deployment.qdoc

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// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qtquick-deployment.html
\meta {keywords} {qmltopic}
\title Deploying QML Applications
\brief Provides information on how to use deploy QML applications.
 
This page provides information on how to deploy QML applications. It covers the
use of \QC for deployment, and the use of the Qt Resource System to package QML
files and other resources with the application executable.
 
\section1 Deploying applications with \QC
 
\l{\QC Documentation}{\QC} deploys and packages QML applications to various
platforms. For mobile devices, \QC can directly bundle applications to the
respective platform package formats, such as APK.
 
When you run your applications on the target platform, your application needs
to access the location of the QML libraries. If you use
\l{qmake Manual}{qmake}, the \c QT_INSTALL_QML environment variable points to
the location of the libraries. The \l{Downloads}{Qt Installers} install the QML
libraries in: \c{<version>}\c{/}\e{<compiler>}\c{/qml} directory.
 
 
\section1 Using the Qt Resource System with QML
 
The \l {The Qt Resource System}{Qt resource system} allows resource files to be
stored as binary files in an application executable. The Qt Resource System is
used for QML application as it enables QML files and other resources -- such as
images and sound files -- to be referred to through the resource system URI
scheme rather than relative or absolute paths to filesystem resources.
 
\note Usage of the resource system means that the application executable
usually must be re-compiled whenever a QML source file is changed, to update
the resources in the package.
 
The \l{qt_add_qml_module}{CMake QML Module API} automatically places your QML
files in the resource system. To access them, load your main QML file as a
resource or as a URL with the \c{qrc} scheme. The path in the resource system
where your QML files are placed can be found by concatenating:
 
\list
\li the \c RESOURCE_PREFIX you have passed to \l{qt_add_qml_module}.
\li \c{/qt/qml}, if you have \e{not} passed \c RESOURCE_PREFIX to
    \l{qt_add_qml_module} and \l{QTP0001} policy is set to \c NEW.
\li \c{/}, if you have \e{not} passed \c RESOURCE_PREFIX to \l{qt_add_qml_module}
    and \l{QTP0001} policy is \c{not} set to \c NEW.
\li If you have \e{not} passed \c NO_RESOURCE_TARGET_PATH to \l{qt_add_qml_module}:
    the \c URI you have passed to \l{qt_add_qml_module} with dots replaced by slashes.
\endlist
 
For example, a module called \c{My.Own.Module} is placed at:
\list
\li \c{:/qt/qml/My/Own/Module/} if you have specified \c{/qt/qml} as \c RESOURCE_PREFIX, or
    you have \e{not} passed \c RESOURCE_PREFIX and \l{QTP0001} policy is set to \c NEW.
\li \c{:/My/Own/Module/} if you have specified \c{/} as \c RESOURCE_PREFIX, or
    you have \e{not} passed \c RESOURCE_PREFIX and \l{QTP0001} policy is \e{not} set to \c NEW.
\li \c{:/Some/Prefix/My/Own/Module/} if you have specified \c{Some/Prefix/} as \c RESOURCE_PREFIX
\li \c{:/} if you have specified \c NO_RESOURCE_TARGET_PATH
\endlist
 
Once this is done, all files specified by relative paths in QML are loaded from
the resource system. Use of the resource system is completely transparent to
the QML layer; this means all QML code should refer to resource files using
relative paths and should \e{not} use the \c{qrc} scheme. This scheme should
only be used from C++ code to refer to resource files.
 
\note When using qmake, you need to manually place your files in the resource
system. See the \l{qmake Manual} and the \l{The Qt Resource System}{general
documentation} on the resource system for how to do this. It's advisable to
still follow the path naming convention outlined above.
 
\section1 Related Information
\list
    \li \l{Deploying Qt Applications}
    \li \l{\QC: Run on many platforms}
    \li \l{Data Type Conversion Between QML and C++}{Exposing Attributes of C++ Types to QML}
    \li \l{The Qt Resource System}
\endlist
 
*/