NAME
Prima::Grids - grid widgets
SYNOPSIS
use Prima::Grids;
$grid = Prima::Grid-> create(
cells => [
[qw(1.First 1.Second 1.Third)],
[qw(2.First 2.Second 2.Third)],
[qw(3.First 3.Second 3.Third)],
],
onClick => sub {
print $_[0]-> get_cell_text( $_[0]-> focusedCell), " is selected\n";
}
);
DESCRIPTION
The module provides classes for several abstraction layers of grid
representation. The classes hierarchy is as follows:
AbstractGridViewer
AbstractGrid
GridViewer
Grid
The root class, "Prima::AbstractGridViewer", provides common interface,
while by itself it is not directly usable. The main differences
between classes are centered around the way the cell data are stored.
The simplest organization of a text-only cell, provided by
"Prima::Grid", stores data as a two-dimensional array of text scalars.
More elaborated storage and representation types are not realized, and
the programmer is urged to use the more abstract classes to derive own
mechanisms. To organize an item storage, different from "Prima::Grid",
it is usually enough to overload either the "Stringify", "Measure", and
"DrawCell" events, or their method counterparts: "get_cell_text",
"columnWidth", "rowHeight", and "draw_items".
The grid widget is designed to contain cells of variable extents, of
two types, normal and indent. The indent rows and columns are displayed
in grid margins, and their cell are drawn with distinguished colors.
An example use for a bottom indent row is a sum row in a spreadsheet
application; the top indent row can be used for displaying columns’
headers. The normal cells can be selected by the user, scrolled, and
selected. The cell selection can only contain rectangular areas, and
therefore is operated with two integer pairs with the beginning and the
end of the selection.
The widget operates in two visual scrolling modes; when the space
allows, the scrollbars affect the leftmost and the topmost cell. When
the widget is not large enough to accommodate at least one cell and all
indent cells, the layout is scrolled pixel-wise. These modes are named
’cell’ and ’pixel’, after the scrolling units.
The widget allows the interactive changing of cell widths and heights
by dragging the grid lines between the cells.
Prima::AbstractGridViewer
"Prima::AbstractGridViewer", the base for all grid widgets in the
module, provides interface to generic grid browsing functionality, plus
functionality for text-oriented grids. The class is not usable
directly.
"Prima::AbstractGridViewer" is a descendant of "Prima::GroupScroller",
and some properties are not described here. See "Prima::GroupScroller"
in Prima::IntUtils.
Properties
allowChangeCellHeight BOOLEAN
If 1, the user is allowed to change vertical extents of cells by
dragging the horizontal grid lines. Prerequisites to the options
are: the lines must be set visible via "drawHGrid" property,
"constantCellHeight" property set to 0, and the changes to the
vertical extents can be recorded via "SetExtent" notification.
Default value: 0
allowChangeCellWidth BOOLEAN
If 1, the user is allowed to change horizontal extents of cells by
dragging the horizontal grid lines. Prerequisites to the options
are: the lines must be set visible via "drawVGrid" property,
"constantCellWidth" property set to 0, and the changes to the
horizontal extents can be recorded via "SetExtent" notification.
Default value: 0
cellIndents X1, Y1, X2, Y2
Marks the marginal rows and columns as ’indent’ cells. The indent
cells are drawn with another color pair ( see indentCellColor,
indentCellBackColor ), cannot be selected and scrolled. X1 and X2
correspond to amount of indent columns, and Y1 and Y2, - to the
indent rows.
"leftCell" and "topCell" do not count the indent cells as the
leftmost or topmost visible cell; in other words, X1 and Y1 are
minimal values for "leftCell" and "topCell" properties.
Default value: 0,0,0,0
clipCells INTEGER
A three-state integer property, that governs the way clipping is
applied when cells are drawn. Depending on kind of graphic in
cells, the clipping may be necessary, or unnecessary.
If the value is 1, the clipping is applied for every column drawn,
as the default drawing routines proceed column-wise. If the value
is 2, the clipping as applied for every cell. This setting reduces
the drawing speed significantly. If the value is 0, no clipping is
applied.
This property is destined for custom-drawn grid widgets, when it is
the developer’s task to decide what kind of clipping suits better.
Text grid widgets, "Prima::AbstractGrid" and "Prima::Grid", are
safe with "clipCells" set to 1.
Default value: 1
columns INTEGER
Sets number of columns, including the indent columns. The number of
columns must be larger than the number of indent columns.
Default value: 0.
columnWidth COLUMN [ WIDTH ]
A run-time property, selects width of a column. To acquire or set
the width, "Measure" and "SetExtent" notifications can be invoked.
