QPicture Class Reference
^{^{[

QtGui

module]}}

QPicture 类是描绘设备，用于记录和重演 QPainter 命令。更多...

方法

__init__ ( self , int formatVersion = -1)
__init__ ( self , QPicture)
QRect boundingRect ( self )
str data ( self )
detach ( self )
int devType ( self )
bool isDetached ( self )
bool isNull ( self )
bool load ( self , QIODevice dev , str format = None)
bool load ( self , QString fileName , str format = None)
int metric ( self , QPaintDevice.PaintDeviceMetric m )
QPaintEngine paintEngine ( self )
bool play ( self , QPainter p )
bool save ( self , QIODevice dev , str format = None)
bool save ( self , QString fileName , str format = None)
setBoundingRect ( self , QRect r )
setData ( self , str data )
int size ( self )
swap ( self , QPicture other )

Static Methods

QStringList inputFormatList ()
list-of-QByteArray inputFormats ()
QStringList outputFormatList ()
list-of-QByteArray outputFormats ()
str pictureFormat (QString fileName )

详细描述

QPicture 类是描绘设备，用于记录和重演 QPainter 命令。

A picture serializes painter commands to an IO device in a platform-independent format. They are sometimes referred to as meta-files.

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 on a widget or pixmap (e.g., fonts, pixmaps, regions, transformed graphics, etc.) can also be stored in a picture.

QPicture is resolution independent, i.e. a QPicture can be displayed on different devices (for example svg, pdf, ps, printer and screen) looking the same. This is, for instance, needed for WYSIWYG print preview. QPicture runs in the default system dpi, and scales the painter to match differences in resolution depending on the window system.

Example of how to record a picture:

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

Note that the list of painter commands is reset on each call to the QPainter.begin () 函数。

Example of how to replay a picture:

         QPicture picture;
         picture.load("drawing.pic");           // load picture
         QPainter painter;
         painter.begin(&myImage);               // paint in myImage
         painter.drawPicture(0, 0, picture);    // draw the picture at (0,0)
         painter.end();                         // painting done

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

方法文档编制

QPicture.init ( self , int formatVersion = -1)

Constructs an empty picture.

formatVersion parameter may be used to create a QPicture that can be read by applications that are compiled with earlier versions of Qt.

Note that the default formatVersion is -1 which signifies the current release, i.e. for Qt 4.0 a formatVersion of 7 is the same as the default formatVersion of -1.

Reading pictures generated by earlier versions of Qt is not supported in Qt 4.0.

QPicture.init ( self , QPicture )

构造副本为 pic .

This constructor is fast thanks to 隐式共享 .

QRect QPicture.boundingRect ( self )

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

另请参阅 setBoundingRect ().

str QPicture.data ( self )

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.

另请参阅 setData (), size ()，和 isNull ().

QPicture.detach ( self )

int QPicture.devType ( self )

QStringList QPicture.inputFormatList ()

list-of-QByteArray QPicture.inputFormats ()

bool QPicture.isDetached ( self )

bool QPicture.isNull ( self )

Returns true if the picture contains no data; otherwise returns false.

bool QPicture.load ( self , QIODevice dev , str format = None)

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

Please note that the format parameter has been deprecated and will have no effect.

另请参阅 save ().

bool QPicture.load ( self , QString fileName , str format = None)

这是重载函数。

dev is the device to use for loading.

int QPicture.metric ( self , QPaintDevice.PaintDeviceMetric m )

QStringList QPicture.outputFormatList ()

list-of-QByteArray QPicture.outputFormats ()

QPaintEngine QPicture.paintEngine ( self )

str QPicture.pictureFormat (QString fileName )

bool QPicture.play ( self , QPainter p )

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 ( self , QIODevice dev , str format = None)

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

Please note that the format parameter has been deprecated and will have no effect.

另请参阅 load ().

bool QPicture.save ( self , QString fileName , str format = None)

这是重载函数。

dev is the device to use for saving.

QPicture.setBoundingRect ( self , QRect r )

Sets the picture's bounding rectangle to r 。 automatically calculated value is overridden.

另请参阅 boundingRect ().

QPicture.setData ( self , str data )

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

另请参阅 data () 和 size ().

int QPicture.size ( self )

Returns the size of the picture data.

另请参阅 data ().

QPicture.swap ( self , QPicture other )

Swaps picture other with this picture. This operation is very fast and never fails.

该函数在 Qt 4.8 引入。

QPicture Class Reference [ QtGui module]

方法