#!/bin/bash

cmd=(dialog --separate-output --checklist "Select options:" 22 76 16)
options=(
   1 "Check disk space" on
   2 "List users currently logged in" off
   3 "Show system uptime" off
)
choices=$("${cmd[@]}" "${options[@]}" 2>&1 >/dev/tty)
clear
for choice in $choices
do
   case $choice in
       1)
           df -h
           ;;
       2)
           who
           ;;
       3)
           uptime
           ;;
   esac
done