QTableView Class Reference
This is an abstract base class for implementing tables
More...
#include <qtableview.h>
Inherits QFrame.
Inherited by QMultiLineEdit.
List of all member functions.
Public Members
Protected Members
QTableView ( QWidget * parent=0, const char * name=0, WFlags f=0 )Â
-
-
-
-
-
-
-
-
-
-
-
-
-
-
virtual voidÂ
setOffset ( int x, int y, bool updateScrBars = TRUE )Â
-
-
-
-
-
-
-
-
-
-
-
-
-
-
voidÂ
updateCell ( int row, int column, bool erase=TRUE )Â
-
-
-
-
-
-
-
-
virtual voidÂ
paintCell ( QPainter *, int row, int col )Â
-
-
intÂ
findRow ( int yPos ) const
intÂ
findCol ( int xPos ) const
boolÂ
rowYPos ( int row, int * yPos ) const
boolÂ
colXPos ( int col, int * xPos ) const
-
-
-
-
-
-
-
-
-
-
voidÂ
scroll ( int xPixels, int yPixels )Â
-
-
Detailed Description
This is an abstract base class for implementing tables
A table view consists of a number of abstract cells organized in rows
and columns and a visible part called a view. The cells are identified
with a row index and a column index. The top left cell is in row 0,
column 0.
The behavior of the widget can be finely tuned using
setTableFlags(); a typical subclass will consist of little more than a
call to setTableFlags(), some table content manipulation, and an
implementation of paintCell(). Subclasses that need cells with
variable width or height must reimplement cellHeight() and/or
cellWidth(). Use updateTableSize() to tell QTableView when the
width or height has changed.
When you read this documentation, it is important to understand the
distinctions between the four pixel coordinate systems involved.
- The cell coordinates. (0,0) is the top left corner of a cell.
This is used by functions such as paintCell().
- The table coordinates. (0,0) is the top left corner of the cell at
row 0 and column 0. These coordinates are absolute; that is, they are
independent of what part of the table is visible at the moment. This is
used by functions such as setXOffset() or maxYOffset().
- The widget coordinates. (0,0) is the top left corner of the widget,
including the frame. This is used by functions such as repaint().
- The view coordinates. (0,0) is the top left corner of the view, excluding the frame. This is the least-used coordinate system, used by
functions such as viewWidth().
It is rather unfortunate that we have to use four different
coordinate systems, but if we were to provide a flexible and
powerful base class, there wasn't any way around it.
Note: The row,column indices are always given in that order,
i.e. first the vertical (row), then the horizontal (column). This is
the opposite order of all pixel operations, which take first the
horizontal (x), then the vertical (y).
Warning: the functions setNumRows(), setNumCols(), setCellHeight(),
setCellWidth(), setTableFlags() and clearTableFlags() may cause
virtual functions like cellWidth() and cellHeight() to be called,
even if autoUpdate() is FALSE. This may cause errors if relevant
state variables are not initialized.
Warning: Experience has shown that use of this widget tends to bring
more bugs than expected, and our analysis indicates that widget's
very flexibility is the problem. If QScrollView or QListBox can
easily be made to do the job you need, we recommend subclassing
those widgets rather than QTableView. In addition, QScrollView makes
it easy to have child widgets inside tables, something QTableView
doesn't support at all.
See also QScrollView and GUI Design Handbook: Table
Member Function Documentation
QTableView::QTableView ( QWidget * parent=0, const char * name=0, WFlags f=0 ) [protected]
Constructs a table view. All the arguments are passed to the QFrame
constructor.
The table flags are all cleared (set to zero).
Set Tbl_autoVScrollBar
or Tbl_autoHScrollBar
to get automatic scroll
bars and Tbl_clipCellPainting
to get safe clipping.
The cell height and cell width are set to 0.
Frame line shapes (QFrame::HLink and QFrame::VLine) are disallowed,
see QFrame::setFrameStyle().
Note that the f argument is not table
flags but rather widget
flags.
QTableView::~QTableView () [protected]
Destructs the table view.
bool QTableView::autoUpdate () const [protected]
Returns TRUE if the view updates itself automatically whenever it
is changed in some way.
See also setAutoUpdate().
int QTableView::cellHeight () const [protected]
Returns the row height, in pixels. Returns 0 if the rows have
variable heights.
See also setCellHeight() and cellWidth().
int QTableView::cellHeight ( int ) [virtual protected]
Returns the height of row row, in pixels.
