Specifications

Athena Widget Set libXaw 1.0.7

3.10.4. Radio Groups

There are typically twotypes 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 anyToggle widgets active.

The other type of radio group is "one of many" and has the more strict policythat 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 allowany Toggle to be unset except as a result of another Toggle

becoming set.Itisthe application programmer’sresponsibility to choose an initial state for the

radio group by setting the state resource of one of its member widgets to True.

3.10.5. Convenience Routines

The following functions alloweasy access to the Toggle widget’sradio group functionality.

3.10.5.1. Changing the Toggle’sRadio Group.

To enable an application to change the Toggle’sradio group, add the Toggle to a radio group, or

remove the Toggle from a radio group, use XawToggleChangeRadioGroup.

void XawToggleChangeRadioGroup(w, radio_group)

Widget w, radio_group;

w Speciﬁes the Toggle widget.

radio_group Speciﬁes anyToggle in the newradio group. If NULL then the Toggle will be

removedfrom anyradio group of which it is a member.

If a Toggle is already set in the newradio 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 XawToggleGetCur-

rent.

XtPointer XawToggleGetCurrent(radio_group);

Widget radio_group;

radio_group Speciﬁes anyToggle widget in the radio group.

The value returned by this function is the radioData of the Toggle in this radio group that is cur-

rently 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(radio_group, radio_data);

Widget radio_group;

XtPointer radio_data;

radio_group Speciﬁes anyToggle 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.