Binding Groups of Components to Fields
When you create a button group in a form that is bound to source code, no field for the group is created. If you need to reference the group in code, you will have to explicitly bind the group to a field.
To bind a button group to a field
Select the button group in the Component Treeview. The group's properties appear in the Inspector pane.
Make sure the value in the Name property is the name you want for the new field in the source code.
Check the Bind to field checkbox to generate the field declaration in the source file bound to the parent GUI form.