This function is virtual and must be reimplemented by subclasses that
have variable cell heights. Note that if the total table height
changes, updateTableSize() must be called.
See also setCellHeight(), cellWidth() and totalHeight().
QRect QTableView::cellUpdateRect () const [protected]
This function should only be called from the paintCell() function in
subclasses. It returns the portion of a cell that actually needs to be
updated, in cell coordinates. This is only useful for non-trivial
paintCell().
int QTableView::cellWidth () const [protected]
Returns the column width, in pixels. Returns 0 if the columns have
variable widths.
See also setCellWidth() and cellHeight().
int QTableView::cellWidth ( int ) [virtual protected]
Returns the width of column col, in pixels.
This function is virtual and must be reimplemented by subclasses that
have variable cell widths. Note that if the total table width
changes, updateTableSize() must be called.
See also setCellWidth(), cellHeight(), totalWidth() and updateTableSize().
void QTableView::clearTableFlags ( uint f = ~0 ) [protected]
Clears the table flags that are set
in f.
Example (clears a single flag):
clearTableFlags( Tbl_snapToGrid );
The default argument clears all flags.
See also setTableFlags(), testTableFlags() and tableFlags().
bool QTableView::colIsVisible ( int col ) const [protected]
Returns TRUE if col is at least partially visible.
See also rowIsVisible().
bool QTableView::colXPos ( int col, int * xPos ) const [protected]
Computes the position in the widget of column column.
Returns TRUE and stores the result in *xPos (in widget
coordinates) if the column is visible. Returns FALSE and does not
modify *xPos if col is invisible or invalid.
See also rowYPos() and findCol().
int QTableView::findCol ( int xPos ) const [protected]
Returns the index of the column at position xPos, where xPos is
in widget coordinates. Returns -1 if xPos is outside the valid
range.
See also findRow() and colXPos().
int QTableView::findRow ( int yPos ) const [protected]
Returns the index of the row at position yPos, where yPos is in
widget coordinates. Returns -1 if yPos is outside the valid
range.
See also findCol() and rowYPos().
QScrollBar * QTableView::horizontalScrollBar () const [protected]
Returns a pointer to the horizontal scroll bar, mainly so you can
connect() to its signals. Note that the scroll bar works in pixel
values, use findCol() to translate to cell numbers.
int QTableView::lastColVisible () const [protected]
Returns the index of the last (right) column in the view.
The index of the first column is 0.
If no columns are visible it returns -1. This can happen if the
view is too narrow for the first column and Tbl_cutCellsH is set.
See also lastRowVisible().
int QTableView::lastRowVisible () const [protected]
Returns the index of the last (bottom) row in the view.
The index of the first row is 0.
If no rows are visible it returns -1. This can happen if the
view is too small for the first row and Tbl_cutCellsV is set.
See also lastColVisible().
int QTableView::leftCell () const [protected]
Returns the index of the first column in the table that is visible in
the view. The index of the very leftmost column is 0.
See also topCell() and setLeftCell().
int QTableView::maxColOffset () [protected]
Returns the index of the last column which may be at the left edge
of the view.
Depending on the Tbl_scrollLastHCell flag,
this may or may not be the last column.
See also maxXOffset() and maxRowOffset().
int QTableView::maxRowOffset () [protected]
Returns the index of the last row which may be at the top edge of
the view.
Depending on the Tbl_scrollLastVCell flag,
this may or may not be the last row.
See also maxYOffset() and maxColOffset().
int QTableView::maxViewX () const [protected]
Returns the rightmost pixel of the table view in view
coordinates. This excludes the frame and any scroll bar, but
includes blank pixels to the right of the visible table data.
See also maxViewY(), viewWidth() and contentsRect().
int QTableView::maxViewY () const [protected]
Returns the bottom pixel of the table view in view
coordinates. This excludes the frame and any scroll bar, but
includes blank pixels below the visible table data.
See also maxViewX(), viewHeight() and contentsRect().
int QTableView::maxXOffset () [protected]
Returns the maximum horizontal offset within the table of the
view's left edge, in table coordinates.
This is used mainly to set the horizontal scroll bar's range.
See also maxColOffset(), maxYOffset() and totalWidth().
int QTableView::maxYOffset () [protected]
Returns the maximum vertical offset within the table of the
view's top edge, in table coordinates.
This is used mainly to set the vertical scroll bar's range.
See also maxRowOffset(), maxXOffset() and totalHeight().
int QTableView::minViewX () const [protected]
Returns the leftmost pixel of the table view in view
coordinates. This excludes the frame and any header.
