QMediaPlaylist Class

The QMediaPlaylist class provides a list of media content to play. More...

Header:	#include <QMediaPlaylist>
qmake:	QT += multimedia
Inherits:	QObject and QMediaBindableInterface

• List of all members, including inherited members

Public Types

enum	Error { NoError, FormatError, FormatNotSupportedError, NetworkError, AccessDeniedError }
enum	PlaybackMode { CurrentItemOnce, CurrentItemInLoop, Sequential, Loop, Random }

Properties

• currentIndex : int
• currentMedia : const QMediaContent
• playbackMode : QMediaPlaylist::PlaybackMode

Public Functions

	QMediaPlaylist(QObject *parent = nullptr)
virtual	~QMediaPlaylist()
bool	addMedia(const QMediaContent &content)
bool	addMedia(const QList<QMediaContent> &items)
bool	clear()
int	currentIndex() const
QMediaContent	currentMedia() const
QMediaPlaylist::Error	error() const
QString	errorString() const
bool	insertMedia(int pos, const QMediaContent &content)
bool	insertMedia(int pos, const QList<QMediaContent> &items)
bool	isEmpty() const
bool	isReadOnly() const
void	load(const QNetworkRequest &request, const char *format = nullptr)
void	load(const QUrl &location, const char *format = nullptr)
void	load(QIODevice *device, const char *format = nullptr)
QMediaContent	media(int index) const
int	mediaCount() const
bool	moveMedia(int from, int to)
int	nextIndex(int steps = 1) const
QMediaPlaylist::PlaybackMode	playbackMode() const
int	previousIndex(int steps = 1) const
bool	removeMedia(int pos)
bool	removeMedia(int start, int end)
bool	save(const QUrl &location, const char *format = nullptr)
bool	save(QIODevice *device, const char *format)
void	setPlaybackMode(QMediaPlaylist::PlaybackMode mode)

Reimplemented Public Functions

virtual QMediaObject *

mediaObject() const override

Public Slots

void	next()
void	previous()
void	setCurrentIndex(int playlistPosition)
void	shuffle()

Signals

void	currentIndexChanged(int position)
void	currentMediaChanged(const QMediaContent &content)
void	loadFailed()
void	loaded()
void	mediaAboutToBeInserted(int start, int end)
void	mediaAboutToBeRemoved(int start, int end)
void	mediaChanged(int start, int end)
void	mediaInserted(int start, int end)
void	mediaRemoved(int start, int end)
void	playbackModeChanged(QMediaPlaylist::PlaybackMode mode)

Detailed Description

QMediaPlaylist is intended to be used with other media objects, like QMediaPlayer.

QMediaPlaylist allows to access the service intrinsic playlist functionality if available, otherwise it provides the local memory playlist implementation.

playlist = new QMediaPlaylist;
playlist->addMedia(QUrl("http://example.com/movie1.mp4"));
playlist->addMedia(QUrl("http://example.com/movie2.mp4"));
playlist->addMedia(QUrl("http://example.com/movie3.mp4"));
playlist->setCurrentIndex(1);

player = new QMediaPlayer;
player->setPlaylist(playlist);

videoWidget = new QVideoWidget;
player->setVideoOutput(videoWidget);
videoWidget->show();

player->play();

Depending on playlist source implementation, most of the playlist mutating operations can be asynchronous.

See also QMediaContent.

Member Type Documentation

enum QMediaPlaylist::Error

This enum describes the QMediaPlaylist error codes.

Constant	Value	Description
QMediaPlaylist::NoError	0	No errors.
QMediaPlaylist::FormatError	1	Format error.
QMediaPlaylist::FormatNotSupportedError	2	Format not supported.
QMediaPlaylist::NetworkError	3	Network error.
QMediaPlaylist::AccessDeniedError	4	Access denied error.

enum QMediaPlaylist::PlaybackMode

The QMediaPlaylist::PlaybackMode describes the order items in playlist are played.

Constant	Value	Description
QMediaPlaylist::CurrentItemOnce	0	The current item is played only once.
QMediaPlaylist::CurrentItemInLoop	1	The current item is played repeatedly in a loop.
QMediaPlaylist::Sequential	2	Playback starts from the current and moves through each successive item until the last is reached and then stops. The next item is a null item when the last one is currently playing.
QMediaPlaylist::Loop	3	Playback restarts at the first item after the last has finished playing.
QMediaPlaylist::Random	4	Play items in random order.

Member Function Documentation

QMediaPlaylist::QMediaPlaylist(QObject *parent = nullptr)

Create a new playlist object with the given parent.

[signal] void QMediaPlaylist::currentIndexChanged(int position)

Signal emitted when playlist position changed to position.

Note: Notifier signal for property currentIndex.

[signal] void QMediaPlaylist::currentMediaChanged(const QMediaContent &content)

Signal emitted when current media changes to content.

Note: Notifier signal for property currentMedia.

[signal] void QMediaPlaylist::loadFailed()

Signal emitted if failed to load playlist.

[signal] void QMediaPlaylist::loaded()

Signal emitted when playlist finished loading.

[signal] void QMediaPlaylist::mediaAboutToBeInserted(int start, int end)

Signal emitted when items are to be inserted at start and ending at end.

[signal] void QMediaPlaylist::mediaAboutToBeRemoved(int start, int end)

Signal emitted when item are to be deleted at start and ending at end.

