QBoxLayout(3qt)QBoxLayout(3qt)NAME
QBoxLayout - Lines up child widgets horizontally or
vertically
#include <qlayout.h>
Inherits QLayout.
Inherited by QHBoxLayout and QVBoxLayout.
Public Members
enum Direction { LeftToRight, RightToLeft, TopToBottom,
BottomToTop, Down = TopToBottom, Up = BottomToTop }
QBoxLayout ( QWidget * parent, Direction, int border=0,
int space = -1, const char * name=0 )
QBoxLayout ( QLayout * parentLayout, Direction, int space
= -1, const char * name=0 )
QBoxLayout ( Direction, int space = -1, const char *
name=0 )
~QBoxLayout ()
virtual void addItem ( QLayoutItem * )
Direction direction () const
void setDirection ( Direction )
void addSpacing ( int size )
void addStretch ( int stretch = 0 )
void addWidget ( QWidget *, int stretch = 0, int alignment
= 0 )
void addLayout ( QLayout * layout, int stretch = 0 )
void addStrut ( int )
void insertSpacing ( int index, int size )
void insertStretch ( int index, int stretch = 0 )
void insertWidget ( int index, QWidget * widget, int
stretch = 0, int alignment = 0 )
void insertLayout ( int index, QLayout * layout, int
stretch = 0 )
bool setStretchFactor ( QWidget *, int stretch )
bool setStretchFactor ( QLayout * l, int stretch )
virtual QSize sizeHint () const
virtual QSize minimumSize () const
virtual QSize maximumSize () const
virtual bool hasHeightForWidth () const
virtual int heightForWidth ( int ) const
virtual QSizePolicy::ExpandData expanding () const
virtual void invalidate ()
virtual void setGeometry ( const QRect & )
int findWidget ( QWidget * w )
Protected Members
void insertItem ( int index, QLayoutItem * )
DESCRIPTION
The QBoxLayout class lines up child widgets horizontally
or vertically.
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QBoxLayout(3qt)QBoxLayout(3qt)
QBoxLayout takes the space it gets (from its parent layout
or from the mainWidget()), divides it up into a row of
boxes and makes each managed widget fill one box.
If the QBoxLayout is Horizontal, the boxes are beside each
other, with suitable sizes. Each widget (or other box)
will get at least its minimum sizes and at most its
maximum size, and any excess space is shared according to
the stretch factors (more about that below).
If the QBoxLayout is Vertical, the boxes are above and
below each other, again with suitable sizes.
The easiest way to create a QBoxLayout is to use one of
the convenience classes QHBoxLayout (for Horizontal boxes)
or QVBoxLayout (for Vertical boxes). You can also use the
QBoxLayout constructor directly, specifying its direction
as LeftToRight, Down, RightToLeft or Up.
If the QBoxLayout is not the top-level layout (ie. is not
managing all of the widget's area and children), you must
add it to its parent layout before you can do anything
with it. The normal way to add a layout is by calling
parentLayout->addLayout().
Once you have done that, you can add boxes to the
QBoxLayout using one of four functions:
addWidget() to add a widget to the QBoxLayout and set the
widget's stretch factor. (The stretch factor is along the
row of boxes.)
addSpacing() to create an empty box; this is one of the
functions you use to create nice and spacious dialogs. See
below for ways to set margins.
addStretch() to create an empty, stretchable box.
addLayout() to add a box containing another QLayout to the
row and set that layout's stretch factor.
Use insertWidget(), insertSpacing(), insertStretch() or
insertLayout() to insert a box at a specified position in
the layout.
QBoxLayout also includes two margin widths:
setMargin() sets the width of the outer border. This is
the width of the reserved space along each of the
QBoxLayout's four sides.
setSpacing() sets the inter-box width. This is the width
of the automatically allocated spacing between
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neighbouring boxes. (You can use addSpacing() to get more
space at a .)
The outer border width defaults to 0, and the intra-widget
width defaults to the same as the border width for a top-
level layout, or to the same as the parent layout
otherwise. Both can be set using arguments to the
constructor.
