libgtk-3-dev software package provides development files for the GTK+ library, 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 libgtk-3-dev
libgtk-3-dev is installed in your system.
Make ensure the libgtk-3-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep libgtk-3-dev *
You will get with libgtk-3-dev package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Library development |
| Package | libgtk-3-dev |
| Version | 3.18.9-1ubuntu3 |
| Description | development files for the GTK+ library |
| Sub Section | Devel |