QGridLayout(3qt)QGridLayout(3qt)NAME
QGridLayout - Lays out widgets in a grid
SYNOPSIS
#include <qlayout.h>
Inherits QLayout.
Public Members
QGridLayout ( QWidget * parent, int nRows = 1, int nCols = 1, int
margin = 0, int space = -1, const char * name = 0 )
QGridLayout ( int nRows = 1, int nCols = 1, int spacing = -1, const
char * name = 0 )
QGridLayout ( QLayout * parentLayout, int nRows = 1, int nCols = 1, int
spacing = -1, const char * name = 0 )
~QGridLayout ()
virtual QSize sizeHint () const
virtual QSize minimumSize () const
virtual QSize maximumSize () const
virtual void setRowStretch ( int row, int stretch )
virtual void setColStretch ( int col, int stretch )
int rowStretch ( int row ) const
int colStretch ( int col ) const
void setRowSpacing ( int row, int minSize )
void setColSpacing ( int col, int minSize )
int rowSpacing ( int row ) const
int colSpacing ( int col ) const
int numRows () const
int numCols () const
QRect cellGeometry ( int row, int col ) const
virtual bool hasHeightForWidth () const
virtual int heightForWidth ( int w ) const
virtual QSizePolicy::ExpandData expanding () const
virtual void invalidate ()
virtual void addItem ( QLayoutItem * item )
void addItem ( QLayoutItem * item, int row, int col )
void addMultiCell ( QLayoutItem * item, int fromRow, int toRow, int
fromCol, int toCol, int alignment = 0 )
void addWidget ( QWidget * w, int row, int col, int alignment = 0 )
void addMultiCellWidget ( QWidget * w, int fromRow, int toRow, int
fromCol, int toCol, int alignment = 0 )
void addLayout ( QLayout * layout, int row, int col )
void addMultiCellLayout ( QLayout * layout, int fromRow, int toRow, int
fromCol, int toCol, int alignment = 0 )
void addRowSpacing ( int row, int minsize ) (obsolete)
void addColSpacing ( int col, int minsize ) (obsolete)
void expand ( int nRows, int nCols )
enum Corner { TopLeft, TopRight, BottomLeft, BottomRight }
void setOrigin ( Corner c )
Corner origin () const
virtual void setGeometry ( const QRect & r )
Protected Members
bool findWidget ( QWidget * w, int * row, int * col )
void add ( QLayoutItem * item, int row, int col )
DESCRIPTION
The QGridLayout class lays out widgets in a grid.
QGridLayout takes the space made available to it (by its parent layout
or by the mainWidget()), divides it up into rows and columns, and puts
each widget it manages into the correct cell.
Columns and rows behave identically; we will discuss columns, but there
are equivalent functions for rows.
Each column has a minimum width and a stretch factor. The minimum width
is the greatest of that set using addColSpacing() and the minimum width
of each widget in that column. The stretch factor is set using
setColStretch() and determines how much of the available space the
column will get over and above its necessary minimum.
Normally, each managed widget or layout is put into a cell of its own
using addWidget(), addLayout() or by the auto-add facility. It is also
possible for a widget to occupy multiple cells using
addMultiCellWidget(). If you do this, QGridLayout will guess how to
distribute the size over the columns/rows (based on the stretch
factors).
To remove a widget from a layout, call remove(). Calling
QWidget::hide() on a widget also effectively removes the widget from
the layout until QWidget::show() is called.
This illustration shows a fragment of a dialog with a five-column,
three-row grid (the grid is shown overlaid in magenta):
<center>
[Image Omitted]
</center>
Columns 0, 2 and 4 in this dialog fragment are made up of a QLabel, a
QLineEdit, and a QListBox. Columns 1 and 3 are placeholders made with
addColSpacing(). Row 0 consists of three QLabel objects, row 1 of three
QLineEdit objects and row 2 of three QListBox objects. We used
placeholder columns (1 and 3) to get the right amount of space between
the columns.
Note that the columns and rows are not equally wide or tall. If you
want two columns to have the same width, you must set their minimum
widths and stretch factors to be the same yourself. You do this using
addColSpacing() and setColStretch().
If the QGridLayout is not the top-level layout (i.e. does not manage
all of the widget's area and children), you must add it to its parent
layout when you create it, but before you do anything with it. The
normal way to add a layout is by calling parentLayout->addLayout().
Once you have added your layout you can start putting widgets and other
layouts into the cells of your grid layout using addWidget(),
addLayout() and addMultiCellWidget().
QGridLayout also includes two margin widths: the border and the
spacing. The border is the width of the reserved space along each of
the QGridLayout's four sides. The spacing is the width of the
automatically allocated spacing between neighboring boxes.
