UI catalog (#387)

* key down/up support

* line endings?

* line endings

* KeyDown/Up support

* line endings

* line endings

* Revert "Drop NuGet restore"

This reverts commit 5c7a0d05f0.

* Revert "Revert "Drop NuGet restore""

This reverts commit 2dc5fce865.

* updated demo

* defined styles

* Smarter StatusBar bottom tracking.

* Prepping for https://github.com/migueldeicaza/gui.cs/issues/376

* Oops.

* Fixed StatusBar 'snap to bottom'

* line endings

* Revert "Fixed StatusBar 'snap to bottom'"

This reverts commit 9a91c957e2.

* started UICatalog project

* Initial working POC.

* Fix newlines

* merge

* textalignment demo tweaks

* textalignment demo tweaks

* Unicode Menu Scenario

* not sure why this keeps changing

* re-added project to .sln file

* re-enabled status bar

* moved scenarios to dir

* building a dim and pos demo

* terminal.sln

* progress...barely

* fixed exit

* progress with some underlying fixes to Label

* added readme

* fixes build issue

* launch

* made default colors readable on Windows

* major UI Catalog upgrade

* added more demos and updated readme

* refactored and added more tests

* added ref to Issue #437

* added OnKeyUp support to Curses and Net drivers

* more tweaks - grab PR #438 first

* Added a OpenSelectedItem event to the ListView #429

* updates

* moved KeyUpHandler out of special ESC stuff

* more tweaks & improvements

* testing top window bug

* supported OpenSelectedItem

* lots of updates

* fixed regression, fixed #444

* better button scenario

* tweaks

* add Ready event to Toplevel

* dotfx .gitignroe

* ready for ready

* updated colors based on feedback; consolodated config code

* tweaked readme

* readme

* Added Editor demonstrating TextView

* Added Editor demonstrating TextView

* added hexeditor scenario

Co-authored-by: Miguel de Icaza <miguel@gnome.org>
Co-authored-by: BDisp <bd.bdisp@gmail.com>