Result of "Measure" may be cached internally using
"cache_geometry_requests" method.
The width does not include widths of eventual vertical grid lines.
If "constantCellWidth" is defined, the property is used as its
alias.
constantCellHeight HEIGHT
If defined, all rows have equal height, HEIGHT pixels. If "undef",
rows have different heights.
Default value: undef
constantCellWidth WIDTH
If defined, all rows have equal width, WIDTH pixels. If "undef",
columns have different widths.
Default value: undef
drawHGrid BOOLEAN
If 1, horizontal grid lines between cells are drawn with
"gridColor".
Default value: 1
drawVGrid
If 1, vertical grid lines between cells are drawn with "gridColor".
Default value: 1
dx INTEGER
A run-time property. Selects horizontal offset in pixels of grid
layout in pixel mode.
dy INTEGER
A run-time property. Selects vertical offset in pixels of grid
layout in pixel mode.
focusedCell X, Y
Selects coordinates or the focused cell.
gridColor COLOR
Selects the color of grid lines.
Default value: "cl::Black" .
gridGravity INTEGER
The property selects the breadth of area around the grid lines,
that reacts on grid-dragging mouse events. The minimal value, 0,
marks only grid lines as the drag area, but makes the dragging
operation inconvenient for the user. Larger values make the
dragging more convenient, but increase the chance that the user
will not be able to select too narrow cells with the mouse.
Default value: 3
indentCellBackColor COLOR
Selects the background color of indent cells.
Default value: "cl::Gray" .
indentCellColor
Selects the foreground color of indent cells.
Default value: "cl::Gray" .
leftCell INTEGER
Selects index of the leftmost visible normal cell.
multiSelect BOOLEAN
If 1, the normal cells in an arbitrary rectangular area can be
marked as selected ( see selection ). If 0, only one cell at a time
can be selected.
Default value: 0
rows INTEGER
Sets number of rows, including the indent rows. The number of rows
must be larger than the number of indent rows.
Default value: 0.
topCell
Selects index of the topmost visible normal cell.
rowHeight INTEGER
A run-time property, selects height of a row. To acquire or set the
height, "Measure" and "SetExtent" notifications can be invoked.
Result of "Measure" may be cached internally using
"cache_geometry_requests" method.
The height does not include widths of eventual horizontal grid
lines.
If "constantCellHeight" is defined, the property is used as its
alias.
selection X1, Y1, X2, Y2
If "multiSelect" is 1, governs the extents of a rectangular area,
that contains selected cells. If no such area is present, selection
is (-1,-1,-1,-1), and "has_selection" returns 0 .
If "multiSelect" is 0, in get-mode returns the focused cell, and
discards the parameters in the set-mode.
Methods
cache_geometry_requests CACHE
If CACHE is 1, starts caching results of "Measure" notification,
thus lighting the subsequent "columnWidth" and "rowHeight" calls;
if CACHE is 0, flushes the cache.
If a significant geometry change was during the caching, the cache
is not updated, so it is the caller’s responsibility to flush the
cache.
deselect_all
Nullifies the selection, if "multiSelect" is 1.
draw_cells CANVAS, COLUMNS, ROWS, AREA
A bulk draw routine, called from "onPaint" to draw cells. AREA is
an array of four integers with inclusive-inclusive coordinates of
the widget inferior without borders and scrollbars ( result of
get_active_area(2) call; see "get_active_area" in Prima::IntUtils
).
COLUMNS and ROWS are structures that reflect the columns and rows
of the cells to be drawn. Each item in these corresponds to a
column or row, and is an array with the following layout:
0: column or row index
1: type; 0 - normal cell, 1 - indent cell
2: visible cell breadth
3: visible cell start
4: visible cell end
5: real cell start
6: real cell end
The coordinates are in inclusive-inclusive coordinate system, and
do not include eventual grid space, nor gaps between indent and
normal cells. By default, internal arrays "{colsDraw}" and
"{rowsDraw}" are passed as COLUMNS and ROWS parameters.
In "Prima::AbstractGrid" and "Prima::Grid" classes <draw_cells> is
overloaded to transfer the call to "std_draw_text_cells", the text-
oriented optimized routine.
draw_text_cells SCREEN_RECTANGLES, CELL_RECTANGLES, CELL_INDECES,
FONT_HEIGHT
A bulk routine for drawing text cells, called from
"std_draw_text_cells" .
SCREEN_RECTANGLES and CELL_RECTANGLES are arrays, where each item
is a rectangle with exterior of a cell. SCREEN_RECTANGLES contains
rectangles that cover the cell visible area; CELL_RECTANGLES
contains rectangles that span the cell extents disregarding its
eventual partial visibility. For example, a 100-pixel cell with
only its left half visible, would contain corresponding arrays
[150,150,200,250] in SCREEN_RECTANGLES, and [150,150,250,250] in
CELL_RECTANGLES.
