Xaw
Section: C Library Functions (3)
Updated: libXaw 1.0.6
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NAME
Xaw - X Athena Widgets
DESCRIPTION
Xaw
is a widget set based on the X Toolkit Intrinsics (Xt) Library. This
release by the X.org Foundation includes additions and modifications
originally made for The XFree86 Project, Inc. This manual page describes
these changes as well as some of the common interfaces between its version
and the previous X Consortium release (Xaw6).
ACTIONS
All of the Xaw widgets now have the additional translations
call-proc, declare, get-values
and set-values. The syntax for these actions is:
action-name (boolean-expression, arguments)
Action-name is one of call-proc, declare,
get-values or set-values.
Boolean-expression is composed with the operators | (or), &
(and), ^ (xor), and ~ (not). The operands can be a variable name,
which starts with a $; a resource name without the bindings .
or *; or a constant name, including mine (event->xany.window
== XtWindow(widget)), faked (event->xany.send_event != 0), true (1)
and false (0).
Arguments are self-explanatory; when starting with a $ they name
a variable, otherwise, they indicate a resource name.
- call-proc (boolean-expression, procedure-name)
-
This action allows the evaluation of a boolean expression in the first
parameter before calling a action procedure. The procedure is only called
if the expression evaluates as true. Example:
call-proc("$inside & $pressed", notify)
- declare (boolean-expression, variable, value, ...)
-
This action is used to create new variables or change their values. Any
number of variable-value tuples may be specified. Example:
declare(1, $pressed, 1)
- get-values (boolean-expression, variable, value, ...)
-
This action reads a widget resource value into a variable. Any number of
variable-value tuples may be specified. Example:
get-values(1, $fg, foreground, $bg, background)
- set-values (boolean-expression, variable, value, ...)
-
This action sets a widget resource to the given value, which may be a
variable. Any number of variable-value tuples may be specified. Example:
set-values(1, foreground, $bg, background, $fg)
Here is a sample translation to make a label widget behave like a button:
<Map>: get-values(1, $fg, foreground, $bg, background)\n\
<Btn1Down>: set-values(1, foreground, yellow, background, gray30)\n\
<Btn1Up>: set-values(1, foreground, $fg, background, $bg)
DISPLAY LISTS
All of the Xaw widgets have now the additional resource
displayList. This resource allows drawing the widget decorations
using commands embedded in a resource string. The displayList resource has
the syntax:
[class-name:]function-name arguments[[{;\n}]...]
Class-name is any registered set of functions to draw in the widget.
Currently the only existing class is xlib, which provides access to
the Xlib drawing primitives.
Function-name is the drawing or configuration function to be called,
described bellow.
Arguments may be anything suitable to the displayList function being
called. When the function requires a coordinate, the syntax is
{+-}<integer> or <integer>/<integer>. Examples:
+0,+0 top, left
-0,-0 bottom, right
-+10,-+10 bottom+10, right+10
+0,1/2 left, vertical-center
- arc-mode mode
-
Sets the arc mode. Accepted modes are "pieslice" and "chord", which
set the arc to ArcPieSlice or ArcChord, respectively. Example:
arc-mode chord
- bg color-spec
-
-
background color-spec
- Sets the background color. color-spec must a valid color
specification. Example:
background red
- cap-style style
-
Sets the cap style. Accepted styles are "notlast", "butt", "round",
and "projecting", which set the cap style to CapNotLast, CapBut, CapRound
or CapProjecting, respectively. Example:
cap-style round
- clip-mask pixmap-spec
-
Sets the pixmap for the clip mask. Requires a pixmap parameter, as
described in the PIXMAPS section below. Example:
clip-mask xlogo11
- clip-origin x,y
-
Sets the clip x and y origin. Requires two arguments, the x and y
coordinates. Example:
clip-origin 10,10
- clip-rects x1,y1,x2,y2 [...,xn,yn]
-
-
clip-rectangles x1,y1,x2,y2 [...,xn,yn]
- Sets a list of rectangles to the clip mask. The number of arguments must
be a multiple of four. The arguments are coordinates. The parser
calculates the width and height of the rectangles. Example:
clip-rects 0,0,10,20, 20,10,30,30
- coord-mode mode
-
Changes the coord mode for fill-polygon, draw-lines, and
draw-points. Accepted parameters are "modeorigin" and "previous",
that sets the coord mode to CoordModeOrigin or CoordModePrevious,
respectively. Example:
coord-mode previous
- copy-area {pixmap-spec|.},dstx,dsty[,x2,y2,srcx,srcy]
-
Calls XCopyArea. The character . means copy the window contents;
