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    41 

    42 

    43 #include "qaudiosystemplugin.h"

    44 

    45 QT_BEGIN_NAMESPACE

    46 

    47 /*!

    48     \class QAudioSystemPlugin

    49     \brief The QAudioSystemPlugin class provides an abstract base for audio plugins.

    50 

    51     \ingroup multimedia

    52     \inmodule QtMultimedia

    53     \internal

    54 

    55     Writing a audio plugin is achieved by subclassing this base class,

    56     reimplementing the pure virtual functions keys(), availableDevices(),

    57     createInput(), createOutput() and createDeviceInfo() then exporting

    58     the class with the Q_EXPORT_PLUGIN2() macro.

    59 

    60     Unit tests are available to help in debugging new plugins.

    61 

    62     \sa QAbstractAudioDeviceInfo, QAbstractAudioOutput, QAbstractAudioInput

    63 

    64     Qt supports win32, linux(alsa) and Mac OS X standard (builtin to the

    65     QtMultimedia library at compile time).

    66 

    67     You can support other backends other than these predefined ones by

    68     creating a plugin subclassing QAudioSystemPlugin, QAbstractAudioDeviceInfo,

    69     QAbstractAudioOutput and QAbstractAudioInput.

    70 

    71     Add "default" to your list of keys() available to override the default

    72     audio device to be provided by your plugin.

    73 

    74     -audio-backend configure option will force compiling in of the builtin backend

    75     into the QtMultimedia library at compile time. This is automatic by default

    76     and will only be compiled into the library if the dependencies are installed.

    77     eg. alsa-devel package installed for linux.

    78 

    79     If the builtin backend is not compiled into the QtMultimedia library and

    80     no audio plugins are available a fallback dummy backend will be used.

    81     This should print out warnings if this is the case when you try and use QAudioInput or QAudioOutput. To fix this problem

    82     reconfigure Qt using -audio-backend or create your own plugin with a default

    83     key to always override the dummy fallback. The easiest way to determine

    84     if you have only a dummy backend is to get a list of available audio devices.

    85 

    86     QAudioDeviceInfo::availableDevices(QAudio::AudioOutput).size() = 0 (dummy backend)

    87 */

    88 

    89 /*!

    90     Construct a new audio plugin with \a parent.

    91     This is invoked automatically by the Q_EXPORT_PLUGIN2() macro.

    92 */

    93 

    94 QAudioSystemPlugin::QAudioSystemPlugin(QObject* parent) :

    95     QObject(parent)

    96 {}

    97 

    98 /*!

    99    Destroy the audio plugin

   100 

   101    You never have to call this explicitly. Qt destroys a plugin automatically when it is no longer used.

   102 */

   103 

   104 QAudioSystemPlugin::~QAudioSystemPlugin()

   105 {}

   106 

   107 /*!

   108     \fn QStringList QAudioSystemPlugin::keys() const

   109     Returns the list of device identifiers this plugin supports.

   110 */

   111 

   112 /*!

   113     \fn QList<QByteArray> QAudioSystemPlugin::availableDevices(QAudio::Mode mode) const

   114     Returns a list of available audio devices for \a mode

   115 */

   116 

   117 /*!

   118     \fn QAbstractAudioInput* QAudioSystemPlugin::createInput(const QByteArray& device)

   119     Returns a pointer to a QAbstractAudioInput created using \a device identifier

   120 */

   121 

   122 /*!

   123     \fn QAbstractAudioOutput* QAudioSystemPlugin::createOutput(const QByteArray& device)

   124     Returns a pointer to a QAbstractAudioOutput created using \a device identifier

   125 

   126 */

   127 

   128 /*!

   129     \fn QAbstractAudioDeviceInfo* QAudioSystemPlugin::createDeviceInfo(const QByteArray& device, QAudio::Mode mode)

   130     Returns a pointer to a QAbstractAudioDeviceInfo created using \a device and \a mode

   131 

   132 */

   133 

   134 

   135 QT_END_NAMESPACE