Qt Bridge C# Extension for VS Code

This extension integrates Qt Bridge C# projects with the Qt Extension for VS Code.

It provides:

• Qt Bridge C# project discovery, including multi-project workspaces
• Qt installation and QML import-root resolution before the first build
• build-generated QML metadata discovery and readiness tracking
• QML Preview launch preparation through a public API
• QML Language Server and live-preview integration through the Qt QML extension

Build the Qt Bridge project once to generate the metadata required for complete QML Language Server and live-preview support.

Prerequisites

The Qt Core extension is required. Install the Qt QML extension for QML Language Server, QML Preview, and QML Profiler support. C# Dev Kit is recommended for normal C# editing and debugging but is not required by the Qt Bridge integration.

To create a project, run Qt: Create a new project or file and select Qt Bridge for C# application. Use the Qt Bridge for C# QML file item to add QML files to an existing project.

Qt installation

Building a Qt Bridge project needs a Qt installation, which is set with QtDir. Only the Windows x64 package bundles Qt. On Windows ARM64, Linux, and macOS, QtDir is required.

If a build would not find Qt, the extension asks you to select one. Run Qt Bridge C#: Select Qt Installation to select it later. The selection is stored in the qt-csharp.qtDir setting and exported as QtDir to the integrated terminal, so builds started there use the same Qt as the QML tooling. For builds started elsewhere, for example by C# Dev Kit, set QtDir in the environment or in the project.

The extension resolves Qt from the project, the qt-csharp.qtDir setting, the QtDir environment variable, or the Qt selected by Qt Core, in that order. The Qt bundled by the Windows x64 package is used only as the final fallback.

Debug QML code

Projects created from the Qt Bridge for C# application template have a .vscode/launch.json with a configuration for the QML debugger of the Qt QML extension. Select Qt Bridge: QML and start debugging.

For other projects, add the configuration to launch.json. It uses ${command:qt-csharp.launchTargetPath} as the program:

{
  "name": "Qt Bridge: QML",
  "type": "qml",
  "request": "launch",
  "program": "${command:qt-csharp.launchTargetPath}"
}

The command resolves the executable of the project that contains the active file, or asks which project to use when there are several. Build the project first; the command does not build it. If you built the project in several configurations or for several target frameworks, select one with Qt Bridge C#: Select QML Build Metadata.

Breakpoints in QML code that runs right when the application starts can be missed.

Documentation

For Qt Bridge C# setup and project documentation, see the Qt Bridge C# documentation.

For information about the Qt extensions, see the Qt Extension for VS Code documentation.

For pre-release documentation, see the Qt Extension for VS Code pre-release documentation.

Issues

Report issues in the Qt VS Code extension project.

License

This extension is available under the Qt Commercial License or LGPL 3.0. See LICENSE for the license text.