appstream-index software package provides Transitional package (appstream-index -> appstream), you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install appstream-index
appstream-index is installed in your system.
Make ensure the appstream-index package were installed using the commands given below,
$ sudo dpkg-query -l | grep appstream-index *
You will get with appstream-index package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Administration Utilities |
| Package | appstream-index |
| Version | 0.9.4-1 |
| Description | Transitional package (appstream-index -> appstream) |
| Sub Section | admin |