New QCameraInfo class.

The class allows to get the list of available cameras on the system as
well as getting some static information about them such as their unique
ID, display name, physical position and sensor orientation.

This makes QCamera::availableDevices() and QCamera::deviceDescription()
obsolete.

This patch contains the API, documentation and auto-tests but not the
actual implementation by each backend (except for retrieving the default
camera device).

[ChangeLog][QtMultimedia] Added new QCameraInfo class
[ChangeLog][QtMultimedia] QCamera: availableDevices() and
deviceDescription() are deprecated, use QCameraInfo instead

Change-Id: I64fd65729ab26a789468979ed5444ee90bb82cd0
Reviewed-by: Christian Stromme <christian.stromme@digia.com>

src/plugins/android/src/mediacapture/qandroidvideodeviceselectorcontrol.cpp

@@ -46,6 +46,7 @@
 
 QT_BEGIN_NAMESPACE
 
+QByteArray QAndroidVideoDeviceSelectorControl::m_defaultDevice;
 QList<QByteArray> QAndroidVideoDeviceSelectorControl::m_names;
 QStringList QAndroidVideoDeviceSelectorControl::m_descriptions;
 
@@ -99,6 +100,7 @@ void QAndroidVideoDeviceSelectorControl::setSelectedDevice(int index)
 
 void QAndroidVideoDeviceSelectorControl::update()
 {
+    m_defaultDevice.clear();
     m_names.clear();
     m_descriptions.clear();
 
@@ -127,6 +129,17 @@ void QAndroidVideoDeviceSelectorControl::update()
             break;
         }
     }
+
+    if (!m_names.isEmpty())
+        m_defaultDevice = m_names.first();
+}
+
+QByteArray QAndroidVideoDeviceSelectorControl::defaultDeviceName()
+{
+    if (m_names.isEmpty())
+        update();
+
+    return m_defaultDevice;
 }
 
 QList<QByteArray> QAndroidVideoDeviceSelectorControl::availableDevices()

src/plugins/android/src/mediacapture/qandroidvideodeviceselectorcontrol.h

@@ -66,6 +66,7 @@ public:
 
     void setSelectedDevice(int index);
 
+    static QByteArray defaultDeviceName();
     static QList<QByteArray> availableDevices();
     static QString availableDeviceDescription(const QByteArray &device);
 
@@ -73,6 +74,7 @@ private:
     static void update();
 
     int m_selectedDevice;
+    static QByteArray m_defaultDevice;
     static QList<QByteArray> m_names;
     static QStringList m_descriptions;
 

src/plugins/android/src/qandroidmediaserviceplugin.cpp

@@ -96,6 +96,14 @@ QMediaServiceProviderHint::Features QAndroidMediaServicePlugin::supportedFeature
     return QMediaServiceProviderHint::Features();
 }
 
+QByteArray QAndroidMediaServicePlugin::defaultDevice(const QByteArray &service) const
+{
+    if (service == Q_MEDIASERVICE_CAMERA)
+        return QAndroidVideoDeviceSelectorControl::defaultDeviceName();
+
+    return QByteArray();
+}
+
 QList<QByteArray> QAndroidMediaServicePlugin::devices(const QByteArray &service) const
 {
     if (service == Q_MEDIASERVICE_CAMERA)

src/plugins/android/src/qandroidmediaserviceplugin.h

@@ -49,10 +49,12 @@ QT_BEGIN_NAMESPACE
 class QAndroidMediaServicePlugin
         : public QMediaServiceProviderPlugin
         , public QMediaServiceSupportedDevicesInterface
+        , public QMediaServiceDefaultDeviceInterface
         , public QMediaServiceFeaturesInterface
 {
     Q_OBJECT
     Q_INTERFACES(QMediaServiceSupportedDevicesInterface)
+    Q_INTERFACES(QMediaServiceDefaultDeviceInterface)
     Q_INTERFACES(QMediaServiceFeaturesInterface)
     Q_PLUGIN_METADATA(IID "org.qt-project.qt.mediaserviceproviderfactory/5.0"
                       FILE "android_mediaservice.json")
@@ -66,6 +68,7 @@ public:
 
     QMediaServiceProviderHint::Features supportedFeatures(const QByteArray &service) const Q_DECL_OVERRIDE;
 
+    QByteArray defaultDevice(const QByteArray &service) const;
     QList<QByteArray> devices(const QByteArray &service) const;
     QString deviceDescription(const QByteArray &service, const QByteArray &device);
 };