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/*!
    \page appicon.html
    \title Setting the Application Icon
    \brief How to set your application's icon.

    \ingroup best-practices

    The application icon, typically displayed in the top-left corner of an
    application's top-level windows, is set by calling the
    QWindow::setWindowIcon() method.

    In order to change the icon of the executable application file
    itself, as it is presented on the desktop (i.e., prior to
    application execution), it is necessary to employ another,
    platform-dependent technique.

    \tableofcontents

    \section1 Setting the Application Icon on Windows

    First, create an ICO format bitmap file that contains the icon
    image. This can be done with e.g. Microsoft Visual C++: Select
    \menu{File|New}, then select the \menu{File} tab in the dialog
    that appears, and choose \menu{Icon}. (Note that you do not need
    to load your application into Visual C++; here we are only using
    the icon editor.)

    Store the ICO file in your application's source code directory,
    for example, with the name \c myappico.ico.

    Then, assuming you are using qmake to generate your makefiles,
    you only need to add a single line to your \c .pro project file:

    \snippet snippets/code/doc_src_appicon.pro 0

    Finally, regenerate your makefile and your application. The \c .exe file
    will now be represented by your icon in Explorer.

    However, if you already have an \c .rc file, for example, with the name
    \c myapp.rc, which you want to reuse, the following two steps will be
    required. First, put a single line of text to the \c myapp.rc file:

    \snippet snippets/code/doc_src_appicon.qdoc 0

    Then, add this line to your \c myapp.pro file:

    \snippet snippets/code/doc_src_appicon.pro 1

    If you do not use \c qmake, the necessary steps are: first, create an
    \c .rc file and run the \c rc or \c windres program on the \c .rc file,
    then link your application with the resulting \c .res file.

    \section1 Setting the Application Icon on OS X

    The application icon, typically displayed in the application dock
    area, is set by calling QWindow::setWindowIcon() on a window. It is
    possible that the program could appear in the application dock area
    before the function call, in which case a default icon will appear
    during the bouncing animation.

    To ensure that the correct icon appears, both when the application is
    being launched, and in the Finder, it is necessary to employ a
    platform-dependent technique.

    Although many programs can create icon files (\c .icns), the
    recommended approach is to use the \e{Icon Composer} program
    supplied by Apple (in the \c Developer/Application folder).
    \e{Icon Composer} allows you to import several different sized
    icons (for use in different contexts) as well as the masks that
    go with them. Save the set of icons to a file in your project
    directory.

    If you are using qmake to generate your makefiles, you only need
    to add a single line to your \c .pro project file. For example,
    if the name of your icon file is \c{myapp.icns}, and your project
    file is \c{myapp.pro}, add this line to \c{myapp.pro}:

    \snippet snippets/code/doc_src_appicon.pro 2

    This will ensure that \c qmake puts your icons in the proper
    place and creates an \c{Info.plist} entry for the icon.

    If you do not use \c qmake, you must do the following manually:
    \list 1
    \li Create an \c Info.plist file for your application (using the
       \c PropertyListEditor, found in \c Developer/Applications).
    \li Associate your \c .icns record with the \c CFBundleIconFile record in the
       \c Info.plist file (again, using the \c PropertyListEditor).
    \li Copy the \c Info.plist file into your application bundle's \c Contents
       directory.
    \li Copy the \c .icns file into your application bundle's \c Contents/Resources
       directory.
    \endlist

    \section1 Setting the Application Icon on Common Linux Desktops

    In this section we briefly describe the issues involved in providing
    icons for applications for two common Linux desktop environments:
    \l{http://www.kde.org/}{KDE} and \l{http://www.gnome.org/}{GNOME}.
    The core technology used to describe application icons
    is the same for both desktops, and may also apply to others, but there
    are details which are specific to each. The main source of information
    on the standards used by these Linux desktops is
    \l{http://www.freedesktop.org/}{freedesktop.org}. For information
    on other Linux desktops please refer to the documentation for the
    desktops you are interested in.

    Often, users do not use executable files directly, but instead launch
    applications by clicking icons on the desktop. These icons are
    representations of "desktop entry files" that contain a description of
    the application that includes information about its icon. Both desktop
    environments are able to retrieve the information in these files, and
    they use it to generate shortcuts to applications on the desktop, in
    the start menu, and on the panel.

    More information about desktop entry files can be found in the
    \l{http://www.freedesktop.org/Standards/desktop-entry-spec}{Desktop Entry
    Specification}.

    Although desktop entry files can usefully encapsulate the application's details,
    we still need to store the icons in the conventional location for each desktop
    environment. A number of locations for icons are given in the
    \l{http://www.freedesktop.org/Standards/icon-theme-spec}{Icon Theme
    Specification}.

    Although the path used to locate icons depends on the desktop in use,
    and on its configuration, the directory structure beneath each of
    these should follow the same pattern: subdirectories are arranged by
    theme, icon size, and application type. Generally, application icons
    are added to the hicolor theme, so a square application icon 32 pixels
    in size would be stored in the \c hicolor/32x32/apps directory beneath
    the icon path.

    \section2 K Desktop Environment (KDE)

    Application icons can be installed for use by all users, or on a per-user basis.
    A user currently logged into their KDE 4 desktop can discover these locations
    by using kde4-config, for example, by typing the following in a terminal window:

    \snippet snippets/code/doc_src_appicon.qdoc 3

    Applications using Qt 5 and KDE Frameworks 5 will find their icons in the list
    returned by this command:

    \snippet snippets/code/doc_src_appicon.qdoc 5

    Typically, the list of colon-separated paths printed to stdout includes the
    user-specific icon path and the system-wide path. Beneath these
    directories, it should be possible to locate and install icons according
    to the conventions described in the
    \l{http://www.freedesktop.org/Standards/icon-theme-spec}{Icon Theme Specification}.

    If you are developing exclusively for KDE, you may wish to take
    advantage of the \link
    http://techbase.kde.org/Development/CMake/Addons_for_KDE
    KDE build system\endlink to configure your application. This ensures
    that your icons are installed in the appropriate locations for KDE.

    The KDE developer website is at \l{http://techbase.kde.org/}.

    \section2 GNOME

    Application icons are stored within a standard system-wide
    directory containing architecture-independent files. This
    location can be determined by using \c gnome-config, for example
    by typing the following in a terminal window:

    \snippet snippets/code/doc_src_appicon.qdoc 4

    The path printed on stdout refers to a location that should contain a directory
    called \c{pixmaps}; the directory structure within the \c pixmaps
    directory is described in the \link
    http://www.freedesktop.org/Standards/icon-theme-spec Icon Theme
    Specification \endlink.

    If you are developing exclusively for GNOME, you may wish to use
    the standard set of \link
    http://developer.gnome.org/tools/build.html GNU Build Tools\endlink,
    also described in the relevant section of
    the \link http://developer.gnome.org/doc/GGAD/ggad.html GTK+/Gnome
    Application Development book\endlink. This ensures that your icons are
    installed in the appropriate locations for GNOME.

    The GNOME developer website is at \l{http://developer.gnome.org/}.
*/
