path: root/doc/src/platforms/mac-differences.qdoc

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/*!
    \page mac-differences.html
    \title Qt for Mac OS X - Specific Issues
    \brief A description of issues with Qt that are specific to Mac OS X.
    \ingroup platform-specific

    This file outlines known issues and possible workarounds when
    using Qt on Mac OS X. Contact Qt's technical support team if you find
    additional issues which are not covered here. (See also the
    document \l{qtmac-as-native.html} {Qt is Mac OS X Native}.)

    \tableofcontents

    \section1 GUI Applications

    Mac OS X handles most applications as "bundles". A bundle is a
    directory structure that groups related files together (e.g.,
    widgets.app/). GUI applications in particular must be run from a
    bundle or by using the open(1), because Mac OS X needs the bundle
    to dispatch events correctly, as well as for accessing the menu
    bar.

    If you are using older versions of GDB you must run with the full
    path to the executable.  Later versions allow you to pass the
    bundle name on the command line.

    \section1 Painting

    Mac OS X always double buffers the screen so the
    Qt::WA_PaintOnScreen attribute has no effect. Also it is
    impossible to paint outside of a paint event so
    Qt::WA_PaintOutsidePaintEvent has no effect either.

    \section1 Library Support

    \section2 Qt libraries as frameworks

    By default, Qt is built as a set of frameworks. Frameworks is the
    Mac OS X "preferred" way of distributing libraries. There are
    definite advantages to using them. See
    \l{http://developer.apple.com/documentation/MacOSX/Conceptual/BPFrameworks/index.html}
    {Apple's Framework Programming Guide} for more information.

    In general, this shouldn't be an issue because qmake takes care of
    the specifics for you. The
    \l{http://developer.apple.com/documentation/MacOSX/Conceptual/BPFrameworks/index.html}
    {Framework Programming Guide} discusses issues to keep in mind
    when choosing frameworks over the more typical, dynamic libraries.
    However, one point to remember is: \bold {Frameworks always link
    with "release" versions of libraries}.

    If you actually want to use a \e{debug} version of a Qt framework,
    you must ensure that your application actually loads that debug
    version. This is often done by using the DYLD_IMAGE_SUFFIX
    environment variables, but that way often doesn't work so well.
    Instead, you can temporarily swap your debug and release versions,
    which is documented in
    \l{http://developer.apple.com/technotes/tn2004/tn2124.html#SECJUSTONELIB}
    {Apple's "Debugging Magic" technical note}.

    If you don't want to use frameworks, simply configure Qt with
    \c{-no-framework}.

    \section2 Bundle-Based Libraries

    If you want to use some dynamic libraries in your Mac OS X
    application bundle (the application directory), create a
    subdirectory named "Frameworks" in the application bundle
    directory and place your dynamic libraries there. The application
    will find a dynamic library if it has the install name
    \e{@executable_path/../Frameworks/libname.dylib}.

    If you use \c qmake and Makefiles, use the \c QMAKE_LFLAGS_SONAME setting:

    \snippet doc/src/snippets/code/doc_src_mac-differences.qdoc 0

    Alternatively, you can modify the install name using the
    install_name_tool(1) on the command line. See its manpage for more
    information.

    Note that the \c DYLD_LIBRARY_PATH environment variable will
    override these settings, and any other default paths, such as a
    lookup of dynamic libraries inside \c /usr/lib and similar default
    locations.

    \section2 Combining Libraries

    If you want to build a new dynamic library combining the Qt 4
    dynamic libraries, you need to introduce the \c{ld -r} flag. Then
    relocation information is stored in the output file, so that
    this file could be the subject of another \c ld run. This is done
    by setting the \c -r flag in the \c .pro file, and the \c LFLAGS
    settings.

    \section2 Initialization Order

    dyld(1) calls global static initializers in the order they are
    linked into your application. If a library links against Qt and
    references globals in Qt (from global initializers in your own
    library), be sure to link your application against Qt before
    linking it against the library.  Otherwise the result will be
    undefined because Qt's global initializers have not been called
    yet.

    \section1 Compile-Time Flags

    The follewing flags are helpful when you want to define Mac OS X specific
    code:

    \list

    \o Q_OS_DARWIN is defined when Qt detects you are on a
    Darwin-based system (including the Open Source version)

    \o Q_WS_MAC is defined when the Mac OS X GUI is present.

    \o QT_MAC_USE_COCOA is defined when Qt is built to use the Cocoa framework.
    If it is not present, then Qt is using Carbon.

    \endlist

    A additional flag, Q_OS_MAC, is defined as a convenience whenever
    Q_OS_DARWIN is defined.

    If you want to define code for specific versions of Mac OS X, use
    the availability macros defined in /usr/include/AvailabilityMacros.h.

    See QSysInfo for information on runtime version checking.

    \section1 Mac OS X Native API Access

    \section2 Accessing the Bundle Path

    The Mac OS X application is actually a directory (ending with \c
    .app).  This directory contains sub-directories and files. It may
    be useful to place items (e.g. plugins, online-documentation,
    etc.) inside this bundle. You might then want to find out where
    the bundle resides on the disk. The following code returns the
    path of the application bundle:

    \snippet doc/src/snippets/code/doc_src_mac-differences.qdoc 1

    Note: When OS X is set to use Japanese, a bug causes this sequence
    to fail and return an empty string. Therefore, always test the
    returned string.

