Terminal.Gui - Cross Platform Terminal GUI toolkit for .NET

A toolkit for building console GUI apps for .NET, .NET Core, and Mono that works on Windows, the Mac, and Linux/Unix.

Controls & Features

Terminal.Gui contains various controls for building text user interfaces:

• Button
• CheckBox
• ComboBox
• Dialog
  • OpenDialog
  • SaveDialog
• FrameView
• GraphView
• Hex viewer/editor
• Label
• ListView
• Menu
• MessageBox
• ProgressBar
• Radio buttons
• TableView
• Time & Date Fields
• TextField
• TextValidateField
• TextView (Text Editor)
• TreeView
• ScrollView
• ScrollBarView
• StatusBar
• Window

In addition, a complete Xterm/Vt100 terminal emulator that you can embed is now part of XtermSharp - you just need to pull TerminalView.cs into your project.

Features

• Cross Platform - Works on Windows, Mac, and Linux. Terminal drivers for Curses, Windows Console, and the .NET Console mean Terminal.Gui works well on both color and monochrome terminals and has mouse support on terminal emulators that support it.
• Keyboard and Mouse Input - Both keyboard and mouse input are supported, including limited support for drag & drop.
• Flexible Layout - Terminal.Gui supports both Absolute layout and an innovative UI layout system referred to as Computed Layout. Computed Layout makes it easy to layout controls relative to each other and enables dynamic console GUIs.
• Clipboard support - Cut, Copy, and Paste of text provided through the Clipboard class.
• Arbitrary Views - All visible UI elements are subclasses of the View class, and these in turn can contain an arbitrary number of sub-views.
• Advanced App Features - The Mainloop supports processing events, idle handlers, timers, and monitoring file descriptors.
• Reactive Extensions Support - Use reactive extensions and benefit from increased code readability, and the ability to apply the MVVM pattern and ReactiveUI data bindings. See the source code of a sample app in order to learn how to achieve this.

Keyboard Input Handling

The input handling of Terminal.Gui is similar in some ways to Emacs and the Midnight Commander, so you can expect some of the special key combinations to be active.

The key ESC can act as an Alt modifier (or Meta in Emacs parlance), to allow input on terminals that do not have an alt key. So to produce the sequence Alt-F, you can press either Alt-F, or ESC followed by the key F.

To enter the key ESC, you can either press ESC and wait 100 milliseconds, or you can press ESC twice.

ESC-0, and ESC-1 through ESC-9 have a special meaning, they map to F10, and F1 to F9 respectively.

Terminal.Gui respects common Mac and Windows keyboard idoms as well. For example, clipboard operations use the familiar Control/Command-C, X, V model.

CTRL-Q is used for exiting views (and apps).

Driver model

Terminal.Gui has support for ncurses, System.Console, and a full Win32 Console front-end.

ncurses is used on Mac/Linux/Unix with color support based on what your library is compiled with; the Windows driver supports full color and mouse, and an easy-to-debug System.Console can be used on Windows and Unix, but lacks mouse support.

You can force the use of System.Console on Unix as well; see Core.cs.

Showcase & Examples

• UI Catalog - The UI Catalog project provides an easy to use and extend sample illustrating the capabilities of Terminal.Gui. Run dotnet run --project UICatalog to run the UI Catalog.
• Reactive Example - A sample app that shows how to use System.Reactive and ReactiveUI with Terminal.Gui. The app uses the MVVM architecture that may seem familiar to folks coming from WPF, Xamarin Forms, UWP, Avalonia, or Windows Forms. In this app, we implement the data bindings using ReactiveUI WhenAnyValue syntax and Pharmacist — a tool that converts all events in a NuGet package into observable wrappers.
• Example (aka demo.cs) - Run dotnet run in the Example directory to run the simple demo.
• Standalone Example - A trivial .NET core sample application can be found in the StandaloneExample directory. Run dotnet run in directory to test.
• F# Example - An example showing how to build a Terminal.Gui app using F#.
• Powershell Sample - (Coming soon! See PR #952. Shows how to build Terminal.Gui apps using Powershell.
• PowerShell's Out-ConsoleGridView - The Out-ConsoleGridView PowerShell Cmdlet sends the output from a command to a grid view window where the output is displayed in an interactive table. sends the output from a command to a grid view window where the output is displayed in an interactive table, using Terminal.Gui.

