#!/bin/bash
FILES=($(ls -1))
Total_Files=${#FILES[@]}
Index=0
Count=0
while [ $Index -lt $Total_Files ];do
        [ $Count -eq 20 ] && { read -p 'Press the Enter/Return Key to Continue...';Count=0; }
        echo $Index : ${FILES[$Index]}
        let 'Index++'
        let 'Count++'
done
exit 0

echo ${FILES[$Index]}

FILES=($(ls -1))

read -p 'Press the Enter/Return Key to Continue...'

$ select file in $(seq 1 20); do echo $file; done
1) 1     3) 3    5) 5    7) 7    9) 9   11) 11  13) 13  15) 15  17) 17  19) 19
2) 2     4) 4    6) 6    8) 8   10) 10  12) 12  14) 14  16) 16  18) 18  20) 20
#?

dialog --fselect ./ $height $width # will make a nice dialog to select a file
dialog --menu "Select operation:" $height $width $menu_height \
1 "delete" \
2 "move" \
3 "do something else with the file"

#!/bin/bash

FILES_PER_SCREEN=20

select_file() {

	# some useful variables
	FILES=($(ls -1)) # breaks if filenames contain spaces
	Total_Files=${#FILES[@]}
	CHOICE1=""

	while [ x"$CHOICE1" = x ]; do
		Index=0
		Count=0

		# print all the files line by line
		while [ $Index -lt $Total_Files ];do

			# if the screen is full wait for the user to either select a file or continue
       		 	[ $Count -eq $FILES_PER_SCREEN ] && {
		       		read -p 'Press the Enter/Return Key to Continue...' CHOICE1;
			       	Count=0;

				# check that the input is an integer
				[ x"$(echo "$CHOICE1"|tr -d [0-9])" = "x" ] || CHOICE1=""

				# if the user selected a file, exit loop
				[ x"$CHOICE1" == "x" ] || break
			}
		        echo $Index : ${FILES[$Index]}
		        let 'Index++'
		        let 'Count++'
		done
	done

	# store the filename in the variable passed as $1
	eval $1=${FILES[$CHOICE1]}
}

select_file FILENAME
echo "Your choice is: $FILENAME"

select OPERATION in delete move copy; do
	[ "$OPERATION" = "delete" ] && rm "$FILENAME"
	# add the code to be done here...
done
exit 0

#!/bin/bash

# let's have an array
declare -a FILES 

# this might be a bit strange way to load those names into an array, but it will probably
# deal with the spaces correctly. I don't know if there's a point to this -- it's like 
# 4am and I haven't got a clue about what I'm doing
for file in *; do FILES+=("$file"); done

# some variables --------------------------------------

# Number of files to print at a time
FILES_PER_SCREEN=20

# Number of files to move up and down when user selects
# "previous" or "next"
STEP=20

# our current position in the list -- index of the
# first filename to display
POS=0

# Total number of files in current directory
FILE_NUMBER=${#FILES[@]}

# index of the last filename to display
ENDPOS=$FILES_PER_SCREEN
[[ ENDPOS -ge FILE_NUMBER ]] && (( ENDPOS=$FILE_NUMBER - 1 ))

# Now let's store the entire array of available files in a string
# If there are files behind $ENDPOS, include the 'next' option
OPTIONS=$(for i in $(seq $POS $ENDPOS); do echo "${FILES[$i]}"; done;
	(( ($ENDPOS + 1) < FILE_NUMBER )) && echo "next")

# To check if the user wants to quit the program
QUIT=FALSE

# to treat only newlines as field separators ( so the names
# containing spaces don't break up
IFS='
'

# Main loop ===========================================
# will run until user chooses to quit
while [ x"$QUIT" = xFALSE ]; do
        clear
        # The outer select loop -------------------------------
	select SELECTED in $OPTIONS; do

                # Move down in the list
		if [ x"$SELECTED" = xnext ]; then
       			(( POS = $POS + $STEP ))
			(( ENDPOS = $FILES_PER_SCREEN + $POS ))
			[[ ENDPOS -ge FILE_NUMBER ]] && (( ENDPOS=$FILE_NUMBER - 1 ))
			OPTIONS=$([ "$POS" -gt 0 ] && echo "previous";  for i in $(seq $POS $ENDPOS); do
                                echo "${FILES[$i]}"; done;
				(( ($ENDPOS + 1) < FILE_NUMBER )) && echo "next")
			break
                # Move up in the list
		elif [ x"$SELECTED" = xprevious ]; then
			if [ "$POS" -le "$STEP" ]; then POS=0;
			else (( POS = $POS - $STEP )); fi
			(( ENDPOS = $FILES_PER_SCREEN + $POS ))
			[[ ENDPOS -ge FILE_NUMBER ]] && (( ENDPOS=$FILE_NUMBER - 1 ))
			OPTIONS=$([ "$POS" -gt 0 ] && echo "previous";  for i in $(seq $POS $ENDPOS); do
                                echo "${FILES[$i]}"; done;
				(( ($ENDPOS + 1) < FILE_NUMBER )) && echo "next")
			break
		elif [ x"$SELECTED" = x ]; then
			break;

		else
                        # inner select loop ......................................................
			select OPERATION in delete move quit; do
				if [ x"$OPERATION" = x ]; then continue
				elif [ x"$OPERATION" = xdelete ]; then
					rm "$SELECTED"
				elif [ x"$OPERATION" = xquit ]; then exit 0
				else 
					echo "$OPERATION" # code to be executed
				fi
			done
                        # end of inner select .....................................................
		fi

	done
        # end of outer select ----------------------------------------------

done
# end of main loop ===============================================