CELL_INDECES contains arrays of the cell coordinates; each array
item is an array of integer pair where item 0 is column, and item 1
is row of the cell.
FONT_HEIGHT is a current font height value, cached since
"draw_text_cells" is often used for text operations and may require
vertical text justification.
get_cell_area [ WIDTH, HEIGHT ]
Returns screen area in inclusive-inclusive pixel coordinates, that
is used to display normal cells. The extensions are related to the
current size of a widget, however, can be overridden by specifying
WIDTH and HEIGHT.
get_cell_text COLUMN, ROW
Returns text string assigned to cell in COLUMN and ROW. Since the
class does not assume the item storage organization, the text is
queried via "Stringify" notification.
get_range AXIS, INDEX
Returns a pair of integers, minimal and maximal breadth of INDEXth
column or row in pixels. If AXIS is 1, the rows are queried; if 0,
the columns.
The method calls "GetRange" notification.
get_screen_cell_info COLUMN, ROW
Returns information about a cell in COLUMN and ROW, if it is
currently visible. The returned parameters are indexed by
"gsci::XXX" constants, and explained below:
gsci::COL_INDEX - visual column number where the cell displayed
gsci::ROW_INDEX - visual row number where the cell displayed
gsci::V_FULL - cell is fully visible
gsci::V_LEFT - inclusive-inclusive rectangle of the visible
gsci::V_BOTTOM part of the cell. These four indices are grouped
gsci::V_RIGHT under list constant, gsci::V_RECT.
gsci::V_TOP
gsci::LEFT - inclusive-inclusive rectangle of the cell, as if
gsci::BOTTOM it is fully visible. These four indices are grouped
gsci::RIGHT under list constant, gsci::RECT. If gsci::V_FULL
gsci::TOP is 1, these values are identical to these in gsci::V_RECT.
If the cell is not visible, returns empty array.
has_selection
Returns a boolean value, indicating whether the grid contains a
selection (1) or not (0).
point2cell X, Y, [ OMIT_GRID = 0 ]
Return information about point X, Y in widget coordinates. The
method returns two integers, CX and CY, with cell coordinates, and
eventual HINTS hash, with more information about pixe localtion. If
OMIT_GRID is set to 1 and the pixel belongs to a grid, the pixels
is treated a part of adjacent cell. The call syntax:
( $CX, $CY, %HINTS) = $self->point2cell( $X, $Y);
If the pixel lies within cell boundaries by either coordinate, CX
and/or CY are correspondingly set to cell column and/or row. When
the pixel is outside cell space, CX and/or CY are set to -1.
HINTS may contain the following values:
"x" and "y"
If 0, the coordinate lies within boundaries of a cell.
If -1, the coordinate is on the left/top to the cell body.
If +1, the coordinate is on the right/bottom to the cell body,
but within the widget.
If +2, the coordinate is on the right/bottom to the cell body,
but outside the widget.
"x_type" and "y_type"
Present when "x" or "y" values are 0.
If 0, the cell is a normal cell.
If -1, the cell is left/top indent cell.
If +1, the cell is right/bottom indent cell.
"x_grid" and "y_grid"
If 1, the point is over a grid line. This case can only happen
when OMIT_GRID is 0. If "allowChangeCellHeight" and/or
"allowChangeCellWidth" are set, treats also "gridGravity"-broad
pixels strips on both sides of the line as the grid area.
Also values of "x_left"/"x_right" or "y_bottom"/"y_top" might
be set.
"x_left"/"x_right" and "y_bottom"/"y_top"
Present together with "x_grid" or "y_grid". Select indices of
cells adjacent to the grid line.
"x_gap" and "y_gap"
If 1, the point is within a gap between the last normal cell
and the first right/bottom indent cell.
"normal"
If 1, the point lies within the boundaries of a normal cell.
"indent"
If 1, the point lies within the boundaries of an indent cell.
"grid"
If 1, the point is over a grid line.
"exterior"
If 1, the point is in inoperable area or outside the widget
boundaries.
redraw_cell X, Y
Repaints cell with coordinates X and Y.
reset
Recalculates internal geometry variables.
select_all
Marks all cells as selected, if "multiSelect" is 1.
std_draw_text_cells CANVAS, COLUMNS, ROWS, AREA
An optimized bulk routine for text-oriented grid widgets. The
optimization is achieved under assumption that each cell is drawn
with two colors only, so the color switching can be reduced.
