Referencia de la Clase QPicture

The QPicture class is a paint device that records and replays QPainter commands. Más...

#include <qpicture.h>

Diagrama de herencias de QPicture

Lista de todos los miembros.

Clases
struct	QPicturePrivate
Métodos públicos
	QPicture (int formatVersion=-1)
	QPicture (const QPicture &)
	~QPicture ()
bool	isNull () const
uint	size () const
const char *	data () const
virtual void	setData (const char *data, uint size)
bool	play (QPainter *)
bool	load (QIODevice *dev, const char *format=0)
bool	load (const QString &fileName, const char *format=0)
bool	save (QIODevice *dev, const char *format=0)
bool	save (const QString &fileName, const char *format=0)
QRect	boundingRect () const
void	setBoundingRect (const QRect &r)
QPicture &	operator= (const QPicture &)
	QPicture (int formatVersion=-1)
	QPicture (const QPicture &)
	~QPicture ()
bool	isNull () const
uint	size () const
const char *	data () const
virtual void	setData (const char *data, uint size)
bool	play (QPainter *)
bool	load (QIODevice *dev, const char *format=0)
bool	load (const QString &fileName, const char *format=0)
bool	save (QIODevice *dev, const char *format=0)
bool	save (const QString &fileName, const char *format=0)
QRect	boundingRect () const
void	setBoundingRect (const QRect &r)
QPicture &	operator= (const QPicture &)
Métodos protegidos
bool	cmd (int, QPainter *, QPDevCmdParam *)
int	metric (int) const
void	detach ()
QPicture	copy () const
bool	cmd (int, QPainter *, QPDevCmdParam *)
int	metric (int) const
void	detach ()
QPicture	copy () const
Amigas
Q_EXPORT QDataStream &	operator<< (QDataStream &, const QPicture &)
Q_EXPORT QDataStream &	operator>> (QDataStream &, QPicture &)
Q_EXPORT QDataStream &	operator<< (QDataStream &, const QPicture &)
Q_EXPORT QDataStream &	operator>> (QDataStream &, QPicture &)

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Descripción detallada

The QPicture class is a paint device that records and replays QPainter commands.

A picture serializes painter commands to an IO device in a platform-independent format. For example, a picture created under Windows can be read on a Sun SPARC.

Pictures are called meta-files on some platforms.

Qt pictures use a proprietary binary format. Unlike native picture (meta-file) formats on many window systems, Qt pictures have no limitations regarding their contents. Everything that can be painted can also be stored in a picture, e.g. fonts, pixmaps, regions, transformed graphics, etc.

QPicture is an implicitly shared class.

Example of how to record a picture:

    QPicture  pic;
    QPainter  p;
    p.begin( &pic );               // paint in picture
    p.drawEllipse( 10,20, 80,70 ); // draw an ellipse
    p.end();                       // painting done
    pic.save( "drawing.pic" );     // save picture

Example of how to replay a picture:

    QPicture  pic;
    pic.load( "drawing.pic" );     // load picture
    QPainter  p;
    p.begin( &myWidget );          // paint in myWidget
    p.drawPicture( pic );          // draw the picture
    p.end();                       // painting done

Pictures can also be drawn using play(). Some basic data about a picture is available, for example, size(), isNull() and boundingRect().

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Documentación del constructor y destructor

QPicture::QPicture

(

int

formatVersion = -1

)

Constructs an empty picture.

The formatVersion parameter may be used to create a QPicture that can be read by applications that are compiled with earlier versions of Qt. formatVersion == 1 is binary compatible with Qt 1.x and later. formatVersion == 2 is binary compatible with Qt 2.0.x and later. formatVersion == 3 is binary compatible with Qt 2.1.x and later. formatVersion == 4 is binary compatible with Qt 3.0.x and later. formatVersion == 5 is binary compatible with Qt 3.1.

Note that the default formatVersion is -1 which signifies the current release, i.e. for Qt 3.1 a formatVersion of 5 is the same as the default formatVersion of -1.

Reading pictures generated by earlier versions of Qt is supported and needs no special coding; the format is automatically detected.

QPicture::QPicture

(

const QPicture &

pic

)

Constructs a shallow copy of pic.

QPicture::~QPicture

(

)

Destroys the picture.

QPicture::QPicture

(

int

formatVersion = -1

)

QPicture::QPicture

(

const QPicture &

)

QPicture::~QPicture

(

)

---

Documentación de las funciones miembro

QRect QPicture::boundingRect

(

)

const

Returns the picture's bounding rectangle or an invalid rectangle if the picture contains no data.

QRect QPicture::boundingRect

(

)

const

bool QPicture::cmd	(	int	,
		QPainter *	,
		QPDevCmdParam *
	)		[protected, virtual]

Internal virtual function that interprets drawing commands from the painter.

Implemented by subclasses that have no direct support for drawing graphics (external paint devices, for example QPicture).

Internal virtual function that interprets drawing commands from the painter.

Implemented by subclasses that have no direct support for drawing graphics (external paint devices, for example, QPicture).

Reimplementado de QPaintDevice.

bool QPicture::cmd	(	int	,
		QPainter *	,
		QPDevCmdParam *
	)		[protected, virtual]

Internal virtual function that interprets drawing commands from the painter.

