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QMediaControl Class

The QMediaControl class provides a base interface for media service controls. More...

Header: #include <QMediaControl>
qmake: QT += multimedia
Inherits: QObject
Inherited By:

QAudioDecoderControl, QAudioEncoderSettingsControl, QAudioInputSelectorControl, QAudioOutputSelectorControl, QAudioRoleControl, QCameraCaptureBufferFormatControl, QCameraCaptureDestinationControl, QCameraControl, QCameraExposureControl, QCameraFeedbackControl, QCameraFlashControl, QCameraFocusControl, QCameraImageCaptureControl, QCameraImageProcessingControl, QCameraInfoControl, QCameraLocksControl, QCameraViewfinderSettingsControl, QCameraViewfinderSettingsControl2, QCameraZoomControl, QCustomAudioRoleControl, QImageEncoderControl, QMediaAudioProbeControl, QMediaAvailabilityControl, QMediaContainerControl, QMediaGaplessPlaybackControl, QMediaNetworkAccessControl, QMediaPlayerControl, QMediaRecorderControl, QMediaStreamsControl, QMediaVideoProbeControl, QMetaDataReaderControl, QMetaDataWriterControl, QRadioDataControl, QRadioTunerControl, QVideoDeviceSelectorControl, QVideoEncoderSettingsControl, QVideoRendererControl, QVideoWidgetControl, and QVideoWindowControl

Public Functions

virtual ~QMediaControl()
  • 34 public functions inherited from QObject

Protected Functions

QMediaControl(QObject *parent = nullptr)
  • 9 protected functions inherited from QObject

Macros

Q_MEDIA_DECLARE_CONTROL(Class, IId)

Additional Inherited Members

  • 1 property inherited from QObject
  • 1 public slot inherited from QObject
  • 2 signals inherited from QObject
  • 1 public variable inherited from QObject
  • 10 static public members inherited from QObject
  • 2 protected variables inherited from QObject

Detailed Description

The QMediaControl class provides a base interface for media service controls.

Media controls provide an interface to individual features provided by a media service. Most services implement a principal control which exposes the core functionality of the service and a number of optional controls which expose any additional functionality.

A pointer to a control implemented by a media service can be obtained using the QMediaService::requestControl() member of QMediaService. If the service doesn't implement a control it will instead return a null pointer.

QMediaPlayerControl *control = qobject_cast<QMediaPlayerControl *>(
        mediaService->requestControl("org.qt-project.qt.mediaplayercontrol/5.0"));

Alternatively if the IId of the control has been declared using Q_MEDIA_DECLARE_CONTROL the template version of QMediaService::requestControl() can be used to request the service without explicitly passing the IId or using qobject_cast().

QMediaPlayerControl *control = mediaService->requestControl<QMediaPlayerControl *>();

Most application code will not interface directly with a media service's controls, instead the QMediaObject which owns the service acts as an intermediary between one or more controls and the application.

See also QMediaService and QMediaObject.

Member Function Documentation

[protected] QMediaControl::QMediaControl(QObject *parent = nullptr)

Constructs a media control with the given parent.

[virtual] QMediaControl::~QMediaControl()

Destroys a media control.

Macro Documentation

Q_MEDIA_DECLARE_CONTROL(Class, IId)

The Q_MEDIA_DECLARE_CONTROL macro declares an IId for a Class that inherits from QMediaControl.

Declaring an IId for a QMediaControl allows an instance of that control to be requested from QMediaService::requestControl() without explicitly passing the IId.

QMediaPlayerControl *control = mediaService->requestControl<QMediaPlayerControl *>();

See also QMediaService::requestControl().

© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-5/qmediacontrol.html