org.qt-project.qtdoc.693
qtdoc

# Qt 6.9.3 Reference Documentation

## Reference

### C++ classes

Annotated Class List

Groups Of Related Classes

Obsolete Classes

Inheritance Hierarchy

All Classes by Module

All Namespaces

### QML types

All QML Value Types

Obsolete QML Types

All QML Modules

All Functions and Macros

All Qt Modules

## Getting Started

Introduction

### Get, install, and build Qt

Get and Install Qt with Command Line Interface

Get and Install Qt with Qt Online Installer

#### Building Qt Sources

Getting Qt Sources from the Git repository

Qt Configure Options

Building Optimized Qt

Install Qt Design Studio

Solutions for Application Development

Solutions for UI Design

Mobile Development

Tools for Qt Quick UIs

Tools for Qt Widget-Based UIs

Create Your First Applications

Examples And Tutorials

Explore Qt

What's new in Qt 6

## Product information

### Supported Platforms

#### Qt for Windows

Building from source

Graphics acceleration

Deployment

Specific issues

#### Qt for Linux/X11

Requirements

Building from source

Deployment

Specific issues

Enterprise Qt Debian Packages

Wayland and Qt

Qt Packaging Recommendations

#### Qt for macOS

Building from source

Deployment

Specific issues

#### Qt for Android

Getting started

How Qt for Android Works

Supported versions selection guidelines

Building from source

Building projects from command line

Environment variables

CMake configuration

Supporting Google Emoji Font Policy

Adding OpenSSL support

Android Platform Notes

Android Services

Porting to Android

Deploying an Application on Android

Publishing to Google Play

Using third-party libraries

#### Qt for iOS

Building from Source

Porting to iOS

Platform Notes

#### Qt for Embedded Linux

Configure an Embedded Linux Device

Inputs on an Embedded Linux Device

Fonts

Generate keymaps

#### Qt for INTEGRITY

##### Monolith Project Tutorial

Installing Platform Dependencies

###### Build Qt with Ubuntu host

Building Qt for Qualcomm Snapdragon 8155P Board on Ubuntu

Building a monolith project

Flashing and Running an Image on the 8155P

###### Build Qt with Windows 10 host

Building Qt for Qualcomm Snapdragon 8155P Board on Windows 10

Building and flashing a Dynamic Download Project

#### Qt for QNX

Qt for QNX Support

Building Qt for QNX

Runtime Target Requirements

Qt for VxWorks

Qt for WebAssembly

Qt for webOS

Cross-compiling Qt

Qt Releases

### Qt Licensing

Third-Party Code Used in Qt

License of Qt examples

Android GNU C++ Run-time Licensing

GNU Free Documentation License (FDL)

GNU General Public License (GPL)

GNU Lesser General Public License (LGPL)

The QtEntryPoint Library

Macros for Building with CMake

Mesa llvmpipe

LLVM Attribution

License Changes

Software Bill of Materials

Trademarks

### Qt for Education

Qt Edu resources

Qt Edu for developers

Qt Edu for designers

Developing on Raspberry Pi

Developing with Qt for MCUs

How to Report a Bug

## Overviews

All Overviews

### Development Tools

Resource Compiler (rcc)

User Interface Compiler (uic)

UI Frameworks

Desktop Integration

Networking and Connectivity

Inter-process communication

Qt's Undo Framework

Unicode Support in Qt

### Multi-threading in Qt

Multithreading Technologies

Synchronizing Threads

Reentrancy and Thread-Safety

Threads and QObjects

Thread Support

Examples

### Data Input Output

XML Processing

XML Examples

SQL Examples

### Graphics and Printing

High DPI

### Internationalization

Writing Source Code for Translation

Translation Rules for Plural Forms

Localizing Applications

### Accessibility

Accessibility for QWidget Applications

Accessibility for Qt Quick Applications

Security

Testing and Debugging

Debugging Techniques

### Deploying Qt Applications

Deploying Plugins

Using qt.conf

### Best Practice Guides

How to Create Qt Plugins

Creating Shared Libraries

Exception Safety

Session Management

Calling Qt Functions From Unix Signal Handlers

Setting the Application Icon

Restoring a Window's Geometry

Handling Untrusted Data

### Porting Qt 5 to Qt 6

Changes to Qt Modules in Qt 6

Changes to Qt Extras Modules

Porting C++ Applications to Qt 6 using Clazy checks

Qt Languages

Known Issues

Using the Meta-Object Compiler (moc)

Why Does Qt Use Moc for Signals and Slots?