pixmap-spec is as defined in the PIXMAPS section below. X2 and
y2 are the coordinates of the end copy, not the width and height; if
not defined, the parser calculates them. src_x and src_y
default to zero. Example:
copy-area Term,10,10
- copy-plane {pixmap-spec|.},dstx,dsty[,x2,y2,srcx,srcy,plane]
-
Calls XCopyPlane. The character . means copy the window contents;
pixmap-spec is as defined in the PIXMAPS section below. X2 and
y2 are the coordinates of the end copy, not the width and height; if
not defined, the parser calculates them. src_x and src_y
default to zero. Plane defaults to one. Example:
copy-plane star,10,10
- dashes i1[...,in]
-
Sets the dashes for line drawing. Accepts up to 127 arguments. Example:
dashes 3,7 9,10
- draw-arc x1,y1,x2,y2[,start-angle,end-angle]
-
Draws an arc. The four first arguments are the rectangle enclosing the
arc. The two remaining arguments, if specified, are the start and end
angle, in degrees. Example:
draw-arc +0,+0,-1,-1,0,90
- draw-rect x1,y1,x2,y2
-
-
draw-rectangle x1,y1,x2,y2
- Draws a rectangle. Requires four arguments, which are the start and end
coordinate pairs. Example:
draw-rect +1,+1,-5,-5
- draw-string x,y,string
-
Draws a text string. Requires three arguments, a x coordinate, a y
coordinate, and a string. Strings that have white space can be quoted with
the " character; the backslash character \ can also be used,
but it will be necessary escape it twice. Example:
draw-string 10,10, "Hello world!"
- exposures boolean
-
Sets graphics exposures in the GC. Allowed parameters are a integer or the
strings "true", "false", "on" and "off". Example:
exposures true
- fill-arc x1,y1,x2,y2[,start-angle,end-angle]
-
Like draw-arc, but fills the contents of the arc with the currently
selected foreground. Example:
fill-arc +0,+0,-1,-1,0,180
- fill-poly x1,y1 [...,xn,yn]
-
-
fill-polygon x1,y1 [...,xn,yn]
- Like draw-lines, but fills the enclosed polygon and joins the first
and last point, if they are not at the same position. Example:
fill-poly +0,+10, +10,+20, +30,+0
- fill-rect x1,y1,x2,y2
-
-
fill-rectangle x1,y1,x2,y2
- Like draw-rect, but fills the contents of the rectangle with the
selected foreground color. Example:
fill-rect +10,+10,-20,-20
- fill-rule rule
-
Sets the fill rule. Accepted parameters are "evenodd" and "winding", which
set the fill rule to EvenOddRule or WindingRule, respectively. Example:
fill-rule winding
- fill-style style
-
Sets the fill style. Allowed parameters are "solid", "tiled", "stippled" and
"opaquestippled", which set the fill style to FillSolid, FillTiled,
FillStippled or FillOpaqueStippled, respectively. Example:
fill-style tiled
- font font-spec
-
Sets the font for text functions. Example:
font -*-*-*-R-*-*-*-120-*-*-*-*-ISO8859-1
- fg color-spec
-
-
foreground color-spec
- Like background, but sets the current foreground color. Example:
foreground blue
- mask
-
This command is useful when you want to draw only in the region that really
needs to be repainted. Requires no arguments.
- function function-spec
-
Sets the specific GC function. Allowed parameters are "set", "clear", "and",
"andreverse", "copy", "andinverted", "noop", "xor", "or", "nor", "equiv",
"invert", "orreverse", "copyinverted" and "nand", which set the function to
GXset, GXclear, GXand, GXandReverse, GXcopy, GXandInverted, GXnoop, GXxor,
GXor, GXnor, GXequiv, GXinvert, GXorReverse, GXcopyInverted or GXnand,
respectively. Example:
function xor
- join-style style
-
Sets the join style. Allowed parameters are "miter", "round" and "bevel",
which set the join style to JoinMiter, JoinRound and JoinBevel,
respectively. Example:
join-style round
- image {pixmap-spec},xs,ys,[xe,ye]
-
This function is implemented as a way to quickly compose complex
decorations in widgets. Pixmap-spec is as defined in the
PIXMAPS section below. xs and ys are the coordinates from
where to start copying the pixmap; xe and ye are optional (they
default to xs + pixmap.width and ys + pixmap.height, respectively). If the
pixmap has a mask, the copy is masked accordingly. Example:
image pixmap.xpm,0,0,20,20
- line x1,y1,x2,y2
-
-
draw-line x1,y1,x2,y2
- Draws a line with the current foreground color. Requires four arguments,
the starting and ending coordinate pairs. Example:
line +0,+0, -1,-1
- line-width integer
-
Selects a line width for drawing. Example:
line-width 2
- line-style style
-
Sets the line style. Accepted parameters are "solid", "onoffdash" and
"doubledash", which set the line style to LineSolid, LineOnOffDash or
LineDoubleDash, respectively. Example:
line-style onoffdash
- lines x1,y1,x2,y2 [...,xn,yn]
-
-
draw-lines x1,y1,x2,y2 [...,xn,yn]
- Draws a list of lines. Any number of argument pairs may be supplied.
