Материал из Wiki.crossplatform.ru

Внимание: Актуальная версия перевода документации находится здесь

__NOTOC__

[править] QMovie Class Reference
^{[модуль QtGui ]}

The QMovie class is a convenience class for playing movies with QImageReader. Далее...

 #include <QMovie>

Inherits QObject.

• Список всех членов, включая унаследованные
• Поддерживаемые члены Qt 3

[править] Открытые типы

• enum CacheMode { CacheNone, CacheAll }
• enum MovieState { NotRunning, Paused, Running }

[править] Свойства

• cacheMode : CacheMode
• speed : int

• 1 свойство, унаследованное от QObject

[править] Открытые функции

• QMovie ( QObject * parent = 0 )
• QMovie ( QIODevice * device, const QByteArray & format = QByteArray(), QObject * parent = 0 )
• QMovie ( const QString & fileName, const QByteArray & format = QByteArray(), QObject * parent = 0 )
• ~QMovie ()
• QColor backgroundColor () const
• CacheMode cacheMode () const
• int currentFrameNumber () const
• QImage currentImage () const
• QPixmap currentPixmap () const
• QIODevice * device () const
• QString fileName () const
• QByteArray format () const
• int frameCount () const
• QRect frameRect () const
• bool isValid () const
• bool jumpToFrame ( int frameNumber )
• int loopCount () const
• int nextFrameDelay () const
• QSize scaledSize ()
• void setBackgroundColor ( const QColor & color )
• void setCacheMode ( CacheMode mode )
• void setDevice ( QIODevice * device )
• void setFileName ( const QString & fileName )
• void setFormat ( const QByteArray & format )
• void setScaledSize ( const QSize & size )
• int speed () const
• MovieState state () const

• 29 открытых функций, унаследованных от QObject

[править] Открытые слоты

• bool jumpToNextFrame ()
• void setPaused ( bool paused )
• void setSpeed ( int percentSpeed )
• void start ()
• void stop ()

• 1 открытый слот, унаследованный от QObject

[править] Сигналы

• void error ( QImageReader::ImageReaderError error )
• void finished ()
• void frameChanged ( int frameNumber )
• void resized ( const QSize & size )
• void started ()
• void stateChanged ( QMovie::MovieState state )
• void updated ( const QRect & rect )

• 1 сигнал, унаследованный от QObject

[править] Статические открытые члены

• QList<QByteArray> supportedFormats ()

• 5 статических открытых членов, унаследованных от QObject

[править] Дополнительные унаследованные члены

• 7 защищенных функций, унаследованных от QObject

[править] Подробное описание

The QMovie class is a convenience class for playing movies with QImageReader.

First, create a QMovie object by passing either the name of a file or a pointer to a QIODevice containing an animated image format to QMovie's constructor. You can call isValid() to check if the image data is valid, before starting the movie. To start the movie, call start(). QMovie will enter Running state, and emit started() and stateChanged(). To get the current state of the movie, call state().

To display the movie in your application, you can pass your QMovie object to QLabel::setMovie(). Пример:

 QLabel label;
 QMovie *movie = new QMovie("animations/fire.gif");
 
 label.setMovie(movie);
 movie->start();

Whenever a new frame is available in the movie, QMovie will emit updated(). If the size of the frame changes, resized() is emitted. You can call currentImage() or currentPixmap() to get a copy of the current frame. When the movie is done, QMovie emits finished(). If any error occurs during playback (i.e, the image file is corrupt), QMovie will emit error().

You can control the speed of the movie playback by calling setSpeed(), which takes the percentage of the original speed as an argument. Pause the movie by calling setPaused(true). QMovie will then enter Paused state and emit stateChanged(). If you call setPaused(false), QMovie will reenter Running state and start the movie again. To stop the movie, call stop().

Certain animation formats allow you to set the background color. You can call setBackgroundColor() to set the color, or backgroundColor() to retrieve the current background color.

currentFrameNumber() returns the sequence number of the current frame. The first frame in the animation has the sequence number 0. frameCount() returns the total number of frames in the animation, if the image format supports this. You can call loopCount() to get the number of times the movie should loop before finishing. nextFrameDelay() returns the number of milliseconds the current frame should be displayed.

