QSystemTrayIcon uses D-Bus StatusNotifier on Linux when possible

Implementing org.kde.StatusNotifier DBus interface
http://www.freedesktop.org/wiki/Specifications/StatusNotifierItem/
as well as org.canonical.dbusmenu for the limited purpose of showing
the tray icon's context menu.  If a desktop environment (such as
KDE or Unity) has a StatusNotifierWatcher listening, then tray icon
information is sent to be displayed by the tray implementation
instead of being rendered directly in an XEmbed window.  This is
necessary because some modern tray implementations no longer provide
XEmbed "hosting".

[ChangeLog][QPA][Xcb] QSystemTrayIcon uses StatusNotifier D-Bus
protocol when the desktop environment supports it

Task-number: QTBUG-31762
Done-with: Marco Martin <mart@kde.org>
Change-Id: I3b1f744d621eefc7e9c61d1469460ebfcc77fc54
Reviewed-by: Jørgen Lind <jorgen.lind@theqtcompany.com>
Reviewed-by: Dmitry Shachnev <mitya57@gmail.com>

1 files changed, 260 insertions, 0 deletions

diff --git a/src/platformsupport/dbustray/qdbustrayicon.cpp b/src/platformsupport/dbustray/qdbustrayicon.cpp
new file mode 100644
index 0000000000..1c21da849c
--- /dev/null
+++ b/src/platformsupport/dbustray/qdbustrayicon.cpp
@@ -0,0 +1,260 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** 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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QT_NO_SYSTEMTRAYICON
+
+#include "qdbustrayicon_p.h"
+#include "qdbusmenuconnection_p.h"
+#include "qstatusnotifieritemadaptor_p.h"
+#include "qdbusmenuadaptor_p.h"
+#include "dbusmenu/qdbusplatformmenu_p.h"
+
+#include <qplatformmenu.h>
+#include <qstring.h>
+#include <qdebug.h>
+#include <qrect.h>
+#include <qloggingcategory.h>
+#include <qplatformintegration.h>
+#include <qplatformservices.h>
+#include <private/qguiapplication_p.h>
+
+QT_BEGIN_NAMESPACE
+
+Q_LOGGING_CATEGORY(qLcTray, "qt.qpa.tray")
+
+static const QString KDEItemFormat = QStringLiteral("org.kde.StatusNotifierItem-%1-%2");
+static const QString TempFileTemplate =  QDir::tempPath() + QStringLiteral("/qt-trayicon-XXXXXX.png");
+static int instanceCount = 0;
+
+/*!
+    \class QDBusTrayIcon
+    \internal
+*/
+
+QDBusTrayIcon::QDBusTrayIcon()
+    : m_dbusConnection(Q_NULLPTR)
+    , m_adaptor(new QStatusNotifierItemAdaptor(this))
+    , m_menuAdaptor(Q_NULLPTR)
+    , m_menu(Q_NULLPTR)
+    , m_instanceId(KDEItemFormat.arg(QCoreApplication::applicationPid()).arg(++instanceCount))
+    , m_category(QStringLiteral("ApplicationStatus"))
+    , m_defaultStatus(QStringLiteral("Active")) // be visible all the time.  QSystemTrayIcon has no API to control this.
+    , m_status(m_defaultStatus)
+    , m_tempIcon(Q_NULLPTR)
+    , m_tempAttentionIcon(Q_NULLPTR)
+{
+    qCDebug(qLcTray);
+    if (instanceCount == 1) {
+        QDBusMenuItem::registerDBusTypes();
+        qDBusRegisterMetaType<QXdgDBusImageStruct>();
+        qDBusRegisterMetaType<QXdgDBusImageVector>();
+        qDBusRegisterMetaType<QXdgDBusToolTipStruct>();
+    }
+    connect(this, SIGNAL(statusChanged(QString)), m_adaptor, SIGNAL(NewStatus(QString)));
+    connect(this, SIGNAL(tooltipChanged()), m_adaptor, SIGNAL(NewToolTip()));
+    connect(this, SIGNAL(iconChanged()), m_adaptor, SIGNAL(NewIcon()));
+    connect(this, SIGNAL(attention()), m_adaptor, SIGNAL(NewAttentionIcon()));
+    connect(this, SIGNAL(attention()), m_adaptor, SIGNAL(NewTitle()));
+    connect(&m_attentionTimer, SIGNAL(timeout()), this, SLOT(attentionTimerExpired()));
+    m_attentionTimer.setSingleShot(true);
+}
+
+QDBusTrayIcon::~QDBusTrayIcon()
+{
+}
+
+void QDBusTrayIcon::init()
+{
+    qCDebug(qLcTray) << "registering" << m_instanceId;
+    dBusConnection()->registerTrayIcon(this);
+}
+
+void QDBusTrayIcon::cleanup()
+{
+    qCDebug(qLcTray) << "unregistering" << m_instanceId;
+    dBusConnection()->unregisterTrayIcon(this);
+    delete m_dbusConnection;
+    m_dbusConnection = Q_NULLPTR;
+}
+
+void QDBusTrayIcon::activate(int x, int y)
+{
+    qCDebug(qLcTray) << x << y;
+    setStatus(QStringLiteral("Active"));
+}
+
+void QDBusTrayIcon::attentionTimerExpired()
+{
+    m_messageTitle = QString();
+    m_message = QString();
+    m_attentionIcon = QIcon();
+    emit attention();
+    emit tooltipChanged();
+    setStatus(m_defaultStatus);
+}
+
+void QDBusTrayIcon::setStatus(const QString &status)
+{
