Toggle Widget
Application Header file <Xaw/Toggle.h>
Class Header file <Xaw/ToggleP.h>
Class toggleWidgetClass
Class Name Toggle
Superclass Command
The Toggle widget is an area, often rectangular,
that displays a graphic. The graphic may be a text
string containing multiple lines of characters in an 8
bit or 16 bit character set (to be displayed with a
font), or in a multi-byte encoding (for use with
a fontset). The graphic may also be a bitmap or
pixmap.
This widget maintains a Boolean state (e.g.
True/False or On/Off) and changes state whenever it is selected. When
the pointer is on the Toggle widget, the Toggle widget may become highlighted by
drawing a rectangle around its perimeter. This highlighting indicates
that the Toggle widget is ready for selection. When pointer button 1 is
pressed and released, the Toggle widget indicates that it has changed
state by reversing its foreground and background colors, and its
notify action is invoked, calling all functions on its callback
list. If the pointer is moved off of the widget before the pointer button is
released, the Toggle widget reverts to its previous foreground and background
colors, and releasing the pointer button has no effect. This behavior allows
the user to cancel the operation.
Toggle widgets may also be part of a ``radio group.'' A radio group is a
list of at least two Toggle widgets in which no more than one Toggle may
be set at
any time. A radio group is identified by the widget ID of any one of
its members. The convenience routine XawToggleGetCurrent will
return information about the Toggle widget in the radio group.
Toggle widget state is preserved across changes in sensitivity.
Resources
When creating a Toggle widget instance, the following resources are
retrieved from the argument list or from the resource database:
Name
Class
Type
Notes
Default Value
accelerators
Accelerators
AcceleratorTable
NULL
ancestorSensitive
AncestorSensitive
Boolean
D
True
background
Background
Pixel
XtDefaultBackground
backgroundPixmap
Pixmap
Pixmap
XtUnspecifiedPixmap
bitmap
Bitmap
Pixmap
None
borderColor
BorderColor
Pixel
XtDefaultForeground
borderPixmap
Pixmap
Pixmap
XtUnspecifiedPixmap
borderWidth
BorderWidth
Dimension
1
callback
Callback
XtCallbackList
NULL
colormap
Colormap
Colormap
Parent's Colormap
cornerRoundPercent
CornerRoundPercent
Dimension
25
cursor
Cursor
Cursor
None
cursorName
Cursor
String
NULL
depth
Depth
int
C
Parent's Depth
destroyCallback
Callback
XtCallbackList
NULL
encoding
Encoding
UnsignedChar
XawTextEncoding8bit
font
Font
XFontStruct
XtDefaultFont
fontSet
FontSet
XFontSet
XtDefaultFontSet
foreground
Foreground
Pixel
XtDefaultForeground
height
Height
Dimension
A
graphic height + 2 * internalHeight
highlightThickness
Thickness
Dimension
A
2 (0 if Shaped)
insensitiveBorder
Insensitive
Pixmap
GreyPixmap
internalHeight
Height
Dimension
2
internalWidth
Width
Dimension
4
international
International
Boolean
C
False
justify
Justify
Justify
XtJustifyCenter (center)
label
Label
String
name of widget
leftBitmap
LeftBitmap
Bitmap
None
mappedWhenManaged
MappedWhenManaged
Boolean
True
pointerColor
Foreground
Pixel
XtDefaultForeground
pointerColorBackground
Background
Pixel
XtDefaultBackground
radioData
RadioData
Pointer
Name of widget
radioGroup
Widget
Widget
No radio group
resize
Resize
Boolean
True
screen
Screen
Screen
R
Parent's Screen
sensitive
Sensitive
Boolean
True
shapeStype
ShapeStyle
ShapeStyle
Rectangle
state
State
Boolean
Off
translations
Translations
TranslationTable
See below
width
Width
Dimension
A
graphic width + 2 * internalWidth
x
Position
Position
0
y
Position
Position
0
radioData
Specifies the data that will be returned by XawToggleGetCurrent
when this is the currently set widget in the radio group. This
value is also used to identify the Toggle that will be set by a call to
XawToggleSetCurrent. The value NULL will be returned by
XawToggleGetCurrent if no widget in a radio group is currently
set. Programmers must not specify NULL (or Zero) as radioData.
radioGroup
Specifies another Toggle widget that is in the radio group to which this
Toggle widget should be added. A radio group is a group of at least two Toggle
widgets, only one of which may be set at a time. If this value is
NULL (the default) then the Toggle will not be part of any radio group
and can change state without affecting any other Toggle widgets. If the
widget specified in this resource is not already in a radio group then a
new radio group will be created containing these two Toggle widgets. No
Toggle widget can be in multiple radio groups. The behavior of a radio
group of one toggle is undefined. A converter is registered which will
convert widget names to widgets without caching.
state
Specifies whether the Toggle widget is set (True) or unset
(False).