The routine itself paints the cells background, and calls
"draw_text_cells" to draw text and/or otherwise draw the cell
content.
For explanation of COLUMNS, ROWS, and AREA parameters see
draw_cells .
Events
DrawCell CANVAS, COLUMN, ROW, INDENT, @SCREEN_RECT, @CELL_RECT,
SELECTED, FOCUSED
Called when a cell with COLUMN and ROW coordinates is to be drawn
on CANVAS. SCREEN_RECT is a cell rectangle in widget coordinates,
where the item is to be drawn. CELL_RECT is same as SCREEN_RECT,
but calculated as if the cell is fully visible.
SELECTED and FOCUSED are boolean flags, if the cell must be drawn
correspondingly in selected and focused states.
GetRange AXIS, INDEX, MIN, MAX
Puts minimal and maximal breadth of INDEXth column ( AXIS = 0 ) or
row ( AXIS = 1) in corresponding MIN and MAX scalar references.
Measure AXIS, INDEX, BREADTH
Puts breadth in pixels of INDEXth column ( AXIS = 0 ) or row ( AXIS
= 1) into BREADTH scalar reference.
This notification by default may be called from within
"begin_paint_info/end_paint_info" brackets. To disable this feature
set internal flag "{NoBulkPaintInfo}" to 1.
SelectCell COLUMN, ROW
Called when a cell with COLUMN and ROW coordinates is focused.
SetExtent AXIS, INDEX, BREADTH
Reports breadth in pixels of INDEXth column ( AXIS = 0 ) or row (
AXIS = 1), as a response to "columnWidth" and "rowHeight" calls.
Stringify COLUMN, ROW, TEXT_REF
Puts text string, assigned to cell with COLUMN and ROW coordinates,
into TEXT_REF scalar reference.
Prima::AbstractGrid
Exactly the same as its ascendant, "Prima::AbstractGridViewer", except
that it does not propagate "DrawItem" message, assuming that the items
must be drawn as text.
Prima::GridViewer
The class implements cells data and geometry storage mechanism, but
leaves the cell data format to the programmer. The cells are accessible
via "cells" property and several other helper routines.
The cell data are stored in an array, where each item corresponds to a
row, and contains array of scalars, where each corresponds to a column.
All data managing routines, that accept two-dimensional arrays, assume
that the columns arrays are of the same widths.
For example, "[[1,2,3]]]" is a valid one-row, three-column structure,
and "[[1,2],[2,3],[3,4]]" is a valid three-row, two-column structure.
The structure "[[1],[2,3],[3,4]]" is invalid, since its first row has
one column, while the others have two.
"Prima::GridViewer" is derived from "Prima::AbstractGridViewer".
Properties
allowChangeCellHeight
Default value: 1
allowChangeCellWidth
Default value: 1
cell COLUMN, ROW, [ DATA ]
Run-time property. Selects the data in cell with COLUMN and ROW
coordinates.
cells [ ARRAY ]
The property accepts or returns all cells as a two-dimensional
rectangular array or scalars.
columns INDEX
A read-only property; returns number of columns.
rows INDEX
A read-only property; returns number of rows.
Methods
add_column CELLS
Inserts one-dimensional array of scalars to the end of columns.
add_columns CELLS
Inserts two-dimensional array of scalars to the end of columns.
add_row CELLS
Inserts one-dimensional array of scalars to the end of rows.
add_rows CELLS
Inserts two-dimensional array of scalars to the end of rows.
delete_columns OFFSET, LENGTH
Removes LENGTH columns starting from OFFSET. Negative values are
accepted.
delete_rows OFFSET, LENGTH
Removes LENGTH rows starting from OFFSET. Negative values are
accepted.
insert_column OFFSET, CELLS
Inserts one-dimensional array of scalars as column OFFSET.
Negative values are accepted.
insert_columns OFFSET, CELLS
Inserts two-dimensional array of scalars in column OFFSET.
Negative values are accepted.
insert_row
Inserts one-dimensional array of scalars as row OFFSET. Negative
values are accepted.
insert_rows
Inserts two-dimensional array of scalars in row OFFSET. Negative
values are accepted.
Prima::Grid
Descendant of "Prima::GridViewer", declares format of cells as a single
text string. Incorporating all functionality of its ascendants,
provides a standard text grid widget.
Methods
get_cell_text COLUMN, ROW
Returns text string assigned to cell in COLUMN and ROW. Since the
item storage organization is implemented, does so without calling
"Stringify" notification.
AUTHOR
Dmitry Karasik, <dmitry@karasik.eu.org>.
SEE ALSO
Prima, Prima::Widget, examples/grid.pl