    For more information about using the CFBundle API, see
    \l{http://developer.apple.com/documentation/CoreFoundation/Reference/CFBundleRef/index.html}
    {Apple's Developer Website}.

    \section2 Translating the Application Menu and Native Dialogs

    The items in the Application Menu will be merged correctly for
    your localized application, but they will not show up translated
    until you 
    \l{http://developer.apple.com/documentation/CoreFoundation/Conceptual/CFBundles/Concepts/BundleAnatomy.html#//apple_ref/doc/uid/20001119-105003-BAJFDAAG}
    {add a localized resource folder} to the application bundle.
    The main thing you need to do is create a file called
    locversion.plist.  Here is an example for Norwegian:

    \snippet doc/src/snippets/code/doc_src_mac-differences.qdoc 2

    Now when you run the application with your preferred language set
    to Norwegian, you should see menu items like "Avslutt" instead of
    "Quit".

    \section1 User Interface

    \section2 Right-Mouse Clicks

    If you want to provide right-mouse click support for Mac OS X, use
    the QContextMenuEvent class. This will map to a context menu
    event, i.e., a menu that will display a pop-up selection. This is
    the most common use of right-mouse clicks, and maps to a
    control-click with the Mac OS X one-button mouse support.

    \section2 Menu Bar

    Qt will automatically detect your menu bars for you and turn
    them into Mac native menu bars. Fitting this into your existing Qt
    application will normally be automatic. However, if you have
    special needs, the Qt implementation currently selects a menu
    bar by starting at the active window
    (i.e. QApplication::activeWindow()) and applying the following
    tests:

    \list 1

    \i If the window has a QMenuBar, then it is used.

    \i If the window is modal, then its menu bar is used. If no menu
       bar is specified, then a default menu bar is used (as
       documented below).

    \i If the window has no parent, then the default menu bar is used
       (as documented below).

    \endlist

    These tests are followed all the way up the parent window chain
    until one of the above rules is satisifed. If all else fails, a
    default menu bar will be created. Note the default menu bar on
    Qt is an empty menu bar. However, you can create a different
    default menu bar by creating a parentless QMenuBar. The first one
    created will be designated the default menu bar and will be used
    whenever a default menu bar is needed.

    Note that using native menu bars introduces certain limitations on
    Qt classes.  See the \l{#Limitations}{list of limitations} below
    for more information about these.

    \section2 Special Keys

    To provide the expected behavior for Qt applications on Mac OS X,
    the Qt::Meta, Qt::MetaModifier, and Qt::META enum values
    correspond to the Control keys on the standard Macintosh keyboard,
    and the Qt::Control, Qt::ControlModifier, and Qt::CTRL enum values
    correspond to the Command keys.

    \section1 Limitations

    \section2 Menu Actions

    \list

    \o Actions in a QMenu with accelerators that have more than one
       keystroke (QKeySequence) will not display correctly, when the
       QMenu is translated into a Mac native menu bar. The first key
       will be displayed. However, the shortcut will still be
       activated as on all other platforms.

    \o QMenu objects used in the native menu bar are not able to
       handle Qt events via the normal event handlers.
       For Carbon, you will have to install a Carbon event handler on
       the menu bar in order to receive Carbon events that are similar
       to \l{QMenu::}{showEvent()}, \l{QMenu::}{hideEvent()}, and
       \l{QMenu::}{mouseMoveEvent()}. For Cocoa, you will have to
       install a delegate on the menu itself to be notified of these
       changes. Alternatively, consider using the QMenu::aboutToShow()
       and QMenu::aboutToHide() signals to keep track of menu visibility;
       these provide a solution that should work on all platforms
       supported by Qt.

    \endlist

    \section2 Native Widgets

    Qt has support for sheets and drawers, represented in the
    window flags by Qt::Sheet and Qt::Drawer respectiviely. Brushed
    metal windows can also be created by using the
    Qt::WA_MacMetalStyle window attribute.

*/

/*!
    \page qt-mac-cocoa-licensing.html

    \title Contributions to the Following QtGui Files: qapplication_cocoa_p.h, qapplication_mac.mm, qdesktopwidget_mac.mm qeventdispatcher_mac.mm qeventdispatcher_mac_p.h qmacincludes_mac.h qt_cocoa_helpers.mm qt_cocoa_helpers_p.h qwidget_mac.mm qsystemtrayicon_mac.mm

    \contentspage {Other Licenses Used in Qt}{Contents}

    \ingroup licensing
    \brief License information for contributions by Apple, Inc. to specific parts of the Qt for Mac OS X Cocoa port.

    \legalese

    Copyright (C) 2007-2008, Apple, Inc.

    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:

    \list
    \o Redistributions of source code must retain the above copyright notice,
       this list of conditions and the following disclaimer.
    \o Redistributions in binary form must reproduce the above copyright notice,
       this list of conditions and the following disclaimer in the documentation
       and/or other materials provided with the distribution.
    \o Neither the name of Apple, Inc. nor the names of its contributors
       may be used to endorse or promote products derived from this software
       without specific prior written permission.
    \endlist

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    \endlegalese
*/