Both the border and the spacing are parameters of the constructor and
default to 0.
See also QGrid, Layout Overview, Widget Appearance and Style, and
Layout Management.
Member Type Documentation
QGridLayout::Corner
This enum identifies which corner is the origin (0, 0) of the layout.
QGridLayout::TopLeft - the top-left corner
QGridLayout::TopRight - the top-right corner
QGridLayout::BottomLeft - the bottom-left corner
QGridLayout::BottomRight - the bottom-right corner
MEMBER FUNCTION DOCUMENTATIONQGridLayout::QGridLayout ( QWidget * parent, int nRows = 1, int nCols = 1, int
margin = 0, int space = -1, const char * name = 0 )
Constructs a new QGridLayout with nRows rows, nCols columns and parent
widget, parent. parent may not be 0. The grid layout is called name.
margin is the number of pixels between the edge of the widget and its
managed children. space is the default number of pixels between cells.
If space is -1, the value of margin is used.
QGridLayout::QGridLayout ( int nRows = 1, int nCols = 1, int spacing = -1,
const char * name = 0 )
Constructs a new grid with nRows rows and nCols columns. If spacing is
-1, this QGridLayout inherits its parent's spacing(); otherwise spacing
is used. The grid layout is called name.
You must insert this grid into another layout. You can insert widgets
and layouts into this layout at any time, but laying out will not be
performed before this is inserted into another layout.
QGridLayout::QGridLayout ( QLayout * parentLayout, int nRows = 1, int nCols =
1, int spacing = -1, const char * name = 0 )
Constructs a new grid that is placed inside parentLayout with nRows
rows and nCols columns. If spacing is -1, this QGridLayout inherits its
parent's spacing(); otherwise spacing is used. The grid layout is
called name.
This grid is placed according to parentLayout's default placement
rules.
QGridLayout::~QGridLayout ()
Destroys the grid layout. Geometry management is terminated if this is
a top-level grid.
The layout's widgets aren't destroyed.
void QGridLayout::add ( QLayoutItem * item, int row, int col ) [protected]
Adds item at position row, col. The layout takes ownership of the item.
void QGridLayout::addColSpacing ( int col, int minsize )
This function is obsolete. It is provided to keep old source working.
We strongly advise against using it in new code.
Sets the minimum width of column col to minsize pixels.
Use setColSpacing() instead.
void QGridLayout::addItem ( QLayoutItem * item, int row, int col )
Adds item at position row, col. The layout takes ownership of the item.
void QGridLayout::addItem ( QLayoutItem * item ) [virtual]
This is an overloaded member function, provided for convenience. It
behaves essentially like the above function.
Adds item to the next free position of this layout.
Reimplemented from QLayout.
void QGridLayout::addLayout ( QLayout * layout, int row, int col )
Places the layout at position (row, col) in the grid. The top-left
position is (0, 0).
layout becomes a child of the grid layout.
When a layout is constructed with another layout as its parent, you
don't need to call addLayout(); the child layout is automatically added
to the parent layout as it is constructed.
See also addMultiCellLayout().
Examples:
void QGridLayout::addMultiCell ( QLayoutItem * item, int fromRow, int toRow,
int fromCol, int toCol, int alignment = 0 )
Adds the item to the cell grid, spanning multiple rows/columns.
The cell will span from fromRow, fromCol to toRow, toCol. 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.
void QGridLayout::addMultiCellLayout ( QLayout * layout, int fromRow, int
toRow, int fromCol, int toCol, int alignment = 0 )
Adds the layout layout to the cell grid, spanning multiple
rows/columns. The cell will span from fromRow, fromCol to toRow, toCol.
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.
A non-zero alignment indicates that the layout should not grow to fill
the available space but should be sized according to sizeHint().
layout becomes a child of the grid layout.
See also addLayout().
void QGridLayout::addMultiCellWidget ( QWidget * w, int fromRow, int toRow,
int fromCol, int toCol, int alignment = 0 )
Adds the widget w to the cell grid, spanning multiple rows/columns. The
cell will span from fromRow, fromCol to toRow, toCol.
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.
A non-zero alignment indicates that the widget should not grow to fill
the available space but should be sized according to sizeHint().
See also addWidget().
Examples:
void QGridLayout::addRowSpacing ( int row, int minsize )
This function is obsolete. It is provided to keep old source working.
We strongly advise against using it in new code.
Sets the minimum height of row row to minsize pixels.
Use setRowSpacing() instead.
void QGridLayout::addWidget ( QWidget * w, int row, int col, int alignment = 0
)
Adds the widget w to the cell grid at row, col. The top-left position
is (0, 0) by default.
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.
You should not call this if you have enabled the auto-add facility of
the layout.
