src/gui/util/qdesktopservices.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/util/qdesktopservices.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,320 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qdesktopservices.h"
+
+#ifndef QT_NO_DESKTOPSERVICES
+
+#include <qdebug.h>
+
+#if defined(Q_WS_QWS)
+#include "qdesktopservices_qws.cpp"
+#elif defined(Q_WS_X11)
+#include "qdesktopservices_x11.cpp"
+#elif defined(Q_WS_WIN)
+#include "qdesktopservices_win.cpp"
+#elif defined(Q_WS_MAC)
+#include "qdesktopservices_mac.cpp"
+#elif defined(Q_OS_SYMBIAN)
+#include "qdesktopservices_s60.cpp"
+#endif
+
+#include <qhash.h>
+#include <qobject.h>
+#include <qcoreapplication.h>
+#include <qurl.h>
+#include <qmutex.h>
+
+QT_BEGIN_NAMESPACE
+
+class QOpenUrlHandlerRegistry : public QObject
+{
+    Q_OBJECT
+public:
+    inline QOpenUrlHandlerRegistry() : mutex(QMutex::Recursive) {}
+
+    QMutex mutex;
+
+    struct Handler
+    {
+        QObject *receiver;
+        QByteArray name;
+    };
+    typedef QHash<QString, Handler> HandlerHash;
+    HandlerHash handlers;
+
+public Q_SLOTS:
+    void handlerDestroyed(QObject *handler);
+
+};
+
+Q_GLOBAL_STATIC(QOpenUrlHandlerRegistry, handlerRegistry)
+
+void QOpenUrlHandlerRegistry::handlerDestroyed(QObject *handler)
+{
+    HandlerHash::Iterator it = handlers.begin();
+    while (it != handlers.end()) {
+        if (it->receiver == handler) {
+            it = handlers.erase(it);
+        } else {
+            ++it;
+        }
+    }
+}
+
+/*!
+    \class QDesktopServices
+    \brief The QDesktopServices class provides methods for accessing common desktop services.
+    \since 4.2
+    \ingroup desktop
+
+    Many desktop environments provide services that can be used by applications to
+    perform common tasks, such as opening a web page, in a way that is both consistent
+    and takes into account the user's application preferences.
+
+    This class contains functions that provide simple interfaces to these services
+    that indicate whether they succeeded or failed.
+
+    The openUrl() function is used to open files located at arbitrary URLs in external
+    applications. For URLs that correspond to resources on the local filing system
+    (where the URL scheme is "file"), a suitable application will be used to open the
+    file; otherwise, a web browser will be used to fetch and display the file.
+
+    The user's desktop settings control whether certain executable file types are
+    opened for browsing, or if they are executed instead. Some desktop environments
+    are configured to prevent users from executing files obtained from non-local URLs,
+    or to ask the user's permission before doing so.
+
+    \section1 URL Handlers
+
+    The behavior of the openUrl() function can be customized for individual URL
+    schemes to allow applications to override the default handling behavior for
+    certain types of URLs.
+
+    The dispatch mechanism allows only one custom handler to be used for each URL
+    scheme; this is set using the setUrlHandler() function. Each handler is
+    implemented as a slot which accepts only a single QUrl argument.
+
+    The existing handlers for each scheme can be removed with the
+    unsetUrlHandler() function. This returns the handling behavior for the given
+    scheme to the default behavior.
+
+    This system makes it easy to implement a help system, for example. Help could be
+    provided in labels and text browsers using \gui{help://myapplication/mytopic}
+    URLs, and by registering a handler it becomes possible to display the help text
+    inside the application:
+
+    \snippet doc/src/snippets/code/src_gui_util_qdesktopservices.cpp 0
+
+    If inside the handler you decide that you can't open the requested
+    URL, you can just call QDesktopServices::openUrl() again with the
+    same argument, and it will try to open the URL using the
+    appropriate mechanism for the user's desktop environment.
+
+    \sa QSystemTrayIcon, QProcess
+*/
+
+/*!
+    Opens the given \a url in the appropriate Web browser for the user's desktop
+    environment, and returns true if successful; otherwise returns false.
+
+    If the URL is a reference to a local file (i.e., the URL scheme is "file") then
+    it will be opened with a suitable application instead of a Web browser.
+
+    The following example opens a file on the Windows file system residing on a path
+    that contains spaces:
+
+    \snippet doc/src/snippets/code/src_gui_util_qdesktopservices.cpp 2
+
+    If a \c mailto URL is specified, the user's e-mail client will be used to open a
+    composer window containing the options specified in the URL, similar to the way
+    \c mailto links are handled by a Web browser.
+
+    For example, the following URL contains a recipient (\c{user@foo.com}), a
+    subject (\c{Test}), and a message body (\c{Just a test}):
+
+    \snippet doc/src/snippets/code/src_gui_util_qdesktopservices.cpp 1
+
+    \warning Although many e-mail clients can send attachments and are
+    Unicode-aware, the user may have configured their client without these features.
+    Also, certain e-mail clients (e.g., Lotus Notes) have problems with long URLs.
