Checkbox groups are collections of checkboxes with the special
property that no more than one checkbox in the same group can be
selected at a time. The checkboxes in a CheckboxGroup
are often called radio buttons. Checkboxes that are members of the
same CheckboxGroup cannot be checked simultaneously.
When the user checks one, all others are unchecked automatically.
The constructor for a CheckboxGroup is trivial. No
arguments are needed. You do not even need to add the
CheckboxGroup to the applet since checkbox groups are
themselves not user-interface widgets, just ways of arranging
checkboxes.
CheckboxGroup cbg = new CheckboxGroup();
To make check boxes act like radio buttons, use this
constructor
for each Checkbox in the group.
public Checkbox(String label, CheckboxGroup cbg, boolean
checked)
The label is the
label for this Checkbox. The
CheckboxGroup is the group you want this
Checkbox to belong to and must already exist.
At any time, you can get or set the selected
Checkbox with these two methods:
public Checkbox getSelectedCheckbox()
public void setSelectedCheckbox(Checkbox box)