QMovie can be instructed to cache frames of an animation by calling setCacheMode().

Call supportedFormats() for a list of formats that QMovie supports.

See also QLabel, QImageReader, and Movie Example.

[править] Описание типов

[править]

enum QMovie::CacheMode

This enum describes the different cache modes of QMovie.

[править]

enum QMovie::MovieState

This enum describes the different states of QMovie.

[править] Описание cвойств

[править]

cacheMode : CacheMode

This property holds the movie's cache mode.

Caching frames can be useful when the underlying animation format handler that QMovie relies on to decode the animation data does not support jumping to particular frames in the animation, or even "rewinding" the animation to the beginning (for looping). Furthermore, if the image data comes from a sequential device, it is not possible for the underlying animation handler to seek back to frames whose data has already been read (making looping altogether impossible). To aid in such situations, QMovie can be instructed to cache the frames, at the added memory cost of keeping the frames in memory for the lifetime of the QMovie.

Функции доступа:

• CacheMode cacheMode () const
• void setCacheMode ( CacheMode mode )

See also QMovie::CacheMode.

[править]

speed : int

This property holds the movie's speed.

The speed is measured in percentage of the original movie speed. The default speed is 100%. Пример:

 QMovie movie("racecar.gif");
 movie.setSpeed(200); // 2x speed

Функции доступа:

• int speed () const
• void setSpeed ( int percentSpeed )

[править] Описание функций-членов

[править]

QMovie::QMovie ( QObject * parent = 0 )

Constructs a QMovie object, passing the parent object to QObject's constructor.

See also setFileName(), setDevice(), and setFormat().

[править]

QMovie::QMovie ( QIODevice * device, const QByteArray & format = QByteArray(), QObject * parent = 0 )

Constructs a QMovie object. QMovie will use read image data from device, which it assumes is open and readable. If format is not empty, QMovie will use the image format format for decoding the image data. Otherwise, QMovie will attempt to guess the format.

The parent object is passed to QObject's constructor.

[править]

QMovie::QMovie ( const QString & fileName, const QByteArray & format = QByteArray(), QObject * parent = 0 )

Constructs a QMovie object. QMovie will use read image data from fileName. If format is not empty, QMovie will use the image format format for decoding the image data. Otherwise, QMovie will attempt to guess the format.

The parent object is passed to QObject's constructor.

[править]

QMovie::~QMovie ()

Destructs the QMovie object.

[править]

QColor QMovie::backgroundColor () const

Returns the background color of the movie. If no background color has been assigned, an invalid QColor is returned.

See also setBackgroundColor().

[править]

int QMovie::currentFrameNumber () const

Returns the sequence number of the current frame. The number of the first frame in the movie is 0.

[править]

QImage QMovie::currentImage () const

Returns the current frame as a QImage.

See also currentPixmap() and updated().

[править]

QPixmap QMovie::currentPixmap () const

Returns the current frame as a QPixmap.

See also currentImage() and updated().

[править]

QIODevice * QMovie::device () const

Returns the device QMovie reads image data from. If no device has currently been assigned, 0 is returned.

See also setDevice() and fileName().

[править]

void QMovie::error ( QImageReader::ImageReaderError error ) [signal]

This signal is emitted by QMovie when the error error occurred during playback. QMovie will stop the movie, and enter QMovie::NotRunning state.

[править]

QString QMovie::fileName () const

Returns the name of the file that QMovie reads image data from. If no file name has been assigned, or if the assigned device is not a file, an empty QString is returned.

See also setFileName() and device().

[править]

void QMovie::finished () [signal]

This signal is emitted when the movie has finished.

See also QMovie::stop().

[править]

QByteArray QMovie::format () const

Returns the format that QMovie uses when decoding image data. If no format has been assigned, an empty QByteArray() is returned.

See also setFormat().

[править]

void QMovie::frameChanged ( int frameNumber ) [signal]

This signal is emitted when the frame number has changed to frameNumber. You can call currentImage() or currentPixmap() to get a copy of the frame.

Эта функция была введена в Qt 4.1.

[править]

int QMovie::frameCount () const

Returns the number of frames in the movie.

Certain animation formats do not support this feature, in which case 0 is returned.

