QPen(3qt)QPen(3qt)NAME
QPen - Defines how a
#include <qpen.h>
Inherits Qt.
Public Members
QPen ()
QPen ( PenStyle )
QPen ( const QColor & color, uint width=0, PenStyle
style=SolidLine )
QPen ( const QColor & cl, uint w, PenStyle s, PenCapStyle
c, PenJoinStyle j )
QPen ( const QPen & )
~QPen ()
QPen& operator= ( const QPen & )
PenStyle style () const
void setStyle ( PenStyle )
uint width () const
void setWidth ( uint )
const QColor& color () const
void setColor ( const QColor & )
PenCapStyle capStyle () const
void setCapStyle ( PenCapStyle )
PenJoinStyle joinStyle () const
void setJoinStyle ( PenJoinStyle )
bool operator== ( const QPen & p ) const
bool operator!= ( const QPen & p ) const
RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
QDataStream & operator<< (QDataStream & s, const QPen & p)
QDataStream & operator>> (QDataStream & s, QPen & p)
DESCRIPTION
The QPen class defines how a QPainter should draw lines
and outlines of shapes.
A pen has a style, a width, a color, a cap style and a
join style.
The pen style defines the line type. The default pen style
is Qt::SolidLine. Setting the style to NoPen tells the
painter to not draw lines or outlines.
The pen width defines the line width. The default line
width is 0, which draws a 1-pixel line very fast, but with
lower precision than with a line width of 1. Setting the
line width to 1 or more draws lines that are precise, but
drawing is slower.
The pen color defines the color of lines and text. The
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default line color is black. The QColor documentation
lists predefined colors.
The cap style defines how the end points of lines are
drawn. The join style defines how the joins between two
lines drawn when multiple, connected lines are drawn
(QPainter::drawPolyLine() etc.). The cap and join styles
apply only to wide lines, i.e. when the width is 1 or
greater.
Use the QBrush class for specifying fill styles.
Example:
QPainter painter;
QPen pen( red, 2 ); // red solid line, 2 pixel width
painter.begin( &anyPaintDevice ); // paint something
painter.setPen( pen ); // set the red, fat pen
painter.drawRect( 40,30, 200,100 ); // draw rectangle
painter.setPen( blue ); // set blue pen, 0 pixel width
painter.drawLine( 40,30, 240,130 ); // draw diagonal in rectangle
painter.end(); // painting done
See the setStyle() function for a complete list of pen
styles.
About the end point of lines: For wide (non-0-width) pens,
it depends on the cap style whether the end point is drawn
or not. For 0-width pens, QPainter will try to make sure
that the end point is drawn, but this cannot be absolutely
guaranteed, since the underlying drawing engine is free to
use any (typically accellerated) algorithm for drawing
0-width lines. On all tested systems, however, the
endpoint of at least all non-diagonal lines are drawn.
See also QPainter and QPainter::setPen().
Examples: progress/progress.cpp desktop/desktop.cpp
MEMBER FUNCTION DOCUMENTATIONQPen::QPen ()
Constructs a default black solid line pen with 0 width.
QPen::QPen ( PenStyle style )
Constructs a pen black with 0 width and a specified style.
See also setStyle().
QPen::QPen ( const QColor & cl, uint w, PenStyle s, PenCapStyle
c, PenJoinStyle j )
Constructs a pen with a specified color, width and styles.
See also setWidth(), setStyle() and setColor().
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QPen(3qt)QPen(3qt)QPen::QPen ( const QColor & color, uint width=0, PenStyle
style=SolidLine )
Constructs a pen with a specified color, width and style.
See also setWidth(), setStyle() and setColor().
QPen::QPen ( const QPen & p )
Constructs a pen which is a copy of p.
QPen::~QPen ()
Destructs the pen.
Qt::PenCapStyle QPen::capStyle() const
Returns the pen's cap style.
See also setCapStyle().
const QColor & QPen::color () const
Returns the pen color.
See also setColor().
Qt::PenJoinStyle QPen::joinStyle() const
Returns the pen's join style.
See also setJoinStyle().
bool QPen::operator!= ( const QPen & p ) const
Returns TRUE if the pen is different from p, or FALSE if
the pens are equal.
Two pens are different if they have different styles,
widths or colors.
See also operator==().
QPen & QPen::operator= ( const QPen & p )
Assigns c to this pen and returns a reference to this pen.
bool QPen::operator== ( const QPen & p ) const
Returns TRUE if the pen is equal to p, or FALSE if the
pens are different.
Two pens are equal if they have equal styles, widths and
colors.
See also operator!=().
void QPen::setCapStyle ( PenCapStyle c )
Sets the pen's cap style to c.
The default value is FlatCap. The cap style has no effect
on 0-width pens.
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QPen(3qt)QPen(3qt)
Warning: On Windows 95/98, the cap style setting has no
effect. Wide lines are rendered as if the cap style was
SquareCap.
See also capStyle().
void QPen::setColor ( const QColor & c )
Sets the pen color to c.
See also color().
Examples: progress/progress.cpp
void QPen::setJoinStyle ( PenJoinStyle j )
Sets the pen's join style to j.
The default value is MiterJoin. The join style has no
effect on 0-width pens.
Warning: On Windows 95/98, the join style setting has no
effect. Wide lines are rendered as if the join style was
BevelJoin.
See also joinStyle().
void QPen::setStyle ( PenStyle s )
Sets the pen style to s.
Warning: On Windows 95/98, the style setting (other than
NoPen and SolidLine) has no effect for lines with width
greater than 1.
See also style().
void QPen::setWidth ( uint w )
Sets the pen width to w.
See also width().
Examples: progress/progress.cpp
PenStyle QPen::style () const
Returns the pen style.
See also setStyle().
uint QPen::width () const
Returns the pen width.
See also setWidth().
RELATED FUNCTION DOCUMENTATIONQDataStream & operator<;< (QDataStream & s, const QPen & p)
Writes a pen to the stream and returns a reference to the
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QPen(3qt)QPen(3qt)
stream.
See also Format of the QDataStream operators
QDataStream & operator>> (QDataStream & s, QPen & p)
Reads a pen from the stream and returns a reference to the
stream.
See also Format of the QDataStream operators
SEE ALSO
http://doc.trolltech.com/qpen.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
If you find a bug in Qt, please report it as described in
http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qpen.3qt) and
the Qt version (2.3.1).
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