Add custom audio role API to QMediaPlayer

Allows use of audio roles beyond those known to Qt.

[ChangeLog][QMediaPlayer] Added customAudioRole string property to
enable use of audio roles beyond those available via the audioRole
enum property.

Change-Id: Id7ed5d7bc1af0c15910e699f25c97cfed2d48243
Reviewed-by: Christian Stromme <christian.stromme@qt.io>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>

7 files changed, 298 insertions, 6 deletions

diff --git a/src/multimedia/audio/qaudio.cpp b/src/multimedia/audio/qaudio.cpp
index dea9a05a5..82613270a 100644
--- a/src/multimedia/audio/qaudio.cpp
+++ b/src/multimedia/audio/qaudio.cpp
@@ -115,6 +115,7 @@ Q_CONSTRUCTOR_FUNCTION(qRegisterAudioMetaTypes)
     \value AccessibilityRole        For accessibility, such as with a screen reader
     \value SonificationRole         Sonification, such as with user interface sounds
     \value GameRole                 Game audio
+    \value CustomRole               The role is specified by QMediaPlayer::customAudioRole()
 
     \since 5.6
     \sa QMediaPlayer::setAudioRole()
@@ -347,6 +348,9 @@ QDebug operator<<(QDebug dbg, QAudio::Role role)
     case QAudio::VoiceCommunicationRole:
         dbg << "VoiceCommunicationRole";
         break;
+    case QAudio::CustomRole:
+        dbg << "CustomRole";
+        break;
     }
     return dbg;
 }
diff --git a/src/multimedia/audio/qaudio.h b/src/multimedia/audio/qaudio.h
index 2603d71d1..90a8c236f 100644
--- a/src/multimedia/audio/qaudio.h
+++ b/src/multimedia/audio/qaudio.h
@@ -68,7 +68,8 @@ namespace QAudio
         RingtoneRole,
         AccessibilityRole,
         SonificationRole,
-        GameRole
+        GameRole,
+        CustomRole
     };
 
     enum VolumeScale {
diff --git a/src/multimedia/controls/controls.pri b/src/multimedia/controls/controls.pri
index 7ab2e51c4..cfebe9777 100644
--- a/src/multimedia/controls/controls.pri
+++ b/src/multimedia/controls/controls.pri
@@ -37,7 +37,8 @@ PUBLIC_HEADERS += \
     controls/qmediaaudioprobecontrol.h \
     controls/qmediavideoprobecontrol.h \
     controls/qmediaavailabilitycontrol.h \
-    controls/qaudiorolecontrol.h
+    controls/qaudiorolecontrol.h \
+    controls/qcustomaudiorolecontrol.h
 
