The QMediaService class provides a common base class for media service implementations. 更多...
| 头： | #include <QMediaService> |
| qmake: | QT += multimedia |
| 继承： | QObject |
该类已过时。 提供它是为使旧源代码能继续工作。强烈建议不要在新代码中使用它。
| virtual | ~QMediaService () |
| virtual void | releaseControl (QMediaControl * control ) = 0 |
| virtual QMediaControl * | requestControl (const char * interface ) = 0 |
| T | requestControl () |
| QMediaService (QObject * parent ) |
Media services provide implementations of the functionality promised by media objects, and allow multiple providers to implement a QMediaObject .
To provide the functionality of a QMediaObject media services implement QMediaControl interfaces. Services typically implement one core media control which provides the core feature of a media object, and some number of additional controls which provide either optional features of the media object, or features of a secondary media object or peripheral object.
A pointer to media service's QMediaControl implementation can be obtained by passing the control's interface name to the requestControl () 函数。
QMediaPlayerControl *control = qobject_cast<QMediaPlayerControl *>( mediaService->requestControl("org.qt-project.qt.mediaplayercontrol/5.0"));
Media objects can use services loaded dynamically from plug-ins or implemented statically within an applications. Plug-in based services should also implement the QMediaServiceProviderPlugin interface. Static services should implement the QMediaServiceProvider interface. In general, implementing a QMediaService is outside of the scope of this documentation and support on the relevant mailing lists or IRC channels should be sought.
另请参阅 QMediaObject and QMediaControl .
[protected]
QMediaService::
QMediaService
(
QObject
*
parent
)
Construct a media service with the given parent . This class is meant as a base class for Multimedia services so this constructor is protected.
[虚拟]
QMediaService::
~QMediaService
()
Destroys a media service.
[pure virtual]
void
QMediaService::
releaseControl
(
QMediaControl
*
control
)
Releases a control back to the service.
[pure virtual]
QMediaControl
*QMediaService::
requestControl
(const
char
*
interface
)
Returns a pointer to the media control implementing interface .
If the service does not implement the control, or if it is unavailable a null pointer is returned instead.
Controls must be returned to the service when no longer needed using the releaseControl () 函数。
Returns a pointer to the media control of type T implemented by a media service.
If the service does not implement the control, or if it is unavailable a null pointer is returned instead.
Controls must be returned to the service when no longer needed using the releaseControl () 函数。