TextCore.Native — UI-agnostic Cross-Platform Core Text APIs

TextCore.Native offers a small, stable set of CoreText/IME primitives editor hosts can use to implement platform text input and IME support without depending on Uno Platform, WPF, or any other UI framework. It exposes a managed CoreText* API surface and uses different approaches for platform integration:

• On Windows, it uses the Win32 IME APIs (user32/imm32) via P/Invoke.
• On macOS, it includes a tiny native macOS helper (libTextCoreNativeMacInput.dylib) used to surface AppKit text input callbacks to managed code.
• On Linux, it uses libX11 via P/Invoke for X11 calls and communicates with IBus over D-Bus using a built-in managed DBus-over-socket implementation (no libibus/libdbus P/Invoke).

Quick start

• Install the NuGet package:

dotnet add package LeXtudio.UI.Text.Core

• Or add a PackageReference to your project file:

<PackageReference Include="LeXtudio.UI.Text.Core" Version="1.*" />

For advanced workflows (consuming from source, building the native macOS helper, or producing packages) see CONTRIBUTING.md.

API overview

• CoreTextServicesManager.GetForCurrentView() — factory; call CreateEditContext() to get a CoreTextEditContext.
• CoreTextEditContext — central event hub. Important events:
  • TextRequested
  • TextUpdating
  • SelectionRequested
  • SelectionUpdating
  • LayoutRequested
  • CompositionStarted / CompositionCompleted / FocusRemoved
  • CommandReceived — receives platform command selectors (e.g. AppKit doCommandBySelector: strings).

Lifecycle methods:

• bool AttachToWindowHandle(nint windowHandle, nint displayHandle = 0) — attach to a native window. On macOS pass an NSWindow*; on Windows pass an HWND; on Linux/X11 pass the X11 Window id and the X11 Display pointer.
• void NotifyCaretRectChanged(double x, double y, double width, double height).
• void NotifyFocusEnter() / void NotifyFocusLeave().
• void Dispose().

Minimal usage example

var manager = CoreTextServicesManager.GetForCurrentView();
var ctx = manager.CreateEditContext();

ctx.TextRequested += (s, e) => e.Request.Text = GetDocumentText();
ctx.TextUpdating += (s, e) => ApplyEdit(e.NewText);
ctx.CommandReceived += (s, e) => {
  if (e.Command == "deleteBackward:") { Backspace(); e.Handled = true; }
};

ctx.AttachToWindowHandle(hwnd);
ctx.NotifyCaretRectChanged(x, y, w, h);
// ...
ctx.Dispose();

License

This project is licensed under the MIT License. See the LICENSE file for details.

Copyright

(c) 2026 LeXtudio Inc. All rights reserved.