Android continuous integration using Travis CI (build, unit tests and connected tests using AVD)

AndroidTravisCIWithAVD.travis.yml

sudo: required

language: android
jdk: oraclejdk8

before_cache:
  - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
  - rm -rf $HOME/.gradle/caches/*/plugin-resolution/
  
cache:
  directories:
  - $HOME/.gradle/caches/
  - $HOME/.gradle/wrapper/
  - $HOME/.android/build-cache
  
env:
 global:
 - ANDROID_API_LEVEL=26
 - ANDROID_BUILD_TOOLS=26.0.2
 - ANDROID_EMU_API_LEVEL=21   
 - ANDROID_ABI=armeabi-v7a
 - ADB_INSTALL_TIMEOUT=20 # minutes (2 minutes by default)
 - QEMU_AUDIO_DRV=none # Remove audio

android:
  components:
  - tools
  - tools # Running this twice get's the latest build tools (https://github.com/codepath/android_guides/wiki/Setting-up-Travis-CI)
  - platform-tools
  - android-$ANDROID_API_LEVEL
  - build-tools-$ANDROID_BUILD_TOOLS
  - android-$ANDROID_EMU_API_LEVEL
  - extra
  - sys-img-$ANDROID_ABI-google_apis-$ANDROID_EMU_API_LEVEL
  
before_script:
- echo no | android create avd --force -n test -t android-$ANDROID_EMU_API_LEVEL --abi google_apis/$ANDROID_ABI
- emulator -avd test -no-window &
- android-wait-for-emulator
- adb shell input keyevent 82 &

script:
 - android list target
 - ./gradlew clean test build
 - ./gradlew connectedCheck