Input 7

What I've done:
Part of the assignment asks to have a GUI interface and to allow the user to input directories. I've spent the last workshop, creating a GUI with output, I will later implement the java I have been working on.
script:
#!/bin/bash
DIALOG_CANCEL=1
DIALOG_ESC=255
HEIGHT=0
WIDTH=0

display_result() {
  dialog --title "$1" \
    --no-collapse \
    --msgbox "$result" 0 0
}

while true; do
  exec 3>&1
  selection=$(dialog \
    --backtitle "System Information" \
    --title "Menu" \
    --clear \
    --cancel-label "Exit" \
    --menu "Please select:" $HEIGHT $WIDTH 4 \
    "1" "Directory Selection" \
    "2" "Run Program" \
    "3" "Current Directory" \
    2>&1 1>&3)
  exit_status=$?
  exec 3>&-
  case $exit_status in
    $DIALOG_CANCEL)
      clear
      echo "Program terminated."
      exit
      ;;
    $DIALOG_ESC)
      clear
      echo "Program aborted." >&2
      exit 1
      ;;
  esac
  case $selection in
    0 )
      clear
      echo "Program terminated."
      ;;
    1 )
      DIALOG=${DIALOG=dialog}

FILE=`$DIALOG --stdout --title "Please choose a file" --fselect $HOME/ 14 48`

case $? in
        0)
                echo "\"$FILE\" chosen";;
        1)
                echo "Cancel pressed.";;
        255)
                echo "Box closed.";;
esac

      ;;
    2 )

	du -h -m --max-depth=1 $FILE > mapped.txt
       sleep 5 
	result=$(cat mapped.txt)
	display_result "mapped"
      ;;
    3 )
       tcdialog --title 'test 3' --msgbox mapped.txt 100 50
      
      ;;
  esac
done

Output:

What needs to be done next:
I need to implement my java program into this