QMetaDataReaderControl Class
The QMetaDataReaderControl class provides read access to the meta-data of a QMediaService's media. More...
| Header: | #include <QMetaDataReaderControl> |
| qmake: | QT += multimedia |
| Inherits: | QMediaControl. |
Public Functions
| ~QMetaDataReaderControl() | |
| virtual QStringList | availableMetaData() const = 0 |
| virtual bool | isMetaDataAvailable() const = 0 |
| virtual QVariant | metaData(const QString & key) const = 0 |
- 31 public functions inherited from QObject
Signals
| void | metaDataAvailableChanged(bool available) |
| void | metaDataChanged() |
| void | metaDataChanged(const QString & key, const QVariant & value) |
- 2 signals inherited from QObject
Protected Functions
| QMetaDataReaderControl(QObject * parent = 0) |
- 9 protected functions inherited from QObject
Macros
Additional Inherited Members
- 1 property inherited from QObject
- 1 public slot inherited from QObject
- 11 static public members inherited from QObject
Detailed Description
The QMetaDataReaderControl class provides read access to the meta-data of a QMediaService's media.
If a QMediaService can provide read or write access to the meta-data of its current media it will implement QMetaDataReaderControl. This control provides functions for both retrieving and setting meta-data values. Meta-data may be addressed by the keys defined in the QMediaMetaData namespace.
The functionality provided by this control is exposed to application code by the meta-data members of QMediaObject, and so meta-data access is potentially available in any of the media object classes. Any media service may implement QMetaDataReaderControl.
The interface name of QMetaDataReaderControl is org.qt-project.qt.metadatareadercontrol/5.0 as defined in QMetaDataReaderControl_iid.
See also QMediaService::requestControl() and QMediaObject.
Member Function Documentation
[protected] QMetaDataReaderControl::QMetaDataReaderControl(QObject * parent = 0)
Construct a QMetaDataReaderControl with parent. This class is meant as a base class for service specific meta data providers so this constructor is protected.
QMetaDataReaderControl::~QMetaDataReaderControl()
Destroy the meta-data object.
[pure virtual] QStringList QMetaDataReaderControl::availableMetaData() const
Returns a list of keys there is meta-data available for.
[pure virtual] bool QMetaDataReaderControl::isMetaDataAvailable() const
Identifies if meta-data is available from a media service.
Returns true if the meta-data is available and false otherwise.
[pure virtual] QVariant QMetaDataReaderControl::metaData(const QString & key) const
Returns the meta-data for the given key.
[signal] void QMetaDataReaderControl::metaDataAvailableChanged(bool available)
Signal the availability of meta-data has changed, available will be true if the multimedia object has meta-data.
[signal] void QMetaDataReaderControl::metaDataChanged()
Signal the changes of meta-data.
If multiple meta-data elements are changed, metaDataChanged(const QString &key, const QVariant &value) signal is emitted for each of them with metaDataChanged() changed emitted once.
[signal] void QMetaDataReaderControl::metaDataChanged(const QString & key, const QVariant & value)
Signal the changes of one meta-data element value with the given key.
Macro Documentation
QMetaDataReaderControl_iid
org.qt-project.qt.metadatareadercontrol/5.0
Defines the interface name of the QMetaDataReaderControl class.
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