how to compile gtk+ programs?

[Star Liu <minxinjianxin@gmail.com>]

I'm trying to build a sample gtk+ program on debian sid amd64, by
following the tutorial from gtk.org, but get this error:

Desktop:~/eclipseworkspace/DebianCPlus/src# gcc -o Gtk Gtk.c
`pkg-config --libs --cflags gtk+2.0`
Package gtk+2.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gtk+2.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'gtk+2.0' found

I have installed libgtk2.0-dev, how to resolve the error? thanks.