You will almost always want to use the convenience classes
for QBoxLayout: QVBoxLayout and QHBoxLayout, because of
their simpler constructors.
See also the Layout overview documentation
Examples: layout/layout.cpp popup/popup.cpp
customlayout/main.cpp
Member Type Documentation
QBoxLayout::Direction
This type is used to determine the direction of a box
layout. The possible values are:
LeftToRight - Horizontal, from left to right
RightToLeft - Horizontal, from right to left
TopToBottom - Vertical, from top to bottom
Down - An alias for TopToBottom
BottomToTop - Vertical, from bottom to top
Up - An alias for BottomToTop
MEMBER FUNCTION DOCUMENTATIONQBoxLayout::QBoxLayout ( Direction d, int space = -1, const char
* name=0 )
If space is -1, this QBoxLayout will inherit its parent's
spacing(), otherwise space is used.
You have to insert this box into another layout.
Examples: layout/layout.cpp
QBoxLayout::QBoxLayout ( QLayout * parentLayout, Direction d, int
space = -1, const char * name=0 )
Constructs a new QBoxLayout with direction d and inserts
it into parentLayout.
QBoxLayout::QBoxLayout ( QWidget * parent, Direction d, int
border=0, int space = -1, const char * name=0 )
Constructs a new QBoxLayout with direction d and main
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QBoxLayout(3qt)QBoxLayout(3qt)
widget parent. parent may not be 0.
border is the number of pixels between the edge of the
widget and the managed children. space is the default
number of pixels between neighbouring children. If space
is -1 the value of border is used.
name is the internal object name
See also direction().
QBoxLayout::~QBoxLayout ()
Destructs this box.
void QBoxLayout::addItem ( QLayoutItem * item ) [virtual]
Adds item to the end of this box layout.
Reimplemented from QLayout.
void QBoxLayout::addLayout ( QLayout * layout, int stretch = 0 )
Adds layout to the end of the box, with serial stretch
factor stretch.
See also insertLayout(), setAutoAdd(), addWidget() and
addSpacing().
void QBoxLayout::addSpacing ( int size )
Adds a non-stretchable space with size size to the end of
this box layout. QBoxLayout gives default border and
spacing. This function adds additional space.
See also insertSpacing() and addStretch().
void QBoxLayout::addStretch ( int stretch = 0 )
Adds a stretchable space with zero minimum size and
stretch factor stretch to the end of this box layout.
See also addSpacing().
void QBoxLayout::addStrut ( int size )
Limits the perpendicular dimension of the box (e.g. height
if the box is LeftToRight) to a minimum of size. Other
constraints may increase the limit.
void QBoxLayout::addWidget ( QWidget * widget, int stretch = 0,
int alignment = 0 )
Adds widget to the end of this box layout, with a stretch
factor stretch and alignment alignment.
The stretch factor applies only in the direction of the
QBoxLayout, and is relative to the other boxes and widgets
in this QBoxLayout. Widgets and boxes with higher stretch
factor grow more.
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If the stretch factor is 0 and nothing else in the
QBoxLayout has a stretch factor greater than zero, the
space is distributed according to the QWidget:sizePolicy()
of each widget that's involved.
Alignment is specified by alignment which is a bitwise OR
of Qt::AlignmentFlags values. The default alignment is 0,
which means that the widget fills the entire cell.
Note: The alignment parameter is interpreted more
aggressively than in previous versions of Qt. A non-
default alignment now indicates that the widget should not
grow to fill the available space, but should be sized
according to sizeHint().
See also insertWidget(), setAutoAdd(), addLayout() and
addSpacing().
Examples: layout/layout.cpp popup/popup.cpp
scrollview/scrollview.cpp customlayout/main.cpp
QBoxLayout::Direction QBoxLayout::direction() const
Returns the (serial) direction of the box. addWidget() and
addSpacing() work in this direction; the stretch stretches
in this direction.
The directions are LeftToRight, RightToLeft, TopToBottom
and BottomToTop. For the last two, the shorter aliases
Down and Up are also available.
See also addWidget() and addSpacing().
QSizePolicy::ExpandData QBoxLayout::expanding() const [virtual]
Returns the expansiveness of this layout.
