Files
Terminal.Gui/Examples/UICatalog
Copilot 6d53276be2 Fixes #4289 - Simplify Drawing/Color: unify named color handling under StandardColor and remove layered resolvers (#4432)
* Initial plan

* Delete AnsiColorNameResolver and MultiStandardColorNameResolver, add legacy 16-color names to StandardColor

Co-authored-by: tig <585482+tig@users.noreply.github.com>

* Refactor and enhance tests for Color, Region, and Lines

Refactored `Color` struct by removing unused methods and simplifying logic. Updated namespaces for better organization. Enhanced test coverage for `Color`, `Region`, and `LineCanvas` with new test cases, parameterized tests, and edge case handling.

Added `StraightLineExtensionsTests`, `StraightLineTests`, and `RegionClassTests` to validate behavior under various scenarios. Improved `MergeRectangles` stability and addressed crash patterns. Removed legacy features and unused code. Enhanced documentation and optimized performance in key methods.

* Improve Color struct and StandardColors functionality

Enhanced the Color struct to fully support the alpha channel for rendering intent while maintaining semantic color identity. Updated TryNameColor to ignore alpha when matching colors, ensuring transparency does not affect color resolution. Expanded XML documentation to clarify alpha channel usage and future alpha blending support.

Improved drawing documentation to explain the lifecycle, deferred rendering, and color support, including 24-bit true color and legacy 16-color compatibility. Added a new section on transparency and its role in rendering.

Revised StandardColors implementation to use modern C# features and ensure consistent ARGB mapping. Added comprehensive tests for StandardColors and Color, covering alpha handling, color parsing, thread safety, and aliased color resolution. Removed outdated tests relying on legacy behavior.

Enhanced code readability, maintainability, and test coverage to ensure correctness and backward compatibility.

* Code cleanup

* Code cleanup

* Fix warnings. Code cleanup

* Add comprehensive unit tests for ColorStrings class

Introduced a new test class `ColorStringsTests` under the
`DrawingTests.ColorTests` namespace to validate the functionality
of the `ColorStrings` class.

Key changes include:
- Added tests for `GetColorName` to verify behavior for standard
  and non-standard colors, ignoring alpha channels, and handling
  known colors.
- Added tests for `GetStandardColorNames` to ensure the method
  returns a non-empty, alphabetically sorted collection containing
  all `StandardColor` enum values.
- Implemented tests for `TryParseStandardColorName` to validate
  case-insensitive parsing, hex color support, handling invalid
  input, and `ReadOnlySpan<char>` compatibility.
- Added tests for `TryParseNamedColor` to verify parsing of named
  and hex colors, handling of aliases, and `ReadOnlySpan<char>`
  support.
- Added round-trip tests to ensure consistency between
  `GetColorName`, `TryParseNamedColor`, `GetStandardColorNames`,
  and `TryParseStandardColorName`.

These tests ensure robust validation of color parsing and naming
functionality.

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: tig <585482+tig@users.noreply.github.com>
Co-authored-by: Tig <tig@users.noreply.github.com>
2025-12-03 11:09:02 -07:00
..

Terminal.Gui UI Catalog

UI Catalog is a comprehensive sample library for Terminal.Gui. It attempts to satisfy the following goals:

  1. Be an easy-to-use showcase for Terminal.Gui concepts and features.
  2. Provide sample code that illustrates how to properly implement said concepts & features.
  3. Make it easy for contributors to add additional samples in a structured way.

screenshot

Motivation

The original demo.cs sample app for Terminal.Gui is neither good to showcase, nor does it explain different concepts. In addition, because it is built on a single source file, it has proven to cause friction when multiple contributors are simultaneously working on different aspects of Terminal.Gui. See Issue #368 for more background.

API Reference

How To Use

Build and run UI Catalog by typing dotnet run from the UI Catalog folder or by using the Terminal.Gui Visual Studio solution.

Program.cs is the main UI Catalog app and provides a UI for selecting and running Scenarios. Each *Scenario is implemented as a class derived from Scenario and Program.cs uses reflection to dynamically build the UI.

Scenarios are tagged with categories using the [ScenarioCategory] attribute. The left pane of the main screen lists the categories. Clicking on a category shows all the scenarios in that category.

Scenarios can be run either from the UICatalog.exe app UI or by being specified on the command line:

UICatalog.exe <Scenario Name>

e.g.

UICatalog.exe Buttons

Hitting ENTER on a selected Scenario or double-clicking on a Scenario runs that scenario as though it were a stand-alone Terminal.Gui app.

When a Scenario is run, it runs as though it were a standalone Terminal.Gui app. However, scaffolding is provided (in the Scenario base class) that (optionally) takes care of Terminal.Gui initialization.

Contributing by Adding Scenarios

To add a new Scenario simply:

  1. Create a new .cs file in the Scenarios directory that derives from Scenario.
  2. Add a [ScenarioMetaData] attribute to the class specifying the scenario's name and description.
  3. Add one or more [ScenarioCategory] attributes to the class specifying which categories the sceanrio belongs to. If you don't specify a category the sceanrio will show up in "All".
  4. Implement the Setup override which will be called when a user selects the scenario to run.
  5. Optionally, implement the Init and/or Run overrides to provide a custom implementation.

The sample below is provided in the .\UICatalog\Scenarios directory as a generic sample that can be copied and re-named:


namespace UICatalog {
	[ScenarioMetadata (Name: "Generic", Description: "Generic sample - A template for creating new Scenarios")]
	[ScenarioCategory ("Controls")]
	class MyScenario : Scenario {
		public override void Setup ()
		{
			// Put your scenario code here, e.g.
			Win.Add (new Button () { 
Text = "Press me!", 
				X = Pos.Center (),
				Y = Pos.Center (),
				Clicked = () => MessageBox.Query (20, 7, "Hi", "Neat?", "Yes", "No")
			});
		}
	}
}

Scenario provides Win, a Window object that provides a canvas for the Scenario to operate.

The default Window shows the Scenario name and supports exiting the Scenario through the Esc key.

screenshot

To build a more advanced scenario, where control of the Runnable and Window is needed (e.g. for scenarios using MenuBar or StatusBar), simply use Application.Top per normal Terminal.Gui programming, as seen in the Notepad scenario.

For complete control, the Init and Run overrides can be implemented. The base.Init creates Win. The base.Run simply calls Application.Run(Application.Top).

Contribution Guidelines

  • Provide a terse, descriptive Name for Scenarios. Keep them short.
  • Provide a clear Description.
  • Comment Scenario code to describe to others why it's a useful Scenario.
  • Annotate Scenarios with [ScenarioCategory] attributes. Minimize the number of new categories created.
  • Use the Bug Repo Category for Scenarios that reproduce bugs.
    • Include the Github Issue # in the Description.
    • Once the bug has been fixed in develop submit another PR to remove the Scenario (or modify it to provide a good regression test/sample).
  • Tag bugs or suggestions for UI Catalog as Terminal.Gui Github Issues with "UICatalog: ".