ALSO SEE https://www.ej-technologies.com/resources/install4j/help/doc/concepts/dmgStyling.html
First create a dmg with no DS_Store (or an existing one if you just want to edit one)
cp ../../build/install4j/11/Jalview-OFFLINE_macos-app_DEVELOPMENT-j11.dmg ./temp.dmg
hdiutil convert temp.dmg -format UDRW -o temp_rw.dmg
If you are creating a new dmg, or want to add more files than remaining space, then you will need to add some capacity to the dmg. If you're just doing small edits then you might get away without the following block of commands used to resize the dmg.
CURSIZE=`hdiutil resize temp_rw.dmg | perl -n -e 'm/^\s*\d+\s+(\d+)\s+\d+$/ && print "$1\n";'`
NEWSIZE=$(( CURSIZE + 20000))
hdiutil resize -sectors $NEWSIZE temp_rw.dmg
Continue by opening the dmg in Finder. The /Volumes/...
folder will depend on the dmg you're editing.
open temp_rw.dmg
open /Volumes/Jalview\ Installer
Then manually position/resize icons, extend size of Finder window, etc so that the Finder window looks how you want it. You can use the
cp /Volumes/Jalview\ Installer/.DS_Store ./DS_Store_N
umount /Volumes/Jalview\ Installer
See file README-DMG_background_image_creation.md
on how to create the background image.
See https://www.ej-technologies.com/resources/install4j/help/doc/concepts/dmgStyling.html which describes how to add the background image to your DMG file using macOS Finder.
Worth exploring further: