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QMetaDataControl Class Reference

The QMetaDataControl class provides access to the meta-data of a QMediaService's media. More...

    #include <QMetaDataControl>

This class is under development and is subject to change.

Inherits QMediaControl.


Public Functions

~QMetaDataControl ()
virtual QStringList availableExtendedMetaData () const = 0
virtual QList<QtMedia::MetaData> availableMetaData () const = 0
virtual QVariant extendedMetaData ( const QString & key ) const = 0
virtual bool isMetaDataAvailable () const = 0
virtual bool isWritable () const = 0
virtual QVariant metaData ( QtMedia::MetaData key ) const = 0
virtual void setExtendedMetaData ( const QString & key, const QVariant & value ) = 0
virtual void setMetaData ( QtMedia::MetaData key, const QVariant & value ) = 0

Signals

void metaDataAvailableChanged ( bool available )
void metaDataChanged ()
void writableChanged ( bool writable )

Protected Functions

QMetaDataControl ( QObject * parent = 0 )

Macros

QMetaDataControl_iid

Additional Inherited Members


Detailed Description

The QMetaDataControl class provides 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 QMetaDataControl. This control provides functions for both retrieving and setting meta-data values. Meta-data may be addressed by the well defined keys in the QtMedia::MetaData enumeration using the metaData() functions, or by string keys using the extendedMetaData() functions.

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 QMetaDataControl.

The interface name of QMetaDataControl is com.nokia.Qt.QMetaDataControl/1.0 as defined in QMetaDataControl_iid.

See also QMediaService::control() and QMediaObject.


Member Function Documentation

QMetaDataControl::QMetaDataControl ( QObject * parent = 0 )   [protected]

Construct a QMetaDataControl with parent. This class is meant as a base class for service specific meta data providers so this constructor is protected.

QMetaDataControl::~QMetaDataControl ()

Destroy the meta-data object.

QStringList QMetaDataControl::availableExtendedMetaData () const   [pure virtual]

Returns a list of keys there is extended meta-data available for.

QList<QtMedia::MetaData> QMetaDataControl::availableMetaData () const   [pure virtual]

Returns a list of keys there is meta-data available for.

QVariant QMetaDataControl::extendedMetaData ( const QString & key ) const   [pure virtual]

Returns the metaData for an abitrary string key.

The valid selection of keys for extended meta-data is determined by the provider and the meaning and type may differ between providers.

See also setExtendedMetaData().

bool QMetaDataControl::isMetaDataAvailable () const   [pure virtual]

Identifies if meta-data is available from a media service.

Returns true if the meta-data is available and false otherwise.

bool QMetaDataControl::isWritable () const   [pure virtual]

Identifies if a media service's meta-data can be edited.

Returns true if the meta-data is writable and false otherwise.

QVariant QMetaDataControl::metaData ( QtMedia::MetaData key ) const   [pure virtual]

Returns the meta-data for the given key.

See also setMetaData().

void QMetaDataControl::metaDataAvailableChanged ( bool available )   [signal]

Signal the availability of meta-data has changed, available will be true if the multimedia object has meta-data.

void QMetaDataControl::metaDataChanged ()   [signal]

Signal the changes of meta-data.

void QMetaDataControl::setExtendedMetaData ( const QString & key, const QVariant & value )   [pure virtual]

Change the value of the meta-data element with an abitrary string key to value.

The valid selection of keys for extended meta-data is determined by the provider and the meaning and type may differ between providers.

See also extendedMetaData().

void QMetaDataControl::setMetaData ( QtMedia::MetaData key, const QVariant & value )   [pure virtual]

Sets the value of the meta-data element with the given key.

See also metaData().

void QMetaDataControl::writableChanged ( bool writable )   [signal]

Signal a change in the writable status of meta-data, writable will be true if meta-data elements can be added or adjusted.


Macro Documentation

QMetaDataControl_iid

com.nokia.Qt.QMetaDataControl/1.0

Defines the interface name of the QMetaDataControl class.


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Qt Mobility Project 1.0.0