+
+    \sa setUrlHandler()
+*/
+bool QDesktopServices::openUrl(const QUrl &url)
+{
+    QOpenUrlHandlerRegistry *registry = handlerRegistry();
+    QMutexLocker locker(&registry->mutex);
+    static bool insideOpenUrlHandler = false;
+
+    if (!insideOpenUrlHandler) {
+        QOpenUrlHandlerRegistry::HandlerHash::ConstIterator handler = registry->handlers.constFind(url.scheme());
+        if (handler != registry->handlers.constEnd()) {
+            insideOpenUrlHandler = true;
+            bool result = QMetaObject::invokeMethod(handler->receiver, handler->name.constData(), Qt::DirectConnection, Q_ARG(QUrl, url));
+            insideOpenUrlHandler = false;
+            return result; // ### support bool slot return type
+        }
+    }
+
+    bool result;
+    if (url.scheme() == QLatin1String("file"))
+        result = openDocument(url);
+    else
+        result = launchWebBrowser(url);
+
+    return result;
+}
+
+/*!
+    Sets the handler for the given \a scheme to be the handler \a method provided by
+    the \a receiver object.
+
+    This function provides a way to customize the behavior of openUrl(). If openUrl()
+    is called with a URL with the specified \a scheme then the given \a method on the
+    \a receiver object is called instead of QDesktopServices launching an external
+    application.
+
+    The provided method must be implemented as a slot that only accepts a single QUrl
+    argument.
+
+    If setUrlHandler() is used to set a new handler for a scheme which already
+    has a handler, the existing handler is simply replaced with the new one.
+    Since QDesktopServices does not take ownership of handlers, no objects are
+    deleted when a handler is replaced.
+
+    Note that the handler will always be called from within the same thread that
+    calls QDesktopServices::openUrl().
+
+    \sa openUrl(), unsetUrlHandler()
+*/
+void QDesktopServices::setUrlHandler(const QString &scheme, QObject *receiver, const char *method)
+{
+    QOpenUrlHandlerRegistry *registry = handlerRegistry();
+    QMutexLocker locker(&registry->mutex);
+    if (!receiver) {
+        registry->handlers.remove(scheme);
+        return;
+    }
+    QOpenUrlHandlerRegistry::Handler h;
+    h.receiver = receiver;
+    h.name = method;
+    registry->handlers.insert(scheme, h);
+    QObject::connect(receiver, SIGNAL(destroyed(QObject*)),
+                     registry, SLOT(handlerDestroyed(QObject*)));
+}
+
+/*!
+    Removes a previously set URL handler for the specified \a scheme.
+
+    \sa setUrlHandler()
+*/
+void QDesktopServices::unsetUrlHandler(const QString &scheme)
+{
+    setUrlHandler(scheme, 0, 0);
+}
+
+/*!
+    \enum QDesktopServices::StandardLocation
+    \since 4.4
+
+    This enum describes the different locations that can be queried by
+    QDesktopServices::storageLocation and QDesktopServices::displayName.
+
+    \value DesktopLocation Returns the user's desktop directory.
+    \value DocumentsLocation Returns the user's document.
+    \value FontsLocation Returns the user's fonts.
+    \value ApplicationsLocation Returns the user's applications.
+    \value MusicLocation Returns the users music.
+    \value MoviesLocation Returns the user's movies.
+    \value PicturesLocation Returns the user's pictures.
+    \value TempLocation Returns the system's temporary directory.
+    \value HomeLocation Returns the user's home directory.
+    \value DataLocation Returns a directory location where persistent
+           application data can be stored. QCoreApplication::applicationName
+           and QCoreApplication::organizationName should work on all
+           platforms.
+    \value CacheLocation Returns a directory location where user-specific
+           non-essential (cached) data should be written.
+
+    \sa storageLocation() displayName()
+*/
+
+/*!
+    \fn QString QDesktopServices::storageLocation(StandardLocation type)
+    \since 4.4
+
+    Returns the default system directory where files of \a type belong, or an empty string
+    if the location cannot be determined.
+
+    \note The storage location returned can be a directory that does not exist; i.e., it
+    may need to be created by the system or the user.
+
+    \note On Symbian OS, ApplicationsLocation always point /sys/bin folder on the same drive
+    with executable. FontsLocation always points to folder on ROM drive. Symbian OS does not
+    have desktop concept, DesktopLocation returns same path as DocumentsLocation.
+    Rest of the standard locations point to folder on same drive with executable, except
+    that if executable is in ROM the folder from C drive is returned.
+
+    \note On Mac OS X, DataLocation does not include QCoreApplication::organizationName.
+    Use code like this to add it:
+
+    \code
+    QString location = QDesktopServices::storageLocation(QDesktopServices::DataLocation);
+    #ifdef Q_WS_MAC
+        location.insert(location.count() - QCoreApplication::applicationName().count(),
+            QCoreApplication::organizationName() + "/");
+    #endif
+    \endcode
+*/
+
+/*!
+    \fn QString QDesktopServices::displayName(StandardLocation type)
+
+    Returns a localized display name for the given location \a type or
+    an empty QString if no relevant location can be found.
+*/
+
+QT_END_NAMESPACE
+
+#include "qdesktopservices.moc"
+
+#endif // QT_NO_DESKTOPSERVICES