = Math.Min(bounds.Width, bounds.Height);
-        int dotSize = Math.Max(1, (int)(minDimension * 0.15 * ContentScaleFactor));
+        int dotSize = Math.Max(1, (int)(minDimension * 0.1 * ContentScaleFactor));
 
         // Calculate proportional spacing
         int spacing = Math.Max(1, dotSize / 2);
@@ -310,7 +320,7 @@ private static void DrawEllipseSymbol(Graphics graphics, Brush brush, int center
     private static void DrawOpenDropDownChevron(Graphics graphics, Brush brush, int centerX, int centerY, int size)
     {
         // Calculate chevron dimensions proportionally
-        int chevronWidth = size + (size / 2);
+        int chevronWidth = size;
         int chevronHeight = (size * 2) / 3;
 
         // Stroke thickness scales with size

src/System.Windows.Forms/System/Windows/Forms/VisualStyles/ComboBoxState.cs

@@ -8,5 +8,6 @@ public enum ComboBoxState
     Normal = 1,
     Hot = 2,
     Pressed = 3,
-    Disabled = 4
+    Disabled = 4,
+    Focused = 5,
 }