From Qt 3.0, 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 addMultiCellWidget().
Examples:
QRect QGridLayout::cellGeometry ( int row, int col ) const
Returns the geometry of the cell with row row and column col in the
grid. Returns an invalid rectangle if row or col is outside the grid.
Warning: in the current version of Qt this function does not return
valid results until setGeometry() has been called, i.e. after the
mainWidget() is visible.
int QGridLayout::colSpacing ( int col ) const
Returns the column spacing for column col.
See also setColSpacing().
int QGridLayout::colStretch ( int col ) const
Returns the stretch factor for column col.
See also setColStretch().
void QGridLayout::expand ( int nRows, int nCols )
Expands this grid so that it will have nRows rows and nCols columns.
Will not shrink the grid. You should not need to call this function
because QGridLayout expands automatically as new items are inserted.
QSizePolicy::ExpandData QGridLayout::expanding () const [virtual]
Returns whether this layout can make use of more space than sizeHint().
A value of Vertical or Horizontal means that it wants to grow in only
one dimension, whereas BothDirections means that it wants to grow in
both dimensions.
Reimplemented from QLayout.
bool QGridLayout::findWidget ( QWidget * w, int * row, int * col ) [protected]
Searches for widget w in this layout (not including child layouts). If
w is found, it sets <em>row</em> and <em>col</em> to the row and column
and returns TRUE; otherwise returns FALSE.
Note: if a widget spans multiple rows/columns, the top-left cell is
returned.
bool QGridLayout::hasHeightForWidth () const [virtual]
Returns TRUE if this layout's preferred height depends on its width;
otherwise returns FALSE.
Reimplemented from QLayoutItem.
int QGridLayout::heightForWidth ( int w ) const [virtual]
Returns the layout's preferred height when it is w pixels wide.
Reimplemented from QLayoutItem.
void QGridLayout::invalidate () [virtual]
Resets cached information.
Reimplemented from QLayout.
QSize QGridLayout::maximumSize () const [virtual]
Returns the maximum size needed by this grid.
Reimplemented from QLayout.
QSize QGridLayout::minimumSize () const [virtual]
Returns the minimum size needed by this grid.
Reimplemented from QLayout.
int QGridLayout::numCols () const
Returns the number of columns in this grid.
int QGridLayout::numRows () const
Returns the number of rows in this grid.
Corner QGridLayout::origin () const
Returns the corner that's used for the grid's origin, i.e. for position
(0, 0).
int QGridLayout::rowSpacing ( int row ) const
Returns the row spacing for row row.
See also setRowSpacing().
int QGridLayout::rowStretch ( int row ) const
Returns the stretch factor for row row.
See also setRowStretch().
void QGridLayout::setColSpacing ( int col, int minSize )
Sets the minimum width of column col to minSize pixels.
See also colSpacing() and setRowSpacing().
void QGridLayout::setColStretch ( int col, int stretch ) [virtual]
Sets the stretch factor of column col to stretch. The first column is
number 0.
The stretch factor is relative to the other columns in this grid.
Columns with a higher stretch factor take more of the available space.
The default stretch factor is 0. If the stretch factor is 0 and no
other column in this table can grow at all, the column may still grow.
See also colStretch(), addColSpacing(), and setRowStretch().
Examples:
void QGridLayout::setGeometry ( const QRect & r ) [virtual]
Resizes managed widgets within the rectangle r.
Reimplemented from QLayout.
void QGridLayout::setOrigin ( Corner c )
Sets the grid's origin corner, i.e. position (0, 0), to c.
void QGridLayout::setRowSpacing ( int row, int minSize )
Sets the minimum height of row row to minSize pixels.
See also rowSpacing() and setColSpacing().
void QGridLayout::setRowStretch ( int row, int stretch ) [virtual]
Sets the stretch factor of row row to stretch. The first row is number
0.
The stretch factor is relative to the other rows in this grid. Rows
with a higher stretch factor take more of the available space.
The default stretch factor is 0. If the stretch factor is 0 and no
other row in this table can grow at all, the row may still grow.
See also rowStretch(), setRowSpacing(), and setColStretch().
Examples:
QSize QGridLayout::sizeHint () const [virtual]
Returns the preferred size of this grid.
Reimplemented from QLayoutItem.
SEE ALSO
http://doc.trolltech.com/qgridlayout.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2007 Trolltech ASA, 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 help us to
help you. Thank you.
The definitive Qt documentation is provided in HTML format; it is
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If you find errors in this manual page, please report them to qt-
bugs@trolltech.com. Please include the name of the manual page
(qgridlayout.3qt) and the Qt version (3.3.8).
Trolltech AS 2 February 2007 QGridLayout(3qt)