Example:
lines +0,-1, -1,-1, -1,+0
- paint-string x,y,string
-
Identical to draw-string, but also uses the background color. Example:
paint-string 10,20, "Sample text"
- point x,y
-
-
draw-point x,y
- Draws a point. Requires two arguments, a coordinate pair. Example:
point +10,+10
- plane-mask integer
-
Sets the plane mask. Requires an integer parameter. Example:
plane-mask -1
- points x1,y1 [...,xn,yn]
-
-
draw-points x1,y1 [...,xn,yn]
- Draws a list of points at the specified coordinates. Example:
points +1,+2, +1,+4, +1,+6
- segments x1,y1,x2,y2 [...,xn,yn]
-
-
draw-segments x1,y1,x2,y2 [...,xn,yn]
- Draws a list of segment lines. The number of parameters must be multiple
of 4. Example:
segments +1,+2,+1,-3, +2,-2,-3,-2
- shape-mode mode
-
Sets the shape mode used in fill-polygon. Accepted parameters are
"complex", "convex" or "nonconvex", which set the shape mode to Complex,
Convex or Nonconvex, accordingly. Example:
shape-mode convex
- stipple pixmap-spec
-
Sets the pixmap for a stipple. Requires a pixmap parameter, as described
in the PIXMAPS section below. Example:
stipple plaid
- subwindow-mode mode
-
Sets the subwindow mode in the GC. Accepted parameters are
"includeinferiors" and "clipbychildren", which set the subwindow mode to
IncludeInferiors or ClipByChildren, respectively. Example:
subwindow-mode includeinferiors
- tile pixmap-spec
-
Sets the pixmap for a tile. Requires a pixmap parameter, as described
in the PIXMAPS section below. Example:
tile xlogo11?foreground=red&background=gray80
- ts-origin x,y
-
Sets the tile stipple x and y origin. Requires two arguments, a x and y
coordinate. Example:
ts-origin 10,10
- umask
-
Disables the GC mask, if it has been set with the command mask.
Requires no arguments.
Example for drawing a shadow effect in a widget:
foreground gray30;\
draw-lines +1,-1,-1,-1,-1,+1;\
foreground gray85;\
draw-lines -1,+0,+0,+0,+0,-1
PIXMAPS
A String to Pixmap converter has been added to Xaw. This converter
is meant to be extended, and has enough abstraction to allow loading
several image formats. It uses a format that resembles a URL, with
the syntax:
[type:]name[?arg=val[{&}...]]
Type can be one of bitmap, gradient or xpm.
Name may be a file name, or, in the case of type gradient, may be
either vertical or horizontal.
Arg=val is a list of arguments to the converter. An argument list is
preceded by a question mark, and multiple arguments are separated by
ampersands. The most common arguments are foreground and
background. Gradients also support the arguments start and
end (colors with which to start and end the gradient); the
steps argument, to allow using less colors; and the dimension
argument to specify the size of the gradient. The xpm converter
understands the closeness argument, which aids in using fewer colors
(useful if you have a limited colormap).
TEXT WIDGET
Most of the changes to this version of the Xaw library were done in the
TextWidget, TextSrcObject, TextSinkObject and related files.
A couple of highly visible changes in the Text widget are due to many bugs
in the Xaw6 implementation involving scrollbars and auto-resizing.
Scrollbars being added or removed caused several problems in keeping the
text cursor visible, and in Xaw6 it was very easy to have a widget thinking
the cursor was visible, when it was not. Also, permitting automatic
resizing of the widget to a larger geometry created other problems, making
it difficult to have a consistent layout in the application, and, if the
window manager did not interfere, windows larger than the screen could
result. Therefore, some functionality involving scrollbars and
auto-resizing has been disabled; see the section on new and modified
Text widget resources below.
The Text widget's default key bindings were originally based on the Emacs
text editor. In this release, even more operations familiar to Emacs users
have been added. New text actions include:
- indent
-
Indents text blocks. Not bound by default. The Text widget also does not
attempt to perform auto-indentation of its source object by default.