See also maxViewY(), viewWidth() and contentsRect().
int QTableView::minViewY () const [protected]
Returns the top pixel of the table view in view
coordinates. This excludes the frame and any header.
See also maxViewX(), viewHeight() and contentsRect().
int QTableView::numCols () const [protected]
Returns the number of columns in the table
See also numRows() and setNumCols().
int QTableView::numRows () const [protected]
Returns the number of rows in the table.
See also numCols() and setNumRows().
void QTableView::paintCell ( QPainter * p, int row, int col ) [virtual protected]
This pure virtual function is called to paint the single cell at (row,col) using p, which is open when paintCell() is called and
must remain open.
The coordinate system is translated
such that the origin is at the top left corner of the cell to be
painted; i.e. cell coordinates. Do not scale or shear the coordinate
system (or if you do, restore the transformation matrix before you
return).
By default, the painter is not clipped, for maximum efficiency. For safety,
call setTableFlags(Tbl_clipCellPainting) to enable clipping.
See also paintEvent(), QPainter() and setTableFlags().
Reimplemented in QMultiLineEdit.
void QTableView::paintEvent ( QPaintEvent * e ) [virtual protected]
Handles paint events for the table view.
Calls paintCell() for the cells that needs to be repainted.
Reimplemented from QWidget.
void QTableView::repaint ( int x, int y, int w, int h, bool erase=TRUE )
Repaints the table view directly by calling paintEvent() directly,
unless updates are disabled.
Erases the view area (x,y,w,h) if erase is TRUE. Parameters (x,y) are in widget coordinates.
If w is negative, it is replaced with width() - x
.
If h is negative, it is replaced width height() - y
.
Doing a repaint() usually is faster than doing an update(), but
calling update() many times in a row will generate a single paint
event.
At present, QTableView is the only widget that reimplements repaint(). It does this because by
clearing and then repainting one cell at at time, it can make the
screen flicker less than it would otherwise.
void QTableView::repaint ( bool erase=TRUE )
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Repaints the entire view.
void QTableView::repaint ( const QRect & r, bool erase=TRUE )
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void QTableView::resizeEvent ( QResizeEvent * ) [virtual protected]
Reimplemented for internal reasons; the API is not affected.
Reimplemented from QWidget.
bool QTableView::rowIsVisible ( int row ) const [protected]
Returns TRUE if row is at least partially visible.
See also colIsVisible().
bool QTableView::rowYPos ( int row, int * yPos ) const [protected]
Computes the position in the widget of row row.
Returns TRUE and stores the result in *yPos (in widget
coordinates) if the row is visible. Returns FALSE and does not modify
*yPos if row is invisible or invalid.
See also colXPos() and findRow().
void QTableView::scroll ( int xPixels, int yPixels ) [protected]
Moves the visible area of the table rightwards by xPixels and
downwards by yPixels pixels. Both may be negative.
Warning: You might find that QScrollView offers a higher-level of
functionality than using QTableView and this function.
This function is not the same as QWidget::scroll(), in particular,
the signs of xPixels and yPixels have the reverse semantics.
See also setXOffset(), setYOffset(), setOffset(), setTopCell(), setLeftCell() and setTopLeftOffset().
void QTableView::setAutoUpdate ( bool enable ) [virtual protected]
Sets the auto-update option of the table view to enable.
If enable is TRUE (this is the default) then the view updates itself
automatically whenever it has changed in some way (for example when a
flag is changed).
If enable is FALSE, the view does NOT repaint itself, or update
its internal state variables itself when it is changed. This can be
useful to avoid flicker during large changes, and is singularly
useless otherwise: Disable auto-update, do the changes, re-enable
auto-update, and call repaint().
Warning: Do not leave the view in this state for a long time
(i.e. between events ). If, for example, the user interacts with the
view when auto-update is off, strange things can happen.
Setting auto-update to TRUE does not repaint the view, you must call
repaint() to do this.
See also autoUpdate() and repaint().
void QTableView::setCellHeight ( int cellHeight ) [virtual protected]
Sets the height in pixels of the table cells to cellHeight.
Setting it to zero means that the row height is variable. When set
to 0 (this is the default) QTableView calls the virtual function
cellHeight() to get the height.
See also cellHeight(), setCellWidth(), totalHeight() and numRows().
void QTableView::setCellWidth ( int cellWidth ) [virtual protected]
Sets the width in pixels of the table cells to cellWidth.