Differences between String-Based and Functor-Based Connections

accessibility.html
accessible-qtquick.html
accessible-qwidget.html
accessible.html
activeqt-idc.html
activeqt-testcon.html
android-3rdparty-libs.html
android-build-environment-variables.html
android-building-projects-from-commandline.html
android-building.html
android-emojis.html
android-environment-variables.html
android-getting-started.html
android-how-it-works.html
android-openssl-support.html
android-platform-notes.html
android-publishing-to-googleplay.html
android-runtime-licensing-notes.html
android-services.html
android-supported-versions-selection-guidelines.html
android.html
annotated.html
appicon.html
best-practices.html
bughowto.html
build-optimized-qt.html
build-sources.html
building-qt-for-qnx.html
classes.html
classesandfunctions.html
configure-linux-device.html
configure-options.html
create-your-first-applications.html
cross-compiling-qt.html
debug.html
deployment-android.html
deployment-plugins.html
deployment.html
desktop-integration.html
embedded-linux.html
examples-animation.html
examples-draganddrop.html
examples-gestures.html
examples-ios.html
examples-ipc.html
examples-layouts.html
examples-license.html
examples-sql.html
examples-threadandconcurrent.html
examples-widgets-tools.html
examples-xml.html
exceptionsafety.html
explore-qt.html
exportcontrols.html
extras-changes-qt6.html
fdl.html
feature-delivery-example.html
functions.html
get-and-install-qt-cli.html
get-and-install-qt.html
getting-sources-from-git.html
gettingstarted.html
gpl.html
groups.html
hierarchy.html
highdpi.html
i18n-plural-rules.html
i18n-source-translation.html
images/5OiIqFTjUZI.jpg
images/BenchmarkDemoQt6.png
images/CustomStyle_Dark.png
images/CustomStyle_Light.png
images/FX_Material_Showroom.png
images/Material_Dark.png
images/Material_Light.png
images/Settings_CustomStyle.png
images/Settings_Material.png
images/Settings_iOS.png
images/accessibleobjecttree.png
images/addalarms.png
images/alarms2.png
images/alarms3.png
images/android-single-abis.png
images/android-source-folder.png
images/android.webp
images/animation-examples.png
images/arrow_bc.png
images/bgrContent.png
images/btn_next.png
images/btn_prev.png
images/bullet_dn.png
images/bullet_sq.png
images/car_configurator_overview.png
images/coffee_machine_emptycup.png
images/coffee_machine_modify.png
images/coffee_machine_overview.png
images/coffee_machine_selection.png
images/coffee_machine_selection_android_landscape.png
images/coffee_machine_selection_windows.png
images/colorpalette_editing.png
images/colorpalette_listing.png
images/colorpalette_urlselection.png
images/colorpalette_userlisting.png
images/controls.png
images/deployment-mac-application.png
images/deployment-mac-bundlestructure.png
images/desktop_dark.png
images/desktop_light.png
images/detailscreen.png
images/dice-screenshot.webp
images/documentviewer_open.png
images/dprgadget.png
images/dynamic-loaded-pro.png
images/dynamic-pro.png
images/fastboot-mode.png
images/front-coding.png
images/front-ui.png
images/home.png
images/iOS_Dark.png
images/iOS_Light.png
images/ico_out.png
images/integrity-os.png
images/ios.webp
images/layout-examples.png
images/lightningviewer.jpg
images/logo.png
images/macos.webp
images/mainscreen.png
images/maintenancetool.png
images/mediaplayerapp.png
images/mobile_dark.png
images/mobile_light.png
images/nmvurCcsWos.jpg
images/ok.png
images/open-project.png
images/osmbuildings.jpg
images/piemenu.gif
images/project-structure.png