 PRIVATE_HEADERS += \
     controls/qmediaplaylistcontrol_p.h \
@@ -81,5 +82,5 @@ SOURCES += \
     controls/qaudioinputselectorcontrol.cpp \
     controls/qaudiooutputselectorcontrol.cpp \
     controls/qvideodeviceselectorcontrol.cpp \
-    controls/qaudiorolecontrol.cpp
-
+    controls/qaudiorolecontrol.cpp \
+    controls/qcustomaudiorolecontrol.cpp
diff --git a/src/multimedia/controls/qcustomaudiorolecontrol.cpp b/src/multimedia/controls/qcustomaudiorolecontrol.cpp
new file mode 100644
index 000000000..c01fc430c
--- /dev/null
+++ b/src/multimedia/controls/qcustomaudiorolecontrol.cpp
@@ -0,0 +1,117 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 QNX Software Systems. All rights reserved.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qmediacontrol_p.h"
+#include "qcustomaudiorolecontrol.h"
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QCustomAudioRoleControl
+    \inmodule QtMultimedia
+    \ingroup multimedia_control
+    \since 5.10
+
+    \brief The QCustomAudioRoleControl class provides control over the audio role of a media object.
+
+    If a QMediaService supports audio roles it may implement QCustomAudioRoleControl in order to
+    provide access to roles unknown to Qt.
+
+    The functionality provided by this control is exposed to application code through the
+    QMediaPlayer class.
+
+    The interface name of QCustomAudioRoleControl is \c org.qt-project.qt.customaudiorolecontrol/5.10 as
+    defined in QCustomAudioRoleControl_iid.
+
+    \sa QMediaService::requestControl(), QMediaPlayer
+*/
+
+/*!
+    \macro QCustomAudioRoleControl_iid
+
+    \c org.qt-project.qt.customaudiorolecontrol/5.10
+
+    Defines the interface name of the QCustomAudioRoleControl class.
+
+    \relates QCustomAudioRoleControl
+*/
+
+/*!
+    Construct a QCustomAudioRoleControl with the given \a parent.
+*/
+QCustomAudioRoleControl::QCustomAudioRoleControl(QObject *parent)
+    : QMediaControl(*new QMediaControlPrivate, parent)
+{
+}
+
+/*!
+    Destroys the audio role control.
+*/
+QCustomAudioRoleControl::~QCustomAudioRoleControl()
+{
+}
+
+/*!
+    \fn QAudio::Role QCustomAudioRoleControl::customAudioRole() const
+
+    Returns the audio role of the media played by the media service.
+*/
+
+/*!
+    \fn void QCustomAudioRoleControl::setCustomAudioRole(const QString &role)
+
+    Sets the audio \a role of the media played by the media service.
+*/
+
+/*!
+    \fn QStringList QCustomAudioRoleControl::supportedCustomAudioRoles() const
+
+    Returns a list of custom audio roles that the media service supports. An
+    empty list may indicate that the supported custom audio roles aren't known.
+    The list may not be complete.
+*/
+
+/*!
+    \fn void QCustomAudioRoleControl::customAudioRoleChanged(const QString &role)
+
+    Signal emitted when the audio \a role has changed.
+ */
+
+#include "moc_qcustomaudiorolecontrol.cpp"
+QT_END_NAMESPACE
diff --git a/src/multimedia/controls/qcustomaudiorolecontrol.h b/src/multimedia/controls/qcustomaudiorolecontrol.h
new file mode 100644
index 000000000..d699afe4e
--- /dev/null
+++ b/src/multimedia/controls/qcustomaudiorolecontrol.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 QNX Software Systems. All rights reserved.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QCUSTOMAUDIOROLECONTROL_H
+#define QCUSTOMAUDIOROLECONTROL_H
+
+#include <QtMultimedia/qmediacontrol.h>
+#include <QtMultimedia/qaudio.h>
+
+QT_BEGIN_NAMESPACE
+
+// Class forward declaration required for QDoc bug
+class QString;
+class QStringList;
+
+class Q_MULTIMEDIA_EXPORT QCustomAudioRoleControl : public QMediaControl
+{
+    Q_OBJECT
+
+public:
+    virtual ~QCustomAudioRoleControl();
+
+    virtual QString customAudioRole() const = 0;
+    virtual void setCustomAudioRole(const QString &role) = 0;
+
+    virtual QStringList supportedCustomAudioRoles() const = 0;
+
+Q_SIGNALS:
+    void customAudioRoleChanged(const QString &role);
+
+protected:
+    explicit QCustomAudioRoleControl(QObject *parent = nullptr);
+};
+
+#define QCustomAudioRoleControl_iid "org.qt-project.qt.customaudiorolecontrol/5.10"
+Q_MEDIA_DECLARE_CONTROL(QCustomAudioRoleControl, QCustomAudioRoleControl_iid)
+
+QT_END_NAMESPACE
+
+#endif // QCUSTOMAUDIOROLECONTROL_H
diff --git a/src/multimedia/playback/qmediaplayer.cpp b/src/multimedia/playback/qmediaplayer.cpp
index 16fdec8ea..e1fa31451 100644
--- a/src/multimedia/playback/qmediaplayer.cpp
+++ b/src/multimedia/playback/qmediaplayer.cpp
@@ -49,6 +49,7 @@
 #include <qmediaplaylistsourcecontrol_p.h>
 #include <qmedianetworkaccesscontrol.h>
 #include <qaudiorolecontrol.h>
+#include <qcustomaudiorolecontrol.h>
 
 #include <QtCore/qcoreevent.h>
 #include <QtCore/qmetaobject.h>
@@ -111,6 +112,7 @@ public:
         : provider(0)
         , control(0)
         , audioRoleControl(0)
+        , customAudioRoleControl(0)
         , playlist(0)
         , networkAccessControl(0)
         , state(QMediaPlayer::StoppedState)
@@ -124,6 +126,7 @@ public:
     QMediaServiceProvider *provider;
     QMediaPlayerControl* control;
     QAudioRoleControl *audioRoleControl;
+    QCustomAudioRoleControl *customAudioRoleControl;
     QString errorString;
 
     QPointer<QObject> videoOutput;
@@ -616,6 +619,15 @@ QMediaPlayer::QMediaPlayer(QObject *parent, QMediaPlayer::Flags flags):
             if (d->audioRoleControl) {
                 connect(d->audioRoleControl, &QAudioRoleControl::audioRoleChanged,
                         this, &QMediaPlayer::audioRoleChanged);
+
+                d->customAudioRoleControl = qobject_cast<QCustomAudioRoleControl *>(
+                        d->service->requestControl(QCustomAudioRoleControl_iid));
+                if (d->customAudioRoleControl) {
+                    connect(d->customAudioRoleControl,
+                            &QCustomAudioRoleControl::customAudioRoleChanged,
+                            this,
+                            &QMediaPlayer::customAudioRoleChanged);
+                }
             }
         }
         if (d->networkAccessControl != 0) {
@@ -641,6 +653,8 @@ QMediaPlayer::~QMediaPlayer()
             d->service->releaseControl(d->control);
         if (d->audioRoleControl)
             d->service->releaseControl(d->audioRoleControl);
+        if (d->customAudioRoleControl)
+            d->service->releaseControl(d->customAudioRoleControl);
 
         d->provider->releaseService(d->service);
     }
@@ -1150,8 +1164,13 @@ void QMediaPlayer::setAudioRole(QAudio::Role audioRole)
 {
     Q_D(QMediaPlayer);
 