Setting it to zero means that the column width is variable. When
set to 0 (this is the default) QTableView calls the virtual function
cellWidth() to get the width.
See also cellWidth(), setCellHeight(), totalWidth() and numCols().
void QTableView::setLeftCell ( int col ) [virtual protected]
Scrolls the table such that col becomes the leftmost
column. The index of the very leftmost column is 0.
See also setXOffset(), setTopLeftCell() and setTopCell().
void QTableView::setNumCols ( int cols ) [virtual protected]
Sets the number of columns of the table to cols (must be non-negative).
Does not change leftCell().
The table repaints itself automatically if autoUpdate() is set.
See also numCols(), numRows() and setNumRows().
void QTableView::setNumRows ( int rows ) [virtual protected]
Sets the number of rows of the table to rows (must be non-negative).
Does not change topCell().
The table repaints itself automatically if autoUpdate() is set.
See also numCols(), setNumCols() and numRows().
void QTableView::setOffset ( int x, int y, bool updateScrBars = TRUE ) [virtual protected]
Scrolls the table such that (x,y) becomes the top left pixel
in the view. Parameters (x,y) are in table coordinates.
The interaction with Tbl_snapTo*Grid
is tricky. If updateScrBars is TRUE, the scroll bars are
updated.
See also xOffset(), yOffset(), setXOffset(), setYOffset() and setTopLeftCell().
void QTableView::setPalette ( const QPalette & p ) [virtual]
Reimplemented for internal reasons; the API is not affected.
void QTableView::setTableFlags ( uint f ) [virtual protected]
Sets the table flags to f.
If a flag setting changes the appearance of the table the table is
repainted if and only if autoUpdate() is TRUE.
The table flags are mostly single bits, though there are some multibit
flags for convenience. Here is a complete list:
- Tbl_vScrollBar
- The table has a vertical scroll bar.
- Tbl_hScrollBar
- The table has a horizontal scroll bar.
- Tbl_autoVScrollBar
- The table has a vertical scroll bar if
and only if the table is taller than the view.
- Tbl_autoHScrollBar
- The table has a horizontal scroll bar if
and only if the table is wider than the view.
- Tbl_autoScrollBars
- The union of the previous two flags.
- Tbl_clipCellPainting
- The table uses QPainter::setClipRect() to
make sure that paintCell() will not draw outside the cell
boundaries.
- Tbl_cutCellsV
- The table will never show part of a
cell at the bottom of the table; if there is not space for all of
a cell the space is left blank.
- Tbl_cutCellsH
- The table will never show part of a
cell at the right side of the table; if there is not space for all of
a cell the space is left blank.
- Tbl_cutCells
- The union of the previous two flags.
- Tbl_scrollLastHCell
- When the user scrolls horizontally,
let him/her scroll the last cell leftward until it is at the left
edge of the view. If this flag is not set, the user can only scroll
to the point where last cell is completely visible.
- Tbl_scrollLastVCell
- When the user scrolls vertically, let
him/her scroll the last cell upward until it is at the top edge of
the view. If this flag is not set, the user can only scroll to the
point where last cell is completely visible.
- Tbl_scrollLastCell
- The union of the previous two flags.
- Tbl_smoothHScrolling
- The table scrolls as smoothly as
possible when the user scrolls horizontally. When this flag is not
set scrolling is done one cell at a time.
- Tbl_smoothVScrolling
- The table scrolls as smoothly as
possible when scrolling vertically. When this flag is not set
scrolling is done one cell at a time.
- Tbl_smoothScrolling
- The union of of previous two flags.
- Tbl_snapToHGrid
- Except when the user is actually scrolling,
the leftmost column shown snaps to the leftmost edge of the view.
- Tbl_snapToVGrid
- Except when the user is actually
scrolling, the top row snaps to the top edge of the view.
- Tbl_snapToGrid
- The union of the previous two flags.
You can specify more than one flag at a time using bitwise OR.
Example:
setTableFlags( Tbl_smoothScrolling | Tbl_autoScrollBars );
Warning: The cutCells options (Tbl_cutCells, Tbl_cutCellsH
and
Tbl_cutCellsV) may cause painting problems when scrollbars are
enabled. Do not combine cutCells and scrollbars.
See also clearTableFlags(), testTableFlags() and tableFlags().
void QTableView::setTopCell ( int row ) [virtual protected]
Scrolls the table such that row becomes the top row.
The index of the very first row is 0.