Documentation

• Overview
• Conceptual Documentation
• API Documentation

See the Terminal.Gui/ README for an overview of how the library is structured. The Conceptual Documentation provides insight into core concepts.

Sample Usage

The code below is done with the new Top-level statements in C# 9.0.

using Terminal.Gui;
using NStack;

Application.Init();
var top = Application.Top;

// Creates the top-level window to show
var win = new Window("MyApp")
{
	X = 0,
	Y = 1, // Leave one row for the toplevel menu

	// By using Dim.Fill(), it will automatically resize without manual intervention
	Width = Dim.Fill(),
	Height = Dim.Fill()
};

top.Add(win);

// Creates a menubar, the item "New" has a help menu.
var menu = new MenuBar(new MenuBarItem[] {
			new MenuBarItem ("_File", new MenuItem [] {
				new MenuItem ("_New", "Creates new file", null),
				new MenuItem ("_Close", "",null),
				new MenuItem ("_Quit", "", () => { if (Quit ()) top.Running = false; })
			}),
			new MenuBarItem ("_Edit", new MenuItem [] {
				new MenuItem ("_Copy", "", null),
				new MenuItem ("C_ut", "", null),
				new MenuItem ("_Paste", "", null)
			})
		});
top.Add(menu);

static bool Quit()
{
	var n = MessageBox.Query(50, 7, "Quit Demo", "Are you sure you want to quit this demo?", "Yes", "No");
	return n == 0;
}

var login = new Label("Login: ") { X = 3, Y = 2 };
var password = new Label("Password: ")
{
	X = Pos.Left(login),
	Y = Pos.Top(login) + 1
};
var loginText = new TextField("")
{
	X = Pos.Right(password),
	Y = Pos.Top(login),
	Width = 40
};
var passText = new TextField("")
{
	Secret = true,
	X = Pos.Left(loginText),
	Y = Pos.Top(password),
	Width = Dim.Width(loginText)
};

// Add some controls, 
win.Add(
	// The ones with my favorite layout system, Computed
	login, password, loginText, passText,

	// The ones laid out like an australopithecus, with Absolute positions:
	new CheckBox(3, 6, "Remember me"),
	new RadioGroup(3, 8, new ustring[] { "_Personal", "_Company" }, 0),
	new Button(3, 14, "Ok"),
	new Button(10, 14, "Cancel"),
	new Label(3, 18, "Press F9 or ESC plus 9 to activate the menubar")
);

Application.Run();

Alternatively, you can encapsulate the app behavior in a new Window-derived class, say App.cs containing the code above, and simplify your Main method to:

using Terminal.Gui;

class Demo {
	static void Main ()
	{
		Application.Run<App> ();
	}
}

The example above shows how to add views using both styles of layout supported by Terminal.Gui: Absolute layout and Computed layout.

Installing

Use NuGet to install the Terminal.Gui NuGet package: https://www.nuget.org/packages/Terminal.Gui

Installation in .NET Core Projects

To install Terminal.Gui into a .NET Core project, use the dotnet CLI tool with following command.

dotnet add package Terminal.Gui

Running and Building

• Windows, Mac, and Linux - Build and run using the .NET SDK command line tools (dotnet build in the root directory). Run UICatalog with dotnet run --project ./UICatalog or by directly executing ./UICatalog/bin/Debug/net5.0/UICatalog.exe.
• Windows - Open Terminal.Gui.sln with Visual Studio 2019.

Building in Release requires the git command line tool (a dependency of the MinVer build tool)

Contributing

See CONTRIBUTING.md.

Debates on architecture and design can be found in Issues tagged with design.

History

This is an updated version of gui.cs that Miguel wrote for mono-curses in 2007.

The original gui.cs was a UI toolkit in a single file and tied to curses. This version tries to be console-agnostic and instead of having a container/widget model, only uses Views (which can contain subviews) and changes the rendering model to rely on damage regions instead of burdening each view with the details.

A presentation of this was part of the Retro.NET talk at .NET Conf 2018 Slides

Release history can be found in the Terminal.Gui.csproj file.

In 2019, 2020, and 2021, Charlie Kindel (https://github.com/tig), @BDisp (https://github.com/BDisp), and Thomas Nind (https://github.com/tznind) vastly extended, improved, polished and fixed gui.cs to what it is today.