chore: fix travis.yml to support recent api levels (#375)

Author: jaeopt

.travis.yml

@@ -1,48 +1,48 @@
 language: android
 # you MUST mention trusty https://docs.travis-ci.com/user/languages/android/
 dist: trusty
+jdk: oraclejdk8
+
 env:
- global:
-# These parameters should match the parameters for build tools and sdk versions in the gradle file
- - ANDROID_BUILD_TOOLS=29.0.3 # should match gradle
- - ADB_INSTALL_TIMEOUT=5 # minutes
- - ANDROID_API=29 # api is same as gradle file
- matrix:
- - EMULATOR_API=19
- - EMULATOR_API=21
- - EMULATOR_API=22
+  global:
+  - ANDROID_API=29              # api is same as gradle file
+  - ANDROID_BUILD_TOOLS=29.0.3  # should match gradle
+  - ADB_INSTALL_TIMEOUT=5       # minutes
+  matrix:
+  # API 26+ supports "x86" (ANDROID_ABI=x86) emulators only, which are not supported yet in travis VMs
+  # so API 24 is the highest level we can run with emulator for now
+  - EMULATOR_API=19 ANDROID_TAG=google_apis ANDROID_ABI=armeabi-v7a    # API-16 build fails in travis
+  - EMULATOR_API=21 ANDROID_TAG=google_apis ANDROID_ABI=armeabi-v7a
+  - EMULATOR_API=24 ANDROID_TAG=google_apis ANDROID_ABI=armeabi-v7a
+  
 android:
   components:
     - tools
-    - platform-tools-$ANDROID_BUILD_TOOLS
+    - platform-tools
     - build-tools-$ANDROID_BUILD_TOOLS
     - android-$ANDROID_API
     - android-$EMULATOR_API
+    # Google APIs
+    - addon-google_apis-google-$ANDROID_API
+    - addon-google_apis-google-$EMULATOR_API
+    # Google Play Services
+    - extra-google-google_play_services
+    # Support library
+    - extra-android-support
+    # Latest artifacts in local repository
     - extra-google-m2repository
-    - extra-android-m2repository # for design library
-    - addon-google_apis-google-19 # google play services
-    - sys-img-armeabi-v7a-addon-google_apis-google-$ANDROID_API
-    - sys-img-armeabi-v7a-addon-google_apis-google-$EMULATOR_API
-    - sys-img-armeabi-v7a-android-$EMULATOR_API
-  licenses:
-    - android-sdk-preview-license-.+
-    - android-sdk-license-.+
-    - google-gdk-license-.+
-jdk:
-  - oraclejdk8
-before_cache:
-  - rm -f $HOME/.gradle/caches/modules-2/modules-2.lock
-cache:
-  directories:
-    - $HOME/.gradle/caches/
-    - $HOME/.gradle/wrapper/
+    - extra-android-m2repository
+    # Emulators
+    - sys-img-$ANDROID_ABI-android-$EMULATOR_API
+
 before_install:
-    #- yes | sdkmanager "platforms;android-$ANDROID_API"
+  #- touch $HOME/.android/repositories.cfg
+
 before_script:
   - echo $TRAVIS_BRANCH
   - echo $TRAVIS_TAG
-  - echo no | android create avd --force -n test -t android-$EMULATOR_API --abi armeabi-v7a
-  - emulator -avd test -no-audio -no-window &
+  - echo no | android create avd --force -n test -t android-$EMULATOR_API --abi $ANDROID_ABI
+  - emulator -avd test -no-window &
   - scripts/android-wait-for-emulator.sh
   - adb shell input keyevent 82 &
 script:
@@ -102,3 +102,4 @@ jobs:
         - ./gradlew ship
       after_script: skip
       after_success: skip
+