QSizePolicy(3qt)QSizePolicy(3qt)NAMEQSizePolicy - A layout attribute describing horizontal and
vertical resizing
#include <qsizepolicy.h>
Public Members
enum SizeType { Fixed = 0, Minimum = MayGrow, Maximum =
MayShrink, Preferred = MayGrow|MayShrink,
MinimumExpanding = Minimum|ExpMask, Expanding =
MinimumExpanding|MayShrink }
enum ExpandData { NoDirection = 0, Horizontal = 1,
Vertical = 2, BothDirections = Horizontal | Vertical }
QSizePolicy ()
QSizePolicy ( SizeType hor, SizeType ver, bool hfw = FALSE
)
SizeType horData () const
SizeType verData () const
bool mayShrinkHorizontally () const
bool mayShrinkVertically () const
bool mayGrowHorizontally () const
bool mayGrowVertically () const
ExpandData expanding () const
void setHorData ( SizeType d )
void setVerData ( SizeType d )
void setHeightForWidth ( bool b )
bool hasHeightForWidth () const
bool operator== ( const QSizePolicy & s ) const
bool operator!= ( const QSizePolicy & s ) const
DESCRIPTION
A layout attribute describing horizontal and vertical
resizing.
The size policy of a widget is an expression of its
willingness to be resized in various ways.
Widgets which reimplement QWidget::sizePolicy() return a
QSizePolicy describing the horizontal and vertical
resizing policy best used when laying out the widget. Only
one of the constructors is of interest in most
applications.
QSizePolicy contains two independent SizeType objects, one
which describes the widgets's horizontal size policy and
one which describes its vertical size policy, and it
contains a flag to indicate whether the height and width
of its preferred size are related.
The per-dimension SizeType objects are set in the usual
constructor, and can be queried using a variety of
functions, none of which are really interesting to
application programmers.
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QSizePolicy(3qt)QSizePolicy(3qt)
The hasHeightForWidth() flag indicates whether the
widget's sizeHint() is width-dependent (like a word-
wrapping label).
See also QSizePolicy::SizeType.
Examples: xform/xform.cpp
Member Type Documentation
QSizePolicy::ExpandData
This enum type describes in which directions a widget can
make use of extra space. There are four possible values:
NoDirection - the widget cannot make us of extra space in
any direction.
Horizontal - the widget can usefully be wider than
sizeHint() says.
Vertical - the widget can usefully be taller than
sizeHint() says.
BothDirections - the widget can usefully be both wider and
taller than sizeHint() says.
QSizePolicy::SizeType
The per-dimension sizing types used when constructing a
QSizePolicy are:
Fixed - the sizeHint() is the only acceptable alternative,
so widget can never grow or shrink (eg. the vertical
direction of a pushbutton).
Minimum - the sizeHint() is minimal, and sufficient. The
widget can be expanded, but there is no advantage to it
being larger (eg. the horizontal direction of a
pushbutton).
Maximum - the sizeHint() is a maximum. The widget can be
shrunk any amount without detriment if other widgets need
the space (eg. a separator line).
Preferred - the sizeHint() is best, but the widget can be
shrunk below that and still be useful. The widget can be
expanded, but there is no advantage to it being larger
than sizeHint() (the default QWidget policy).
MinimumExpanding - the sizeHint() is a minimum. The widget
can make use of extra space, so it should get as much
space as possible (not currently used by any standard Qt
widgets).
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QSizePolicy(3qt)QSizePolicy(3qt)
Expanding - the sizeHint() is a sensible size, but the
widget can be shrunk below that and still be useful. The
widget can make use of extra space, so it should get as
much space as possible (eg. the horizontal direction of a
slider).
MEMBER FUNCTION DOCUMENTATIONQSizePolicy::QSizePolicy ()
Default constructor, produces a minimally initialized
QSizePolicy.
QSizePolicy::QSizePolicy ( SizeType hor, SizeType ver, bool hfw =
FALSE )
This is the constructor normally used to return a value in
the overridden QWidget::sizePolicy() function of a QWidget
subclass.
It constructs a QSizePolicy with independent horizontal
and vertical sizing types, hor and ver respectively. These
sizing types affect how the widget is treated by the
layout engine.
If hfw is TRUE, the preferred height of the widget is
dependent on the width of the widget (for example, a
QLabel with automatic word-breaking).
QSizePolicy::ExpandData QSizePolicy::expanding() const
Returns a value indicating if the widget can make use of
extra space (ie. if it "wants" to grow) horizontally
and/or vertically.
bool QSizePolicy::hasHeightForWidth () const
Returns TRUE if the widget's preferred height depends on
its width.
QSizePolicy::SizeType QSizePolicy::horData() const
Returns the horizontal component of the size policy.
bool QSizePolicy::mayGrowHorizontally () const
Returns TRUE if the widget can sensibly be wider than its
sizeHint().
bool QSizePolicy::mayGrowVertically () const
Returns TRUE if the widget can sensibly be taller than its
sizeHint().
bool QSizePolicy::mayShrinkHorizontally () const
Returns TRUE if the widget can sensibly be narrower than
its sizeHint().
bool QSizePolicy::mayShrinkVertically () const
Returns TRUE if the widget can sensibly be lower than its
sizeHint().
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QSizePolicy(3qt)QSizePolicy(3qt)void QSizePolicy::setHeightForWidth ( bool b )
Sets the hasHeightForWidth() flag to b.
void QSizePolicy::setHorData ( SizeType d )
Sets the horizontal component of the size policy to d.
void QSizePolicy::setVerData ( SizeType d )
Sets the vertical component of the size policy to d.
QSizePolicy::SizeType QSizePolicy::verData() const
Returns the vertical component of the size policy.
SEE ALSO
http://doc.trolltech.com/qsizepolicy.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
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make our job much simpler. Thank you.
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manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page
(qsizepolicy.3qt) and the Qt version (2.3.1).
Trolltech AS 13 June 2001 4
