- Qt 6.9
- Build with CMake
- Deployment
- Qt 6.9.3 Reference Documentation

Building projects on the command line ◦ Supported CMake versions

# Deployment

Use Qt's CMake deployment API to deploy Qt projects for desktop platforms. The API supports various target platforms, which you can find in the qt_generate_deploy_app_script() documentation.

The deployment process depends on whether your project is a Qt Widgets application or a Qt Quick application. Even if you are planning to deploy only Qt Quick applications, read about deploying Qt Widgets applications first to understand the process.

## Deploying a Qt Widgets application

This section shows how to deploy a Qt Widgets application with an example of a simple C++ Qt project.

     cmake_minimum_required(VERSION 3.16)

     project(MyApp VERSION 1.0.0 LANGUAGES CXX)

     set(CMAKE_CXX_STANDARD 17)
     set(CMAKE_CXX_STANDARD_REQUIRED ON)

     find_package(Qt6 REQUIRED COMPONENTS Core)
     qt_standard_project_setup()

     qt_add_executable(MyApp main.cpp)
     target_link_libraries(MyApp PRIVATE Qt6::Core)

You need to instruct CMake to install the application target into the appropriate location. On macOS, bundles are installed directly into `${CMAKE_INSTALL_PREFIX}`, on other platforms into the `"bin"` directory underneath.

     install(TARGETS MyApp
         BUNDLE  DESTINATION .
         RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     )

Note that qt_standard_project_setup() pulls in CMake's `GNUInstallDirs.cmake`. This is what defines the `CMAKE_INSTALL_BINDIR` variable.

You also need to generate a deployment script. A deployment script is CMake code that is executed at installation time. This code takes care of collecting runtime dependencies and copies them to the installation directory.

     qt_generate_deploy_app_script(
         TARGET MyApp
         OUTPUT_SCRIPT deploy_script
         NO_UNSUPPORTED_PLATFORM_ERROR
     )
     install(SCRIPT ${deploy_script})

The qt_generate_deploy_app_script() command generates the deployment script in the build directory. The file name of the generated script file is stored in the `deploy_script` variable. The `install(SCRIPT)` call instructs CMake to run the script on installation.

The project can be installed with `cmake --install .` or `ninja install` like any other CMake-based project. After installation, the installation directory contains the shared libraries and assets that are necessary to run the application. In other words, the installation produces a self-contained directory, ready to be packaged - for example by `cpack`.

## Deploying a Qt Quick application

Deploying a Qt Quick project requires a different command to generate the deployment script. The rest of the steps are similar to deploying a Qt Widgets application.

First, you create the Qt Quick application.

     cmake_minimum_required(VERSION 3.16)

     project(MyApp VERSION 1.0.0 LANGUAGES CXX)

     set(CMAKE_CXX_STANDARD 17)
     set(CMAKE_CXX_STANDARD_REQUIRED ON)

     find_package(Qt6 REQUIRED COMPONENTS Core)
     qt_standard_project_setup()

     qt_add_executable(MyApp main.cpp)
     qt_add_qml_module(MyApp
         URI Application
         VERSION 1.0
         QML_FILES main.qml MyThing.qml
     )

You install the application as before.

     install(TARGETS MyApp
         BUNDLE  DESTINATION .
         RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     )

To generate the deployment script, you call qt_generate_deploy_qml_app_script() instead of qt_generate_deploy_app_script().

     qt_generate_deploy_qml_app_script(
         TARGET MyApp
         OUTPUT_SCRIPT deploy_script
     )
     install(SCRIPT ${deploy_script})

On installation, the application binary will be deployed, including the QML files and the shared libraries and assets of Qt that are used by the project. Again, the resulting directory is self-contained and can be packaged by tools like `cpack`.