- keyboard-reset
-
Resets the keyboard state. Reverts the action multiplier to 1, and if undo
is enabled, toggles between undo and redo. Bound by default to
Control<Key>G.
- kill-ring-yank
-
In this version of Xaw, text killed in any text field is kept in memory,
allowing cut and paste operations internally to the program between text
fields. Bound by default to Meta<Key>Y.
- numeric
-
Listed here only for purposes of documentation. Called by default when one
of the characters 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, or - is typed,
allowing composition of the multiplication number of text actions.
- set-keyboard-focus
-
Sets the input focus of the top level widget to the text field. Not
enabled by default, but bound to the <Btn1Down> event.
- toggle-overwrite
-
Toggles overwrite mode. In overwrite mode, any text inserted in a text
field will replace existing text. Bound by default to <Key>Insert.
- undo
-
Sets the enableUndo resource of the textSrcObject. Not enabled by
default, but bound to Control<Key>_.
New and modified Text widget resources include:
- justify (Class Justify)
-
Sets the text justification. Can be one of left, right, center, or
full. Only enabled when the autoFill resource is set, and the
resources leftColumn and rightColumn are correctly set.
- leftColumn (Class Column)
-
Specifies the left column at which to break text. Text lines started with
an alphanumeric character will automatically start at this column.
- positionCallback (Class Callback)
-
Allows installation of a callback to be called every time the cursor is
moved, and/or the file changes its size. The callback is called with a
pointer to a structure containing the following data:
typedef struct {
int line_number;
int column_number;
XawTextPosition insert_position;
XawTextPosition last_position;
Boolean overwrite_mode;
} XawTextPositionInfo;
This callback is intended to help programmers write text editors based
on the Xaw widget set.
- resize (Class Resize)
-
No longer supported, but recognized for backward compatibility with
resource specifications written for the Xaw6 Text widget.
- rightColumn (Class Column)
-
Specifies the right column at which to break text. Text lines started with
an alphanumeric character will automatically end at this column.
- scrollHorizontal (Class Scroll)
-
-
scrollVertical (Class Scroll)
- These resources control the placement of scrollbars on the left and bottom
edges of the Text widget. They accept the values XawtextScrollAlways
and XawtextScrollNever. A converter is registered for this resource
that will convert the following strings: always and never. The
value XawtextScrollWhenNeeded (and whenNeeded, recognized by
the converter), is accepted for backwards compatibility with resource
specifications written for the Xaw6 Text widget, but ignored (effectively
treated as XawtextScrollNever).
TEXT SOURCE OBJECT
The textSrcObject allows display of its contents to more than one window,
and also stores undo information. The new resources for the textSrcObject
are:
- callback (Class Callback)
-
Previous versions of Xaw had this resource in subclasses of the TextSource
object. This was changed to make it possible to tell the callback the
state of the text when undo is enabled.
- enableUndo (Class Undo)
-
A boolean resource that enables or disables the undo function. The default
value is False.
- sourceChanged (Class Changed)
-
Like the callback resource, this resource was previously in subclasses of
the TextSource object. It is now in the textSrcObject to control the
changed/unchanged state when undo is enabled.
TEXT SINK OBJECT
The textSinkObject subclasses asciiSinkObject and multiSinkObject have been
changed slightly to use a new cursor shape (no longer a caret at the
baseline) that indicates the input focus of the text widget, and allow
specification of the cursor color. The new resource is:
- cursorColor (Class Color)
-
Sets the cursor color of the text. This color is also used to draw
selected text.
SIMPLE MENU WIDGET
The simpleMenuWidget algorithm to lay out menu entries has been changed to
enable multiple columns when a single column does not fit on the screen.
It was also modified to enable submenus.
SME BSB OBJECT
A new resource has been added to the smeBSBObject to allow binding submenus
to it. The new resource is:
- menuName (Class MenuName)
-
Specifies the name of the popup widget to be popped up when the pointer is
over the menu entry, or NULL. Note that the named menu must be a child of
the popup parent of the smeBSBObject.
AUTHORS
The original X Consortium version of the Athena Widget Set and its
documentation were the work of many people, including Chris D. Peterson,
Ralph Swick, Mark Ackerman, Donna Converse, Jim Fulton, Loretta
Guarino-Reid, Charles Haynes, Rich Hyde, Mary Larson, Joel McCormack, Ron
Newman, Jeanne Rich, Terry Weissman, Mike Gancarz, Phil Karlton, Kathleen
Langone, Ram Rao, Smokey Wallace, Al Mento, and Jean Diaz.
The additions and modifications to Xaw which were
originally made for XFree86 were written by Paulo
C'esar Pereira de Andrade.
SEE ALSO
Athena Widget Set - C Language Interface