Toggle Actions
The Toggle widget supports the following actions:
Switching the Toggle widget between the foreground and background
colors with set and unset and toggle
Processing application callbacks with notify
Switching the internal border between highlighted
and unhighlighted states with highlight and unhighlight
The following are the default translation bindings used by the
Toggle widget:
<EnterWindow>: highlight(Always)
<LeaveWindow>: unhighlight()
<Btn1Down>,<Btn1Up>: toggle() notify()
Toggle Actions_b
The full list of actions supported by Toggle is:
highlight(condition)
Displays the internal highlight border in the color (foreground
or background ) that contrasts with the interior color of the
Toggle widget. The conditions WhenUnset and Always are
understood by this action procedure. If no argument is passed then
WhenUnset is assumed.
unhighlight()
Displays the internal highlight border in the color (foreground
or background ) that matches the interior color of the
Toggle widget.
set()
Enters the set state, in which notify is possible. This
action causes the Toggle widget to display its interior in the
foreground color. The label or bitmap is displayed in the
background color.
unset()
Cancels the set state and displays the interior of the Toggle widget in the
background color. The label or bitmap is displayed in the
foreground color.
toggle()
Changes the current state of the Toggle widget, causing to be set
if it was previously unset, and unset if it was previously set.
If the widget is to be set, and is in a radio group then this procedure may
unset another Toggle widget causing all routines on its callback list
to be invoked. The callback routines for the Toggle that
is to be unset will be called before the one that is to be set.
reset()
Cancels any set or highlight and displays the interior of the
Toggle widget in the background color, with the label displayed in the
foreground color.
notify()
When the Toggle widget is in the set state this action calls all functions in
the callback list named by the callback resource. The value of
the call_data argument in these callback functions is undefined.
When a bitmap of depth greater that one (1) is specified the
set(), unset(), and reset() actions have no effect,
since there are no foreground and background colors used in a
multi-plane pixmap.
Radio Groups
There are typically two types of radio groups desired by applications.
The default translations for the Toggle widget implement a "zero or one
of many" radio group. This means that there may be no more than one
Toggle widget active, but there need not be any Toggle widgets active.
The other type of radio group is "one of many" and has the more strict
policy that there will always be exactly one radio button active.
Toggle widgets can be used to provide this interface with a slight
modification to the translation table of each Toggle in the group.
<EnterWindow>: highlight(Always)
<LeaveWindow>: unhighlight()
<Btn1Down>,<Btn1Up>: set() notify()
This translation table will not allow any Toggle to be unset
except as a result of another Toggle becoming set. It is
the application programmer's responsibility to choose an initial
state for the radio group by setting the state resource of one of
its member widgets to True.
Convenience Routines
The following functions allow easy access to the Toggle widget's radio
group functionality.
Changing the Toggle's Radio Group.
To enable an application to change the Toggle's radio group, add
the Toggle to a radio group, or remove the Toggle from a radio group, use
XawToggleChangeRadioGroup.
void XawToggleChangeRadioGroup
Widgetw, radio_group
w
Specifies the Toggle widget.
radio_group
Specifies any Toggle in the new radio group. If NULL then the Toggle
will be removed from any radio group of which it is a member.
If a Toggle is already set in the new radio group,
and the Toggle to be added is also set then the previously
set Toggle in the radio group is unset and its callback
procedures are invoked.
Finding the Currently selected Toggle in a radio group of Toggles
To find the currently selected Toggle in a radio group of Toggle widgets
use XawToggleGetCurrent.
XtPointer XawToggleGetCurrent
XtPointer XawToggleGetCurrent(radio_group)
Widget radio_group
radio_group
Specifies any Toggle widget in the radio group.
The value returned by this function is the
radioData
of the Toggle in this radio group that is currently set. The default
value for radioData
is the name of that Toggle widget. If no Toggle is set in the radio
group specified then NULL is returned.
Changing the Toggle that is set in a radio group.
To change the Toggle that is currently set in a radio group use
XawToggleSetCurrent.
void XawToggleSetCurrent
voidXawToggleSetCurrent(radio_group, radio_data)
Widget radio_group
XtPointer radio_data
radio_group
Specifies any Toggle widget in the radio group.
radio_data
Specifies the
radioData
identifying the Toggle that should be set in the radio group specified
by the radio_group argument.
XawToggleSetCurrent locates the Toggle widget to be set by
matching radio_data against the radioData for each Toggle in
the radio group. If none match, XawToggleSetCurrent returns
without making any changes. If more than one Toggle matches,
XawToggleSetCurrent will choose a Toggle to set arbitrarily. If
this causes any Toggle widgets to change state, all routines in their
callback lists will be invoked. The callback routines for a Toggle that
is to be unset will be called before the one that is to be set.
Unsetting all Toggles in a radio group.
To unset all Toggle widgets in a radio group use
XawToggleUnsetCurrent.
void XawToggleUnsetCurrent
void XawToggleUnsetCurrent(radio_group)
Widget radio_group
radio_group
Specifies any Toggle widget in the radio group.
If this causes a Toggle widget to change state, all routines on its
callback list will be invoked.