images/project_structure.png
images/qml-application.png
images/qt-android-architecture.drawio.svg
images/qt-codesample.png
images/qt-edu-apply.png
images/qt-edu-browse-qbsp.png
images/qt-edu-contribute.png
images/qt-edu-creator-open.png
images/qt-edu-creator-welcome.png
images/qt-edu-custominstallation.png
images/qt-edu-design-studio-open.png
images/qt-edu-design-studio-welcome.png
images/qt-edu-download.png
images/qt-edu-eeula-terms.png
images/qt-edu-install-design-studio.png
images/qt-edu-install-finish-design-studio.png
images/qt-edu-install-finish-qt.png
images/qt-edu-install-qt.png
images/qt-edu-install-xcode.png
images/qt-edu-login.png
images/qt-edu-maintenancetool.png
images/qt-edu-password.png
images/qt-edu-qbsp-download.png
images/qt-edu-qbsp.png
images/qt-embedded-fontfeatures.png
images/qtcreator-clazy-checks-for-porting-to-qt6.png
images/qtcreator-create-templates.png
images/qtcreator-qt-quick-editors.png
images/qtdesigner.png
images/qtdesignstudio-examples.png
images/qtdesignstudio.png
images/qthangman-example.png
images/qthangman-store-example.png
images/qtinstallercomponents.png
images/qtjenny-sequence.drawio.svg
images/qtjennydemo_overview.png
images/qtquick-demo-calqlatr.png
images/qtquick-demo-clocks-small.png
images/qtquick-demo-photosurface-small.png
images/qtquick-demo-rssnews-small.png
images/qtquick-demo-samegame-med-1.png
images/qtquick-demo-samegame-med-2.png
images/qtquick-demo-stocqt.png
images/qtquick3D.png
images/rhiarch.png
images/robotarm-example.png
images/sa8155-target.png
images/sa8155p.png
images/scalability-gridlayout.png
images/session.png
images/small_dark.png
images/small_light.png
images/sql-examples.png
images/thread-examples.png
images/threadsandobjects.png
images/tool-examples.png
images/txtviewer_screenshot.png
images/vxwb-advanced-settings.png
images/vxwb-cmake-rtp-project.png
images/vxwb-connection.png
images/vxwb-rundebug-settings.png
images/vxwb-rundebug.png
images/wayland-multi-process.png
images/wayland-single-process-develop.png
images/wayland-single-process-eglfs.png
images/windows.webp
images/wiring1.png
images/wiring2.png
images/x11.webp
images/xNIz78IPBu0.jpg
images/xml-examples.png
images/xr_physicsbase_teleportation.jpg
index.html
inputs-linux-device.html
install-qt-design-studio.html
integrity-building-and-flashing-dd-project.html
integrity-building-monolith.html
integrity-building-qt-8155p-on-ubuntu.html
integrity-building-qt-8155p-on-windows.html
integrity-flash-image-and-run.html
integrity-installing-dependencies.html
integrity-linux-monolith.html
integrity-monolith-project-tutorial.html
integrity-win-monolith.html
integrity.html
internationalization.html
ios-building-from-source.html
ios-platform-notes.html
ios.html
ipc-overview.html
known-issues.html
lgpl.html
license-changes.html
licenses-used-in-qt.html
licensing.html
linux-building.html
linux-deployment.html
linux-issues.html
linux-requirements.html
linux.html
localization.html
macos-building.html
macos-deployment.html
macos-issues.html
macos.html
mobiledevelopment.html
moc.html
modulechanges.html
modules-cpp.html
modules-qml.html
modules.html
namespaces.html
newclasses60.html
newclasses61.html
newclasses62.html
newclasses63.html
newclasses64.html
newclasses65.html
newclasses66.html
newclasses67.html
newclasses68.html
newclasses69.html
obsoleteclasses.html
obsoleteqmltypes.html
overviews-main.html
overviews.html
packaging-recommendations.html
plugins-howto.html
porting-qt3d-to-qtquick3d.html
porting-to-android.html