[signal] void QMediaPlaylist::mediaChanged(int start, int end)

This signal is emitted after media has been changed in the playlist between start and end positions inclusive.

[signal] void QMediaPlaylist::mediaInserted(int start, int end)

This signal is emitted after media has been inserted into the playlist. The new items are those between start and end inclusive.

[signal] void QMediaPlaylist::mediaRemoved(int start, int end)

This signal is emitted after media has been removed from the playlist. The removed items are those between start and end inclusive.

[slot] void QMediaPlaylist::next()

Advance to the next media content in playlist.

[signal] void QMediaPlaylist::playbackModeChanged(QMediaPlaylist::PlaybackMode mode)

Signal emitted when playback mode changed to mode.

Note: Notifier signal for property playbackMode.

[slot] void QMediaPlaylist::previous()

Return to the previous media content in playlist.

[slot] void QMediaPlaylist::setCurrentIndex(int playlistPosition)

Activate media content from playlist at position playlistPosition.

Note: Setter function for property currentIndex.

See also currentIndex().

[slot] void QMediaPlaylist::shuffle()

Shuffle items in the playlist.

[virtual] QMediaPlaylist::~QMediaPlaylist()

Destroys the playlist.

bool QMediaPlaylist::addMedia(const QMediaContent &content)

Append the media content to the playlist.

Returns true if the operation is successful, otherwise returns false.

bool QMediaPlaylist::addMedia(const QList<QMediaContent> &items)

Append multiple media content items to the playlist.

Returns true if the operation is successful, otherwise returns false.

bool QMediaPlaylist::clear()

Remove all the items from the playlist.

Returns true if the operation is successful, otherwise return false.

int QMediaPlaylist::currentIndex() const

Returns position of the current media content in the playlist.

Note: Getter function for property currentIndex.

See also setCurrentIndex().

QMediaContent QMediaPlaylist::currentMedia() const

Returns the current media content.

Note: Getter function for property currentMedia.

QMediaPlaylist::Error QMediaPlaylist::error() const

Returns the last error condition.

QString QMediaPlaylist::errorString() const

Returns the string describing the last error condition.

bool QMediaPlaylist::insertMedia(int pos, const QMediaContent &content)

Insert the media content to the playlist at position pos.

Returns true if the operation is successful, otherwise returns false.

bool QMediaPlaylist::insertMedia(int pos, const QList<QMediaContent> &items)

Insert multiple media content items to the playlist at position pos.

Returns true if the operation is successful, otherwise returns false.

bool QMediaPlaylist::isEmpty() const

Returns true if the playlist contains no items, otherwise returns false.

See also mediaCount().

bool QMediaPlaylist::isReadOnly() const

Returns true if the playlist can be modified, otherwise returns false.

See also mediaCount().

void QMediaPlaylist::load(const QNetworkRequest &request, const char *format = nullptr)

Load playlist using network request. If format is specified, it is used, otherwise format is guessed from playlist name and data.

New items are appended to playlist.

QMediaPlaylist::loaded() signal is emitted if playlist was loaded successfully, otherwise the playlist emits loadFailed().

void QMediaPlaylist::load(const QUrl &location, const char *format = nullptr)

Load playlist from location. If format is specified, it is used, otherwise format is guessed from location name and data.

New items are appended to playlist.

QMediaPlaylist::loaded() signal is emitted if playlist was loaded successfully, otherwise the playlist emits loadFailed().

void QMediaPlaylist::load(QIODevice *device, const char *format = nullptr)

Load playlist from QIODevice device. If format is specified, it is used, otherwise format is guessed from device data.

New items are appended to playlist.

QMediaPlaylist::loaded() signal is emitted if playlist was loaded successfully, otherwise the playlist emits loadFailed().

QMediaContent QMediaPlaylist::media(int index) const

Returns the media content at index in the playlist.

int QMediaPlaylist::mediaCount() const

Returns the number of items in the playlist.

See also isEmpty().

[override virtual] QMediaObject *QMediaPlaylist::mediaObject() const

Reimplements: QMediaBindableInterface::mediaObject() const.

Returns the QMediaObject instance that this QMediaPlaylist is bound too, or 0 otherwise.

bool QMediaPlaylist::moveMedia(int from, int to)

Move the item from position from to position to.

Returns true if the operation is successful, otherwise false.

This function was introduced in Qt 5.7.

int QMediaPlaylist::nextIndex(int steps = 1) const

Returns the index of the item, which would be current after calling next() steps times.

Returned value depends on the size of playlist, current position and playback mode.

See also QMediaPlaylist::playbackMode() and previousIndex().

int QMediaPlaylist::previousIndex(int steps = 1) const

Returns the index of the item, which would be current after calling previous() steps times.

See also QMediaPlaylist::playbackMode() and nextIndex().

bool QMediaPlaylist::removeMedia(int pos)

Remove the item from the playlist at position pos.

Returns true if the operation is successful, otherwise return false.

bool QMediaPlaylist::removeMedia(int start, int end)

Remove items in the playlist from start to end inclusive.

Returns true if the operation is successful, otherwise return false.

bool QMediaPlaylist::save(const QUrl &location, const char *format = nullptr)

Save playlist to location. If format is specified, it is used, otherwise format is guessed from location name.

Returns true if playlist was saved successfully, otherwise returns false.

bool QMediaPlaylist::save(QIODevice *device, const char *format)

Save playlist to QIODevice device using format format.

Returns true if playlist was saved successfully, otherwise returns false.