-    if (d->audioRoleControl)
+    if (d->audioRoleControl) {
+        if (d->customAudioRoleControl != nullptr && d->audioRoleControl->audioRole() != audioRole) {
+            d->customAudioRoleControl->setCustomAudioRole(QString());
+        }
+
         d->audioRoleControl->setAudioRole(audioRole);
+    }
 }
 
 /*!
@@ -1172,6 +1191,48 @@ QList<QAudio::Role> QMediaPlayer::supportedAudioRoles() const
     return QList<QAudio::Role>();
 }
 
+QString QMediaPlayer::customAudioRole() const
+{
+    Q_D(const QMediaPlayer);
+
+    if (audioRole() != QAudio::CustomRole)
+        return QString();
+
+    if (d->customAudioRoleControl != nullptr)
+        return d->customAudioRoleControl->customAudioRole();
+
+    return QString();
+}
+
+void QMediaPlayer::setCustomAudioRole(const QString &audioRole)
+{
+    Q_D(QMediaPlayer);
+
+    if (d->customAudioRoleControl) {
+        Q_ASSERT(d->audioRoleControl);
+        setAudioRole(QAudio::CustomRole);
+        d->customAudioRoleControl->setCustomAudioRole(audioRole);
+    }
+}
+
+/*!
+    Returns a list of supported custom audio roles. An empty list may
+    indicate that the supported custom audio roles aren't known. The
+    list may not be complete.
+
+    \since 5.10
+    \sa customAudioRole
+*/
+QStringList QMediaPlayer::supportedCustomAudioRoles() const
+{
+    Q_D(const QMediaPlayer);
+
+    if (d->customAudioRoleControl)
+        return d->customAudioRoleControl->supportedCustomAudioRoles();
+
+    return QStringList();
+}
+
 // Enums
 /*!
     \enum QMediaPlayer::State
@@ -1279,6 +1340,14 @@ QList<QAudio::Role> QMediaPlayer::supportedAudioRoles() const
     \since 5.6
 */
 
+/*!
+    \fn void QMediaPlayer::customAudioRoleChanged(const QString &role)
+
+    Signals that the audio \a role of the media player has changed.
+
+    \since 5.10
+*/
+
 // Properties
 /*!
     \property QMediaPlayer::state
@@ -1461,11 +1530,30 @@ QList<QAudio::Role> QMediaPlayer::supportedAudioRoles() const
 
     The audio role must be set before calling setMedia().
 
+    customAudioRole is cleared when this property is set to anything other than
+    QAudio::CustomRole.
+
     \since 5.6
     \sa supportedAudioRoles()
 */
 
 /*!
+    \property QMediaPlayer::customAudioRole
+    \brief the role of the audio stream played by the media player.
+
+    It can be set to specify the type of audio being played when the backend supports
+    audio roles unknown to Qt. Specifying a role allows the system to make appropriate
+    decisions when it comes to volume, routing or post-processing.
+
+    The audio role must be set before calling setMedia().
+
+    audioRole is set to QAudio::CustomRole when this property is set.
+
+    \since 5.10
+    \sa supportedCustomAudioRoles()
+*/
+
+/*!
     \fn void QMediaPlayer::durationChanged(qint64 duration)
 
     Signal the duration of the content has changed to \a duration, expressed in milliseconds.
diff --git a/src/multimedia/playback/qmediaplayer.h b/src/multimedia/playback/qmediaplayer.h
index f23a94104..4e676a2d8 100644
--- a/src/multimedia/playback/qmediaplayer.h
+++ b/src/multimedia/playback/qmediaplayer.h
@@ -73,7 +73,8 @@ class Q_MULTIMEDIA_EXPORT QMediaPlayer : public QMediaObject
     Q_PROPERTY(qreal playbackRate READ playbackRate WRITE setPlaybackRate NOTIFY playbackRateChanged)
     Q_PROPERTY(State state READ state NOTIFY stateChanged)
     Q_PROPERTY(MediaStatus mediaStatus READ mediaStatus NOTIFY mediaStatusChanged)
-    Q_PROPERTY(QAudio::Role audioRole READ audioRole WRITE setAudioRole)
+    Q_PROPERTY(QAudio::Role audioRole READ audioRole WRITE setAudioRole NOTIFY audioRoleChanged)
+    Q_PROPERTY(QString customAudioRole READ customAudioRole WRITE setCustomAudioRole NOTIFY customAudioRoleChanged)
     Q_PROPERTY(QString error READ errorString)
     Q_ENUMS(State)
     Q_ENUMS(MediaStatus)
@@ -162,6 +163,9 @@ public:
     QAudio::Role audioRole() const;
     void setAudioRole(QAudio::Role audioRole);
     QList<QAudio::Role> supportedAudioRoles() const;
+    QString customAudioRole() const;
+    void setCustomAudioRole(const QString &audioRole);
+    QStringList supportedCustomAudioRoles() const;
 
 public Q_SLOTS:
     void play();
@@ -200,6 +204,7 @@ Q_SIGNALS:
     void playbackRateChanged(qreal rate);
 
     void audioRoleChanged(QAudio::Role role);
+    void customAudioRoleChanged(const QString &role);
 
     void error(QMediaPlayer::Error error);