porting-to-ios.html
porting-to-qt6-using-clazy.html
portingguide.html
qmltypes.html
qmlvaluetypes.html
qnx-support.html
qnx-target-requirements.html
qnx.html
qt-activex.html
qt-additional-modules.html
qt-attribution-cmake-macros.html
qt-attribution-llvm.html
qt-attribution-llvmpipe.html
qt-conf.html
qt-debian-packages.html
qt-edu-for-designers.html
qt-edu-for-developers.html
qt-edu-mcu.html
qt-edu-raspberry-pi.html
qt-edu-resources.html
qt-embedded-fonts.html
qt-embedded-kmap2qmap.html
qt-for-education.html
qt-framework-product-information.html
qt-gui-concepts.html
qt-intro.html
qt-online-installation.html
qt-releases.html
qt-tools-utilities.html
qt6-buildsystem.html
qtdoc-attribution-colorpaletteclient.html
qtdoc-attribution-dice-roundcarpet.html
qtdoc-attribution-dice-table.html
qtdoc-attribution-thermostatexample-materialicons.html
qtdoc-attribution-thermostatexample-phosphoricons.html
qtdoc-attribution-todolistexample-materialicons.html
qtdoc-demos-calqlatr-example.html
qtdoc-demos-car-configurator-example.html
qtdoc-demos-clocks-example.html
qtdoc-demos-coffee-example.html
qtdoc-demos-colorpaletteclient-example.html
qtdoc-demos-dice-example.html
qtdoc-demos-documentviewer-example.html
qtdoc-demos-documentviewer-plugins-txtviewer-example.html
qtdoc-demos-fx-material-showroom-example.html
qtdoc-demos-hangman-example.html
qtdoc-demos-lightningviewer-example.html
qtdoc-demos-mediaplayer-example.html
qtdoc-demos-osmbuildings-example.html
qtdoc-demos-photosurface-example.html
qtdoc-demos-qtjennydemo-example.html
qtdoc-demos-robotarm-example.html
qtdoc-demos-rssnews-example.html
qtdoc-demos-samegame-example.html
qtdoc-demos-stocqt-example.html
qtdoc-demos-thermostat-example.html
qtdoc-demos-todolist-example.html
qtdoc-demos-windowembedding-example.html
qtdoc-demos-xr-physicsbase-teleportation-example.html
qtdoc-toc.html
qtdoc-tutorials-alarms-example.html
qtentrypoint.html
qtexamples.html
qtexamplesandtutorials.html
qtjenny-concepts.html
qtjenny-configuration.html
qtjenny-installation.html
qtjenny-knownissues.html
qtjenny-whatsnew.html
qtjenny.html
qtlanguages.html
qtmodules.html
qtpurchasing-androidclasses.html
qtpurchasing-appstore.html
qtpurchasing-baseclasses.html
qtpurchasing-googleplay.html
qtpurchasing-iosclasses.html
qundo.html
rcc.html
reference-overview.html
restoring-geometry.html
sbom.html
scalability.html
security.html
session.html
sharedlibrary.html
signalsandslots-syntaxes.html
solutions-for-application-development.html
solutions-for-ui-design.html
style/offline-dark.css
style/offline-simple.css
style/offline.css
style/tech_preview.svg
supported-platforms.html
testing-and-debugging.html
thread.html
threads-modules.html
threads-qobject.html
threads-reentrancy.html
threads-synchronizing.html
threads-technologies.html
threads.html
tools-for-qt-quick-uis.html
tools-for-qt-widget-based-uis.html
topics-app-development.html
topics-core.html
topics-data-io.html
topics-graphics.html
topics-network-connectivity.html
topics-ui.html
touchinputexamples.html
trademarks.html
uic.html
unicode.html
unix-signals.html
untrusteddata.html
vxworks.html
wasm.html
wayland-and-qt.html
wayland-requirements.html
webos.html
whatsnew60.html
whatsnew61.html
whatsnew62.html
whatsnew63.html
whatsnew64.html
whatsnew65.html
whatsnew66.html
whatsnew67.html
whatsnew68.html
whatsnew69.html
whatsnewqt6.html
why-moc.html
windows-building.html
windows-deployment.html
windows-graphics.html
windows-issues.html
windows.html
xml-processing.html