Can't build package from developer getting started doc

Question

I'm following the developer getting started document, and have worked my way here:

http://elementary.io/docs/code/getting-started#launchpad-recipes

I'm able to build the hello-packaging application locally, but the build fails in launchpad when trying to build the deb package. The following error is under the "dpkg-buildpackage" section from the building log:

----------------------------------------------
-- Found PkgConfig: /usr/bin/pkg-config (found version "0.26") 
-- checking for module 'gtk+-3.0'
--   package 'gtk+-3.0' not found
CMake Error at /usr/share/cmake-2.8/Modules/FindPkgConfig.cmake:283 (message):
  A required package was not found
Call Stack (most recent call first):
  /usr/share/cmake-2.8/Modules/FindPkgConfig.cmake:337 (_pkg_check_modules_internal)
  CMakeLists.txt:25 (pkg_check_modules)


CMake Error at CMakeLists.txt:32 (find_package):
  By not providing "FindVala.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "Vala", but
  CMake did not find one.

  Could not find a package configuration file provided by "Vala" with any of
  the following names:

    ValaConfig.cmake
    vala-config.cmake

  Add the installation prefix of "Vala" to CMAKE_PREFIX_PATH or set
  "Vala_DIR" to a directory containing one of the above files.  If "Vala"
  provides a separate development package or SDK, be sure it has been
  installed.


-- Configuring incomplete, errors occurred!
---------------------------------------------

The directory listed in my CMAKE_MODULE_PATH does actually include "FindVala.cmake". Should I still add the PREFIX_MODULE_PATH pointing to the same place, or how would I fix this?

Answer 1

As @lemonslice said - the answer is to install the SDK package in a terminal window:

sudo apt install elementary-sdk

Did you get your app working? I'm just going through unanswered questions, and some of them are answered in comments, such as this.