PREFAB-COMPOUND(2) PREFAB-COMPOUND(2)
NAME
prefab: Compound - windows for ITV toolkit
SYNOPSIS
include "draw.m";
include "prefab.m";
prefab := load Prefab Prefab->PATH;
Compound: adt
{
image: ref Draw->Image;
environ: ref Environ;
r: Draw->Rect;
title: ref Element;
contents: ref Element;
iconbox: fn(env: ref Environ,
p: Draw->Point, title: string, icon,
mask: ref Draw->Image):
ref Compound;
textbox: fn(env: ref Environ,
r: Draw->Rect, title, text: string):
ref Compound;
layoutbox: fn(env: ref Environ,
r: Draw->Rect, title: string, lay: list of Layout):
ref Compound;
box: fn(env: ref Environ,
p: Draw->Point, title, elist: ref Element):
ref Compound;
draw: fn(comp: self ref Compound);
redraw: fn(comp: self ref Compound, r: Draw->Rect);
scroll: fn(comp: self ref Compound, elem: ref Element,
d: Draw->Point);
show: fn(comp: self ref Compound, elem: ref Element): int;
select: fn(comp: self ref Compound,
elem: ref Element, i: int, c: chan of int):
(int, int, ref Element);
tagselect: fn(comp: self ref Compound,
elem: ref Element, i: int, c: chan of int):
(int, int, ref Element);
highlight: fn(comp: self ref Compound,
elem: ref Element, on: int);
};
DESCRIPTION
Compound is the data type defining boxes drawn on the
screen. Each appears in a new window, Compound.image, and
holds a (possibly nil) title Element and contents Element.
It occupies the space on the screen defined by Compound.r.
Allocating a Compound creates a window but does not draw it;
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PREFAB-COMPOUND(2) PREFAB-COMPOUND(2)
after the Compound is built, Compound.draw must be called to
make it visible. Compounds have a border around them, drawn
in Style.edgecolor and contain from top to bottom the title
(if any), a horizontal line (if there is a title), and the
contents.
Compound.iconbox(env, p, title, icon, mask)
Creates a Compound whose contents are made by calling
Element.icon (see prefab-element(2)) using the icon and
mask. The Compound's upper left corner is at p; its
size is determined by the size of the icon and mask.
Compound.textbox(env, r, title, text)
Creates a Compound whose contents are made by calling
Element.text using the supplied text. As with
Element.text, the resulting contents Element will be
actually a list of text Elements if the text occupies
multiple lines on the screen. The rectangle behaves as
in Element.text.
Compound.layoutbox(env, r, title, layoutlist)
Like Compound.textbox, but based on Element.layout
rather than Element.text.
Compound.box(env, p, title, element)
Creates a Compound whose contents are made from an
existing Element. To build complex structures, use the
Element-building functions, size the Element appropri-
ately, and use Compound.box. The result is positioned
with its upper left corner at p, and with size deter-
mined by that of the Element.
However a Compound is built, its size computation makes
allowance for the border and title. Moreover, if the
requested size and placement makes part appear offscreen,
the result may be moved to display it better.
Compound.draw()
This function uses the description of the title and
contents to paint the on-screen image. It takes no
arguments; all the information is included in the
description.
Compound.redraw(r)
Like Compound.draw, but restricts the drawing to the
specified Rect r.
Compound.select( element, index, c ): (int, int, Element)
The channel c is a chan of int connected to an IR
remote control interface, typically acquired through
the program's Context (see draw-context(2)). The
element is contained in the Compound, and may be at any
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level of its structure. It is most usefully a list,
but may be a singleton, in which case it behaves like a
list of one element. The arrow keys on the remote con-
trol scroll through the members of the list, using the
Style.highlightcolor associated with each member ele-
ment to indicate selection. A Select key on the remote
control triggers select to return a tuple (key, index,
elem); key is the key code of the action (here Select),
index is the number of the element in the list (ignor-
ing separators), and elem is the list member high-
lighted when the key was hit. Any other key returns
the same tuple with index -1 and the value of the key.
The elem returned is always the most recently high-
lighted, even if the result was not a selection. When
select returns, it always restores the default appear-
ance of the list.
Compound.tagselect( element, index, c): (int, int, Element)
Like Compound.select, but rather than selecting among
all the elements of a list, it selects among only those
elements with defined tags in the structure contained
within the specified element.
Compound.highlight(element, on)
Set the highlighting to be ``on'' or ``off'' for the
element within the compound.
Compound.scroll(element, d)
Like Element.scroll: scroll the element within the com-
pound. The updated image is redrawn after the scrol-
ling.
Compound.show(element, d)
Like Element.show: make sure the element is visible
within the rectangle of the top-level Element of the
Compound, that is, in effect call
Element.show(Compound.contents, element);
SOURCE
/libinterp/prefab.c
/libprefab/*.c
SEE ALSO
prefab-element(2), prefab-environ(2), prefab-style(2)
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