Reimplemented from QLayoutItem.
int QBoxLayout::findWidget ( QWidget * w )
Searches for w in this layout (not including child
layouts).
Returns the index of w, or -1 if w is not found.
bool QBoxLayout::hasHeightForWidth () const [virtual]
Returns whether this layout's preferred height depends on
its width.
Reimplemented from QLayoutItem.
int QBoxLayout::heightForWidth ( int w ) const [virtual]
Returns the layout's preferred height when it is w pixels
wide.
Reimplemented from QLayoutItem.
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QBoxLayout(3qt)QBoxLayout(3qt)void QBoxLayout::insertItem ( int index, QLayoutItem * item )
[protected]
Inserts item in this box layout at index index. If index
is negative, the item is added at the end.
Warning: does not call QLayout::insertChildLayout() if
item is a QLayout.
See also addItem() and findWidget().
void QBoxLayout::insertLayout ( int index, QLayout * layout, int
stretch = 0 )
Inserts layout at index index, with serial stretch factor
stretch. If index is negative, the layout is added at the
end.
See also setAutoAdd(), insertWidget() and insertSpacing().
void QBoxLayout::insertSpacing ( int index, int size )
Inserts a non-stretchable space at index index with size
size. If index is negative, the space is added at the end.
QBoxLayout gives default border and spacing. This function
adds additional space.
See also insertStretch().
void QBoxLayout::insertStretch ( int index, int stretch = 0 )
Inserts a stretchable space at index index with zero
minimum size and stretch factor stretch. If index is
negative, the space is added at the end.
See also insertSpacing().
void QBoxLayout::insertWidget ( int index, QWidget * widget, int
stretch = 0, int alignment = 0 )
Inserts widget at index index, with a stretch factor and
alignment. If index is negative, the widget is added at
the end.
The stretch factor applies only in the direction of the
QBoxLayout, and is relative to the other boxes and widgets
in this QBoxLayout. Widgets and boxes with higher stretch
factor grow more.
If the stretch factor is 0 and nothing else in the
QBoxLayout has a stretch factor greater than zero, the
space is distributed according to the QWidget:sizePolicy()
of each widget that's involved.
Alignment is specified by alignment which is a bitwise OR
of Qt::AlignmentFlags values. The default alignment is 0,
which means that the widget fills the entire cell.
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Note: The alignment parameter is interpreted more
aggressively than in previous versions of Qt. A non-
default alignment now indicates that the widget should not
grow to fill the available space, but should be sized
according to sizeHint().
See also setAutoAdd(), insertLayout() and insertSpacing().
void QBoxLayout::invalidate () [virtual]
Resets cached information.
Reimplemented from QLayoutItem.
QLayoutIterator QBoxLayout::iterator () [virtual]
Reimplemented for internal reasons; the API is not
affected.
Reimplemented from QLayoutItem.
QSize QBoxLayout::maximumSize () const [virtual]
Returns the maximum size needed by this box.
Reimplemented from QLayoutItem.
QSize QBoxLayout::minimumSize () const [virtual]
Returns the minimum size needed by this box.
Reimplemented from QLayoutItem.
void QBoxLayout::setDirection ( Direction direction )
Sets the direction of this layout to direction.
void QBoxLayout::setGeometry ( const QRect & r ) [virtual]
Resizes managed widgets within the rectangle r.
Reimplemented from QLayoutItem.
bool QBoxLayout::setStretchFactor ( QLayout * l, int stretch )
Sets the stretch factor for the layout l to stretch and
returns TRUE, if l is found in this layout (not including
child layouts).
Returns FALSE if l is not found.
bool QBoxLayout::setStretchFactor ( QWidget * w, int stretch )
Sets the stretch factor for widget w to stretch and
returns TRUE, if w is found in this layout (not including
child layouts).
Returns FALSE if w is not found.
QSize QBoxLayout::sizeHint () const [virtual]
Returns the preferred size of this grid.
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Reimplemented from QLayoutItem.
SEE ALSO
http://doc.trolltech.com/qboxlayout.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.
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Please include the name of the manual page
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