+    qCDebug(qLcTray) << status;
+    if (m_status == status)
+        return;
+    m_status = status;
+    emit statusChanged(m_status);
+}
+
+QTemporaryFile *QDBusTrayIcon::tempIcon(const QIcon &icon)
+{
+    // Hack for Unity, which doesn't handle icons sent across D-Bus:
+    // save the icon to a temp file and set the icon name to that filename.
+    static bool necessary = (QGuiApplicationPrivate::platformIntegration()->services()->desktopEnvironment().split(':').contains("UNITY"));
+    if (!necessary)
+        return Q_NULLPTR;
+    QTemporaryFile *ret = new QTemporaryFile(TempFileTemplate, this);
+    QSize tempSize;
+    Q_FOREACH (const QSize &size, icon.availableSizes())
+        if (size.width() > tempSize.width())
+            tempSize = size;
+    ret->open();
+    icon.pixmap(tempSize).save(ret);
+    ret->close();
+    return ret;
+}
+
+QDBusMenuConnection * QDBusTrayIcon::dBusConnection()
+{
+    if (!m_dbusConnection)
+        m_dbusConnection = new QDBusMenuConnection(this);
+    return m_dbusConnection;
+}
+
+void QDBusTrayIcon::updateIcon(const QIcon &icon)
+{
+    m_iconName = icon.name();
+    m_icon = icon;
+    if (m_iconName.isEmpty()) {
+        if (m_tempIcon)
+            delete m_tempIcon;
+        m_tempIcon = tempIcon(icon);
+        if (m_tempIcon)
+            m_iconName = m_tempIcon->fileName();
+    }
+    qCDebug(qLcTray) << m_iconName << icon.availableSizes();
+    emit iconChanged();
+}
+
+void QDBusTrayIcon::updateToolTip(const QString &tooltip)
+{
+    qCDebug(qLcTray) << tooltip;
+    m_tooltip = tooltip;
+    emit tooltipChanged();
+}
+
+QPlatformMenu *QDBusTrayIcon::createMenu() const
+{
+    qCDebug(qLcTray);
+    if (!m_menu)
+        const_cast<QDBusTrayIcon *>(this)->m_menu = new QDBusPlatformMenu();
+    return m_menu;
+}
+
+void QDBusTrayIcon::updateMenu(QPlatformMenu * menu)
+{
+    qCDebug(qLcTray) << menu;
+    if (!m_menu)
+        m_menu = qobject_cast<QDBusPlatformMenu *>(menu);
+    if (!m_menuAdaptor) {
+        m_menuAdaptor = new QDBusMenuAdaptor(m_menu);
+        // TODO connect(m_menu, , m_menuAdaptor, SIGNAL(ItemActivationRequested(int,uint)));
+        connect(m_menu, SIGNAL(propertiesUpdated(QDBusMenuItemList,QDBusMenuItemKeysList)),
+                m_menuAdaptor, SIGNAL(ItemsPropertiesUpdated(QDBusMenuItemList,QDBusMenuItemKeysList)));
+        connect(m_menu, SIGNAL(updated(uint,int)),
+                m_menuAdaptor, SIGNAL(LayoutUpdated(uint,int)));
+    }
+    m_menu->emitUpdated();
+}
+
+void QDBusTrayIcon::contextMenu(int x, int y)
+{
+    qCDebug(qLcTray) << x << y;
+}
+
+void QDBusTrayIcon::showMessage(const QString &title, const QString &msg, const QIcon &icon,
+                                QPlatformSystemTrayIcon::MessageIcon iconType, int msecs)
+{
+    m_messageTitle = title;
+    m_message = msg;
+    m_attentionIcon = icon;
+    switch (iconType) {
+    case Information:
+        m_attentionIconName = QStringLiteral("dialog-information");
+        break;
+    case Warning:
+        m_attentionIconName = QStringLiteral("dialog-warning");
+        break;
+    case Critical:
+        m_attentionIconName = QStringLiteral("dialog-error");
+        break;
+    default:
+        m_attentionIconName.clear();
+        break;
+    }
+    if (m_attentionIconName.isEmpty()) {
+        if (m_tempAttentionIcon)
+            delete m_tempAttentionIcon;
+        m_tempAttentionIcon = tempIcon(icon);
+        if (m_tempAttentionIcon)
+            m_attentionIconName = m_tempAttentionIcon->fileName();
+    }
+    qCDebug(qLcTray) << title << msg <<
+        QPlatformSystemTrayIcon::metaObject()->enumerator(
+            QPlatformSystemTrayIcon::staticMetaObject.indexOfEnumerator("MessageIcon")).valueToKey(iconType)
+        << m_attentionIconName << msecs;
+    setStatus(QStringLiteral("NeedsAttention"));
+    m_attentionTimer.start(msecs);
+    emit tooltipChanged();
+    emit attention();
+}
+
+bool QDBusTrayIcon::isSystemTrayAvailable() const
+{
+    QDBusMenuConnection * conn = const_cast<QDBusTrayIcon *>(this)->dBusConnection();
+
+    // If the KDE watcher service is registered, we must be on a desktop
+    // where a StatusNotifier-conforming system tray exists.
+    qCDebug(qLcTray) << conn->isWatcherRegistered();
+    return conn->isWatcherRegistered();
+}
+
+QT_END_NAMESPACE
+#endif //QT_NO_SYSTEMTRAYICON
+