Installing the prerequisite
Since GTK+ is a C library, we'll need to install it first. The Rust bindings use GTK+ version 3, so make sure you do not install the old version 2.
Installing GTK+ on Linux
On Linux, GTK+ can be installed through the package manager of your distribution.
On Ubuntu (or other Debian derivatives):
sudo apt-get install libgtk-3-dev
Installing GTK+ on Mac
On OSX, you just need to run the following command:
brew install gtk+3 gnome-icon-theme
Installing GTK+ on Windows
On Windows, you'll need to first download and install MSYS2, which provides a Unix-like environment on Windows. After it is installed, issue the following command in a MSYS2 shell:
pacman -S mingw-w64-x86_64-gtk3