[править]

QRect QMovie::frameRect () const

Returns the rect of the last frame. If no frame has yet been updated, an invalid QRect is returned.

See also currentImage() and currentPixmap().

[править]

bool QMovie::isValid () const

Returns true if the movie is valid (e.g., the image data is readable and the image format is supported); otherwise returns false.

[править]

bool QMovie::jumpToFrame ( int frameNumber )

Jumps to frame number frameNumber. Возвращает true, если всё прошло успешно; в противном случае возвращает false.

[править]

bool QMovie::jumpToNextFrame () [slot]

Jumps to the next frame. Возвращает true, если всё прошло успешно; в противном случае возвращает false.

[править]

int QMovie::loopCount () const

Returns the number of times the movie will loop before it finishes. If the movie will only play once (no looping), loopCount returns 0. If the movie loops forever, loopCount returns -1.

Note that, if the image data comes from a sequential device (e.g. a socket), QMovie can only loop the movie if the cacheMode is set to QMovie::CacheAll.

[править]

int QMovie::nextFrameDelay () const

Returns the number of milliseconds QMovie will wait before updating the next frame in the animation.

[править]

void QMovie::resized ( const QSize & size ) [signal]

This signal is emitted when the current frame has been resized to size. This effect is sometimes used in animations as an alternative to replacing the frame. You can call currentImage() or currentPixmap() to get a copy of the updated frame.

[править]

QSize QMovie::scaledSize ()

Returns the scaled size of frames.

Эта функция была введена в Qt 4.1.

See also setScaledSize() and QImageReader::scaledSize().

[править]

void QMovie::setBackgroundColor ( const QColor & color )

For image formats that support it, this function sets the background color to color.

See also backgroundColor().

[править]

void QMovie::setDevice ( QIODevice * device )

Sets the current device to device. QMovie will read image data from this device when the movie is running.

See also device() and setFormat().

[править]

void QMovie::setFileName ( const QString & fileName )

Sets the name of the file that QMovie reads image data from, to fileName.

See also fileName(), setDevice(), and setFormat().

[править]

void QMovie::setFormat ( const QByteArray & format )

Sets the format that QMovie will use when decoding image data, to format. By default, QMovie will attempt to guess the format of the image data.

You can call supportedFormats() for the full list of formats QMovie supports.

See also format() and QImageReader::supportedImageFormats().

[править]

void QMovie::setPaused ( bool paused ) [slot]

If paused is true, QMovie will enter Paused state and emit stateChanged(Paused); otherwise it will enter Running state and emit stateChanged(Running).

See also paused() and state().

[править]

void QMovie::setScaledSize ( const QSize & size )

Sets the scaled frame size to size.

Эта функция была введена в Qt 4.1.

See also scaledSize() and QImageReader::setScaledSize().

[править]

void QMovie::start () [slot]

Starts the movie. QMovie will enter Running state, and start emitting updated() and resized() as the movie progresses.

If QMovie is in the Paused state, this function is equivalent to calling setPaused(false). If QMovie is already in the Running state, this function does nothing.

See also stop() and setPaused().

[править]

void QMovie::started () [signal]

This signal is emitted after QMovie::start() has been called, and QMovie has entered QMovie::Running state.

[править]

MovieState QMovie::state () const

Returns the current state of QMovie.

See also MovieState and stateChanged().

[править]

void QMovie::stateChanged ( QMovie::MovieState state ) [signal]

This signal is emitted every time the state of the movie changes. The new state is specified by state.

See also QMovie::state().

[править]

void QMovie::stop () [slot]

Stops the movie. QMovie enters NotRunning state, and stops emitting updated() and resized(). If start() is called again, the movie will restart from the beginning.

If QMovie is already in the NotRunning state, this function does nothing.

See also start() and setPaused().

[править]

QList< QByteArray> QMovie::supportedFormats () [static]

Returns the list of image formats supported by QMovie.

Эта функция была введена в Qt 4.1.

See also QImageReader::supportedImageFormats().

[править]

void QMovie::updated ( const QRect & rect ) [signal]

This signal is emitted when the rect rect in the current frame has been updated. You can call currentImage() or currentPixmap() to get a copy of the updated frame.