Array to strings of index value pairs - arrays

Question

I would like to create a string of index and value pairs. This is to be used in dialog menu.
declare -r -a arr=(
piano
table
chair
)
dialog \
--backtitle "Launcher" \
--title "App" \
--ok-label 'Select' \
--cancel-label "Back" \
--menu "Select an application" \
$dialog_height $dialog_width 4 \
"1" "piano" \
"2" "table" \
"3" "chair"
So I'm looking to have the:
"1" "piano" \
"2" "table" \
"3" "chair"
generated automatically from array.
There's a similar question pass an array to dialog menu I tried what's there I couldn't get it to work for me.

Answer 1

To auto-generate the tags 1, 2, 3 in front of every array entry, use
items=(piano table chair)
taggedItems=()
for ((i=1; i<="${#items[#]}"; ++i)); do
taggedItems+=("$i" "${items[i-1]}")
done
# then use "${taggedItems[#]}"
Opposed to your linked awk solution, this works with arbitrary items that may contain spaces, special symbols like * and even linebreaks.

Answer 2

declare -a arr=(
''
piano
table
chair
)
unset 'arr[0]'
declare -ar arr
# Remove the echo below once ready for the fun.
echo dialog \
--backtitle "Launcher" \
--title "App" \
--ok-label 'Select' \
--cancel-label "Back" \
--menu "Select an application" \
$dialog_height $dialog_width 4 \
$(for i in "${!arr[#]}"; do echo "$i" "${arr[i]}"; done)

Answer 3

OPTIONS=(1 "table"
2 "piano"
3 "......")
dialog \
--backtitle "Launcher" \
--title "App" \
--ok-label 'Select' \
--cancel-label "Back" \
--menu "Select an application" \
$dialog_height $dialog_width 4 \
"${OPTIONS[#]}" \
2>&1 >/dev/tty

Answer 4

There are two ways, using simple array:
#!/bin/bash
declare -r -a arr=(
piano
table
chair
)
options=$(printf '%s\n' "${arr[#]}" | awk '{print v++,$arr}')
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
$options \
2>&1 >/dev/tty
Or with associative array:
#!/bin/bash
declare -r -A arr=(
piano
table
chair
)
options=$(printf '%s\n' "${!arr[#]}" | awk '{print v++,$arr}')
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
$options \
2>&1 >/dev/tty
To start menu numbers at 1:
#!/bin/bash
declare -r -a arr=(
piano
table
chair
)
options=$(printf '%s\n' "${arr[#]}" | awk -v v=1 '{print v++,$arr}')
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
$options \
2>&1 >/dev/tty
To use both key and value of associative array in menu:
#!/bin/bash
declare -r -A arr=(
[piano]=piano
[table]=mesa
[chair]=cadeira
)
options=$(printf "%s\n" "${!arr[#]} " "${arr[#]}")
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
$options \
2>&1 >/dev/tty

Answer 5

Correct answer works both with normal and associative arrays of entries, using numerical index or associative key as menu key:
Normal array of menu entries, using numerical index as menu key:
#!/usr/bin/env bash
arr=(
piano
table
chair
)
options=()
for k in "${!arr[#]}"; do
options+=( "$k" "${arr[$k]}" )
done
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
"${options[#]}" \
>/dev/tty 2>&1
Full example with associative array:
#!/usr/bin/env bash
declare -A assoc=(
[p]=piano
[t]=table
[c]=chair
)
options=()
for k in "${!assoc[#]}"; do
options+=("$k" "${assoc[$k]}")
done
choice="$(
dialog \
--backtitle "Test" \
--title "Test" \
--menu "Test" \
0 0 4 \
"${options[#]}" \
2>&1 >/dev/tty
)"
clear
case $choice in
t)
printf %s\\n "Let's set the table."
;;
p)
printf %s\\n "Let's play piano."
;;
c)
printf %s\\n "Let's sit dow."
;;
*)
printf %s\\n "Let's decide later."
;;
esac