| Radiobuttons are identical to Checkbox's but grouped so that only one in a group can be on at a time. They use same class for buttons but add CheckboxGroup class |
| CheckboxGroup cbg = new CheckboxGroup(); // cbg is group for one set of radiobuttons |
| add(new Checkbox("Red", cbg, false)); // cbg is second argument!! |
| add(new Checkbox("Green", cbg, false)); |
| add(new Checkbox("Blue", cbg, true)); // Only one in group cbg can be true |