Showcase checkboxes

Restore 'save changes' exit prompt
Set Runnable to render with dotted line for border
Don't show Arrangement options unless its a container view
Make CheckBox radio style a designable property

Author: tznind

Showcase/Checkboxes.Designer.cs

@@ -0,0 +1,20 @@
+
+//------------------------------------------------------------------------------
+
+//  <auto-generated>
+//      This code was generated by:
+//        TerminalGuiDesigner v2.0.2.0
+//      You can make changes to this file and they will not be overwritten when saving.
+//  </auto-generated>
+// -----------------------------------------------------------------------------
+namespace Showcase {
+    using Terminal.Gui;
+    
+    
+    public partial class Checkboxes {
+        
+        public Checkboxes() {
+            InitializeComponent();
+        }
+    }
+}

Showcase/Checkboxes.cs

@@ -9,7 +9,11 @@ internal class Program
     {
         static void Main(string[] args)
         {
-            Type[] types = [typeof(Menus), typeof(Buttons)];
+            Type[] types = [
+                typeof(Menus),
+                typeof(Buttons),
+                typeof(Checkboxes)
+                ];
 
             using (var app = Application.Create())
             {

Showcase/Program.cs

@@ -610,7 +610,11 @@ private IEnumerable<Property> LoadDesignableProperties()
 
         yield return this.CreateSuppressedProperty(nameof(this.View.Visible), true);
 
-        yield return this.CreateSuppressedProperty(nameof(this.View.Arrangement), ViewArrangement.Fixed);
+        if (this.View.IsContainerView())
+        {
+            // Don't offer to make checkboxes etc Resizeable/Overlapped etc
+            yield return this.CreateSuppressedProperty(nameof(this.View.Arrangement), ViewArrangement.Fixed);
+        }
 
         yield return this.CreateSuppressedProperty(nameof(View.CanFocus), true);
 
@@ -715,6 +719,7 @@ private IEnumerable<Property> LoadDesignableProperties()
         if (this.View is CheckBox)
         {
             yield return this.CreateProperty(nameof(CheckBox.Value));
+            yield return this.CreateProperty(nameof(CheckBox.RadioStyle));
         }
         if (this.View is ColorPicker cp)
         {

src/Design.cs

@@ -200,6 +200,7 @@ public static bool IsContainerView(this View v)
 
         // TODO: are there any others?
         return
+            v.GetType() == typeof(Runnable) ||
             v is FrameView ||
             v is Window ||
             type == typeof(View) || type.Name.Equals("ContentView");
@@ -213,11 +214,6 @@ v is Window ||
     /// <returns>True if no visible border and <see cref="ViewExtensions.IsContainerView(View)"/>.</returns>
     public static bool IsBorderlessContainerView(this View v)
     {
-        if (v is Runnable)
-        {
-            return false;
-        }
-
         if (v.IsContainerView() && v.HasNoBorderProperty())
         {
             return true;