Code Sample
output.ListStyle = EntreeListStyles.list_groups;
EntreeListGroup TheGroup = output.AddListGroup();
EntreeCheckbox TheInput = TheGroup.AddFormItem<EntreeCheckbox>("Checkbox1");
TheInput.Name = "Name";
TheInput.Checked = false;
Example Display
Note: This item style requires the ListStyle to be list_groups
Note: For a ClickActionObject to include the value entered by the user, FormSubmit must be set to true