UICatalog/Scenario.cs

@@ -0,0 +1,181 @@
+using NStack;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Terminal.Gui;
+
+namespace UICatalog {
+	/// <summary>
+	/// Base class for each demo/scenario. To define a new sceanrio simply
+	/// 
+	/// 1) declare a class derived from Scenario,
+	/// 2) Set Name and Description as appropriate using [ScenarioMetadata] attribute
+	/// 3) Set one or more categories with the [ScenarioCategory] attribute
+	/// 4) Implement Setup.
+	/// 5) Optionally, implement Run.
+	/// 
+	/// The Main program uses reflection to find all sceanarios and adds them to the
+	/// ListViews. Press ENTER to run the selected sceanrio. Press CTRL-Q to exit it.
+	/// </summary>
+	public class Scenario {
+		/// <summary>
+		/// The Top level for the Scenario. This should be set to `Application.Top` in most cases.
+		/// </summary>
+		public Toplevel Top { get; set; }
+
+		/// <summary>
+		/// </summary>
+		public Window Win { get; set; }
+
+		/// <summary>
+		/// Helper that provides the default Window implementation with a frame and 
+		/// label showing the name of the Scenario and logic to exit back to 
+		/// the Scenario picker UI.
+		/// Override Init to provide any `Toplevel` behavior needed.
+		/// </summary>
+		/// <param name="top"></param>
+		public virtual void Init(Toplevel top)
+		{
+			Top = top;
+			Win = new Window ($"CTRL-Q to Close - Scenario: {GetName ()}") {
+				X = 0,
+				Y = 0,
+				Width = Dim.Fill (),
+				Height = Dim.Fill ()
+			};
+			Top.Add (Win);
+		}
+
+		[System.AttributeUsage (System.AttributeTargets.Class)]
+		public class ScenarioMetadata : System.Attribute {
+			/// <summary>
+			/// Scenario Name
+			/// </summary>
+			public string Name { get; set; }
+
+			/// <summary>
+			/// Scenario Description
+			/// </summary>
+			public string Description { get; set; }
+
+			public ScenarioMetadata (string Name, string Description)
+			{
+				this.Name = Name;
+				this.Description = Description;
+			}
+
+			/// <summary>
+			/// Static helper function to get the Scenario Name given a Type
+			/// </summary>
+			/// <param name="t"></param>
+			/// <returns></returns>
+			public static string GetName (Type t) => ((ScenarioMetadata)System.Attribute.GetCustomAttributes (t) [0]).Name;
+
+			/// <summary>
+			/// Static helper function to get the Scenario Description given a Type
+			/// </summary>
+			/// <param name="t"></param>
+			/// <returns></returns>
+			public static string GetDescription (Type t) => ((ScenarioMetadata)System.Attribute.GetCustomAttributes (t) [0]).Description;
+		}
+
+		/// <summary>
+		/// Helper to get the Scenario Name
+		/// </summary>
+		/// <returns></returns>
+		public string GetName () => ScenarioMetadata.GetName (this.GetType ());
+
+		/// <summary>
+		/// Helper to get the Scenario Descripiton
+		/// </summary>
+		/// <returns></returns>
+		public string GetDescription () => ScenarioMetadata.GetDescription (this.GetType ());
+
+		[System.AttributeUsage (System.AttributeTargets.Class, AllowMultiple = true)]
+		public class ScenarioCategory : System.Attribute {
+			/// <summary>
+			/// Category Name
+			/// </summary>
+			public string Name { get; set; }
+
+			public ScenarioCategory (string Name) => this.Name = Name;
+
+			/// <summary>
+			/// Static helper function to get the Scenario Name given a Type
+			/// </summary>
+			/// <param name="t"></param>
+			/// <returns></returns>
+			public static string GetName (Type t) => ((ScenarioCategory)System.Attribute.GetCustomAttributes (t) [0]).Name;
+
+			/// <summary>
+			/// Static helper function to get the Scenario Categories given a Type
+			/// </summary>
+			/// <param name="t"></param>
+			/// <returns></returns>
+			public static List<string> GetCategories (Type t) => System.Attribute.GetCustomAttributes (t)
+				.ToList ()
+				.Where (a => a is ScenarioCategory)
+				.Select (a => ((ScenarioCategory)a).Name)
+				.ToList ();
+		}
+
+		/// <summary>
+		/// Helper function to get the Categories of a Scenario
+		/// </summary>
+		/// <returns></returns>
+		public List<string> GetCategories () => ScenarioCategory.GetCategories (this.GetType ());
+
+		public override string ToString () => $"{GetName (),-30}{GetDescription ()}";
+
+		/// <summary>
+		/// Override this to implement the Scenario setup logic (create controls, etc...). 
+		/// </summary>
+		public virtual void Setup ()
+		{
+		}
+
+		/// <summary>
+		/// Runs the scenario. Override to start the scearnio using a Top level different than `Top`.
+		/// </summary>
+		public virtual void Run ()
+		{
+			Application.Run (Top);
+		}
+
+		/// <summary>
+		/// Stops the scenario. Override to implement shutdown behavior for the Scenario.
+		/// </summary>
+		public virtual void RequestStop ()
+		{
+			Application.RequestStop ();
+		}
+
+		/// <summary>
+		/// Returns a list of all Categories set by all of the scenarios defined in the project.
+		/// </summary>
+		internal static List<string> GetAllCategories ()
+		{
+			List<string> categories = new List<string> () { "All" };
+			foreach (Type type in typeof (Scenario).Assembly.GetTypes ()
+			    .Where (myType => myType.IsClass && !myType.IsAbstract && myType.IsSubclassOf (typeof (Scenario)))) {
+				List<System.Attribute> attrs = System.Attribute.GetCustomAttributes (type).ToList ();
+				categories = categories.Union (attrs.Where (a => a is ScenarioCategory).Select (a => ((ScenarioCategory)a).Name)).ToList ();
+			}
+			return categories;
+		}
+
+		/// <summary>
+		/// Returns an instance of each Scenario defined in the project. 
+		/// https://stackoverflow.com/questions/5411694/get-all-inherited-classes-of-an-abstract-class
+		/// </summary>
+		internal static List<Type> GetDerivedClassesCollection ()
+		{
+			List<Type> objects = new List<Type> ();
+			foreach (Type type in typeof (Scenario).Assembly.GetTypes ()
+			    .Where (myType => myType.IsClass && !myType.IsAbstract && myType.IsSubclassOf (typeof (Scenario)))) {
+				objects.Add (type);
+			}
+			return objects;
+		}
+	}
+}