qt-creator/doc/qtcreator/src/webassembly/creator-webassembly.qdoc

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    /*!
    \previouspage creator-developing-qnx.html
    \page creator-setup-webassembly.html
    \nextpage creator-build-process-customizing.html

    \title Building Applications for the Web

    WebAssembly is a binary format that allows sand-boxed executable code in
    web pages. This format is nearly as fast as native machine code, and is
    now supported by all major web browsers.

    \l {Qt for WebAssembly} enables building Qt applications so that they can be
    integrated into web pages. It doesn't require any client-side installations
    and reduces the use of server-side resources.

    The experimental WebAssembly plugin enables you to build your applications
    in WebAssembly format and deploy and run them in the local web browser.
    You can change the web browser in the project run settings.

    To build applications for the web and run them in a web browser, you need to
    install Qt for WebAssembly and the tool chain for compiling to WebAssembly.

    \section1 Requirements

    You need the following software to build Qt applications for the web and run
    them in a browser:

    \list
        \li Qt for WebAssembly 5.13.1, or later
        \li On Windows: \l{http://wiki.qt.io/MinGW}{\MinGW} 7.3.0, or later
        \li \l{https://emscripten.org/docs/introducing_emscripten/index.html}
            {emscripten} tool chain for compiling to WebAssembly
        \li \c sed stream editor
    \endlist

    \note You need to add the location of the \MinGW and \c sed installation
    folders to the system path, either globally or for the Qt for WebAssembly
    kit.

    \section1 Setting Up the Development Environment

    You need to install and configure Qt for WebAssembly and the tool chain for
    compiling to WebAssembly. The installer automatically adds a build and run
    kit to \QC.

    \section2 Setting Up Qt for WebAssembly

    To set up Qt for WebAssembly:

        \list 1
        \li Use the Qt maintenance tool to install Qt for WebAssembly and, on
            Windows, \MinGW (found in \uicontrol {Developer and Designer Tools}).
        \li Check out \c emsdk and install and activate \c emscripten, as
            instructed in \l {Qt for WebAssembly}.
            \note Do not use the \c{--embedded} option for activating the
            \c emscripten version in the \c emsdk, because \QC
            expects to find the \c{.emscripten} file describing the toolchain in
            your home directory.
        \li On Windows, you have to download and install \c sed, as instructed
            in \l{http://gnuwin32.sourceforge.net/packages/sed.htm}
            {sed for Windows}.
        \endlist

    \section2 Enabling the WebAssembly Plugin

    To enable the plugin:

    \list 1
        \li In \QC, select \uicontrol Help > \uicontrol {About Plugins} >
            \uicontrol {Device Support} > \uicontrol {WebAssembly}.
        \li Select \uicontrol {Restart Now} to restart \QC and load the plugin.
    \endlist

    \section2 Specifying WebAssembly Settings

    To configure \QC for building Qt apps for the web:

    \list 1
        \li Select \uicontrol Tools > \uicontrol Options > \uicontrol Kits.
            \image qtcreator-kit-webassembly.png "Qt for WebAssembly kit"
        \li In the \uicontrol Compiler group, \uicontrol {Emscripten Compiler}
            should have been automatically detected for both C++ and C. If not,
            check that emscripten is set up correctly and your home directory
            contains an \c{.emscripten} file.
        \li Select \uicontrol Change next to the \uicontrol Environment
            field to append the locations where you installed \MinGW and
            \c sed to the PATH variable. For example, on Windows:
            \c {PATH=C:\Qt\Tools\mingw730_64\bin;C:\Program Files (x86)\GnuWin32\bin;${PATH}}
            \li Select \uicontrol Apply to save the changes to the kit.
    \endlist

    \section2 Adding WebAssembly Kits

    The Qt for Web Assembly installation automatically adds build and run kits
    to \QC. To add kits:

    \list 1
        \li Select \uicontrol Tools > \uicontrol Options > \uicontrol Kits >
            \uicontrol Add.
        \li In the \uicontrol Name field, specify a name for the kit.
        \li In the \uicontrol {Device type} field, select
            \uicontrol {WebAssembly Runtime}.
            The value of the \uicontrol Device field is automatically
            set to \uicontrol {Web Browser}.
        \li In the \uicontrol Compiler field, select
            \uicontrol {Emscripten Compiler} for both C and C++.
        \li Select \uicontrol Change next to the \uicontrol Environment
            field to append the locations where you installed \MinGW and
            \c sed to the PATH variable.
        \li Select \uicontrol Apply to add the kit.
    \endlist

    \section1 Running Applications in a Web Browser

    To run a project:

    \list 1
        \li Open a project for an application you want to run in a web browser.
        \li Select \uicontrol Projects > \uicontrol {Build & Run}, and then
            select the WebAssembly kit as the build and run kit for the project.
        \li Select \uicontrol Run to specify run settings.
        \li In the \uicontrol Browser field, select the browser to run the
            application in.
            \image qtcreator-settings-run-webassembly.png "Selecting the browser to run in"
    \endlist

    You can now build Qt applications in WebAssembly format and run them in
    a web browser as described in \l {Building for Multiple Platforms} and
    \l{Running on Multiple Platforms}.
*/