See also setYOffset(), setTopLeftCell() and setLeftCell().
void QTableView::setTopLeftCell ( int row, int col ) [virtual protected]
Scrolls the table such that the cell at row row and colum col becomes the top left cell in the view. The cell at the extreme
top left of the table is at position (0,0).
See also setLeftCell(), setTopCell() and setOffset().
void QTableView::setXOffset ( int x ) [virtual protected]
Scrolls the table such that x becomes the leftmost pixel in the view.
The x parameter is in table coordinates.
The interaction with Tbl_snapToHGrid is tricky.
See also xOffset(), setYOffset(), setOffset() and setLeftCell().
void QTableView::setYOffset ( int y ) [virtual protected]
Scrolls the table such that y becomes the top pixel in the view.
The y parameter is in table coordinates.
The interaction with Tbl_snapToVGrid is tricky.
See also yOffset(), setXOffset(), setOffset() and setTopCell().
void QTableView::setupPainter ( QPainter * ) [virtual protected]
This virtual function is called before painting of table cells
is started. It can be reimplemented by subclasses that want to
to set up the painter in a special way and that do not want to
do so for each cell.
void QTableView::show () [virtual]
Reimplemented for internal reasons; the API is not affected.
Reimplemented from QWidget.
uint QTableView::tableFlags () const [protected]
Returns the union of the table flags that are currently set.
See also setTableFlags(), clearTableFlags() and testTableFlags().
bool QTableView::testTableFlags ( uint f ) const [protected]
Returns TRUE if any of the table flags in f are currently set,
otherwise FALSE.
See also setTableFlags(), clearTableFlags() and tableFlags().
int QTableView::topCell () const [protected]
Returns the index of the first row in the table that is visible in
the view. The index of the very first row is 0.
See also leftCell() and setTopCell().
int QTableView::totalHeight () [virtual protected]
Returns the total height of the table in pixels.
This function is virtual and should be reimplemented by subclasses that
have variable cell heights and a non-trivial cellHeight() function, or a
large number of rows in the table.
The default implementation may be slow for very tall tables.
See also cellHeight() and totalWidth().
int QTableView::totalWidth () [virtual protected]
Returns the total width of the table in pixels.
This function is virtual and should be reimplemented by subclasses that
have variable cell widths and a non-trivial cellWidth() function, or a
large number of columns in the table.
The default implementation may be slow for very wide tables.
See also cellWidth() and totalHeight().
void QTableView::updateCell ( int row, int col, bool erase=TRUE ) [protected]
Repaints the cell at row row, column col if it is inside the view.
If erase is TRUE, the relevant part of the view is cleared to the
background color/pixmap before the contents are repainted.
See also isVisible().
void QTableView::updateScrollBars () [protected]
Updates the scroll bars' contents and presence to match the table's
state. Generally you should not need to call this.
See also setTableFlags().
void QTableView::updateTableSize () [protected]
Updates the scroll bars and internal state.
Call this function when the table view's total size is changed;
typically because the result of cellHeight() or cellWidth() have changed.
This function does not repaint the widget.
QScrollBar * QTableView::verticalScrollBar () const [protected]
Returns a pointer to the vertical scroll bar, mainly so you can
connect() to its signals. Note that the scroll bar works in pixel
values, use findRow() to translate to cell numbers.
int QTableView::viewHeight () const [protected]
Returns the height of the table view, as such, in view
coordinates. This does not include any header, scroll bar or frame,
but does include background pixels below the table data.
See also minViewY(), maxViewY(), viewWidth(), contentsRect() and viewRect().
QRect QTableView::viewRect () const [protected]
Returns the rectangle which is the actual table, excluding any
frame, in widget coordinates.
int QTableView::viewWidth () const [protected]
Returns the width of the table view, as such, in view
coordinates. This does not include any header, scroll bar or frame,
but does include background pixels to the right of the table data.
See also minViewX(), maxViewX(), viewHeight(), contentsRect() and viewRect().
int QTableView::xOffset () const [protected]
Returns the x coordinate in table coordinates of the pixel which is
currently on the left edge of the view.
See also setXOffset(), yOffset() and leftCell().
int QTableView::yOffset () const [protected]
Returns the y coordinate in table coordinates of the pixel which is
currently on the top edge of the view.
See also setYOffset(), xOffset() and topCell().
void QTableView::setBackgroundColor ( const QColor & c ) [virtual]
For internal use only.
Search the documentation, FAQ, qt-interest archive and more (uses
www.trolltech.com):
This file is part of the Qt toolkit,
copyright © 1995-2005
Trolltech, all rights reserved.