title: How do you fix "Build failed: Android SDK dir was not specified, exiting."
body: <p>I am trying to build a kivy apk and I keep getting this error, " Build failed: Android SDK dir was not specified, exiting.". What do I need to do to fix it?</p>
  
  <p>and when i run:</p>
  
  <pre><code> python3 -m pythonforandroid.toolchain create --dist_name=simpleapp --bootstrap=sdl2 --requirements=python3,kivy,android --arch armeabi-v7a --copy-libs --color=always --storage-dir="/home/haryo/kivy-game-2.0/.buildozer/android/platform/build" --ndk-api=21
  </code></pre>
  
  <p>i get:</p>
  
  <pre><code>[INFO]:    Will compile for the following archs: armeabi-v7a
  [ERROR]:   Build failed: Android SDK dir was not specified, exiting.
  </code></pre>