Implemented by subclasses that have no direct support for drawing graphics (external paint devices, for example QPicture).

Internal virtual function that interprets drawing commands from the painter.

Implemented by subclasses that have no direct support for drawing graphics (external paint devices, for example, QPicture).

Reimplementado de QPaintDevice.

QPicture QPicture::copy

(

)

const [protected]

Returns a deep copy of the picture.

QPicture QPicture::copy

(

)

const [protected]

const char * QPicture::data

(

)

const [inline]

Returns a pointer to the picture data. The pointer is only valid until the next non-const function is called on this picture. The returned pointer is 0 if the picture contains no data.

Ver también:

size(), isNull()

const char* QPicture::data

(

)

const

void QPicture::detach

(

)

[protected]

Detaches from shared picture data and makes sure that this picture is the only one referring to the data.

If multiple pictures share common data, this picture makes a copy of the data and detaches itself from the sharing mechanism. Nothing is done if there is just a single reference.

void QPicture::detach

(

)

[protected]

bool QPicture::isNull

(

)

const

bool QPicture::isNull

(

)

const [inline]

Returns TRUE if the picture contains no data; otherwise returns FALSE.

bool QPicture::load	(	QIODevice *	dev,
		const char *	format = 0
	)

bool QPicture::load	(	const QString &	fileName,
		const char *	format = 0
	)

bool QPicture::load	(	QIODevice *	dev,
		const char *	format = 0
	)

Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. dev is the device to use for loading.

bool QPicture::load	(	const QString &	fileName,
		const char *	format = 0
	)

Loads a picture from the file specified by fileName and returns TRUE if successful; otherwise returns FALSE.

By default, the file will be interpreted as being in the native QPicture format. Specifying the format string is optional and is only needed for importing picture data stored in a different format.

Currently, the only external format supported is the W3C SVG format which requires the Qt XML module . The corresponding format string is "svg".

Ver también:

save()

int QPicture::metric

(

int

m

)

const [protected, virtual]

Internal implementation of the virtual QPaintDevice::metric() function.

Use the QPaintDeviceMetrics class instead.

A picture has the following hard-coded values: dpi=72, numcolors=16777216 and depth=24.

m is the metric to get.

Reimplementado de QPaintDevice.

int QPicture::metric

(

int

)

const [protected, virtual]

Internal virtual function that returns paint device metrics.

Please use the QPaintDeviceMetrics class instead.

Reimplementado de QPaintDevice.

QPicture& QPicture::operator=

(

const QPicture &

)

QPicture & QPicture::operator=

(

const QPicture &

p

)

Assigns a shallow copy of p to this picture and returns a reference to this picture.

bool QPicture::play

(

QPainter *

)

bool QPicture::play

(

QPainter *

painter

)

Replays the picture using painter, and returns TRUE if successful; otherwise returns FALSE.

This function does exactly the same as QPainter::drawPicture() with (x, y) = (0, 0).

bool QPicture::save	(	QIODevice *	dev,
		const char *	format = 0
	)

Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. dev is the device to use for saving.

bool QPicture::save	(	const QString &	fileName,
		const char *	format = 0
	)

Saves a picture to the file specified by fileName and returns TRUE if successful; otherwise returns FALSE.

Specifying the file format string is optional. It's not recommended unless you intend to export the picture data for use by a third party reader. By default the data will be saved in the native QPicture file format.

Currently, the only external format supported is the W3C SVG format which requires the Qt XML module . The corresponding format string is "svg".

Ver también:

load()

bool QPicture::save	(	QIODevice *	dev,
		const char *	format = 0
	)

bool QPicture::save	(	const QString &	fileName,
		const char *	format = 0
	)

void QPicture::setBoundingRect

(

const QRect &

r

)

void QPicture::setBoundingRect

(

const QRect &

r

)

Sets the picture's bounding rectangle to r. The automatically calculated value is overriden.

void QPicture::setData	(	const char *	data,
		uint	size
	)		[virtual]

Sets the picture data directly from data and size. This function copies the input data.

Ver también:

data(), size()

virtual void QPicture::setData	(	const char *	data,
		uint	size
	)		[virtual]

uint QPicture::size

(

)

const [inline]

Returns the size of the picture data.

Ver también:

data()

uint QPicture::size

(

)

const

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Documentación de las funciones relacionadas y clases amigas

QDataStream & operator<<	(	QDataStream &	s,
		const QPicture &	r
	)		[friend]

Writes picture r to the stream s and returns a reference to the stream.

Q_EXPORT QDataStream& operator<<	(	QDataStream &	,
		const QPicture &
	)		[friend]

Q_EXPORT QDataStream& operator>>	(	QDataStream &	,
		QPicture &
	)		[friend]

QDataStream & operator>>	(	QDataStream &	s,
		QPicture &	r
	)		[friend]

Reads a picture from the stream s into picture r and returns a reference to the stream.

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La documentación para esta clase fue generada a partir de los siguientes ficheros:

• src/qt/include/qpicture.h
• src/qt/src/kernel/qpicture.h
• src/qt/src/kernel/qpicture.cpp