Use example on Gitlab's blog

.gitlab-ci.yml

@@ -1,11 +1,32 @@
 image: ubuntu:jammy
 
+# https://about.gitlab.com/blog/2018/10/24/setting-up-gitlab-ci-for-android-projects/
+variables:
+  ANDROID_COMPILE_SDK: "28"
+  ANDROID_BUILD_TOOLS: "28.0.2"
+  ANDROID_SDK_TOOLS:   "4333796"
+
+before_script:
+    - apt-get update -y
+    - apt-get install -y wget tar unzip lib32stdc++6 lib32z1
+    - wget --output-document=android-sdk.zip https://dl.google.com/android/repository/sdk-tools-linux-${ANDROID_SDK_TOOLS}.zip
+    - unzip -d android-sdk-linux android-sdk.zip
+    - echo y | android-sdk-linux/tools/bin/sdkmanager "platforms;android-${ANDROID_COMPILE_SDK}"
+    - echo y | android-sdk-linux/tools/bin/sdkmanager "platform-tools"
+    - echo y | android-sdk-linux/tools/bin/sdkmanager "build-tools;${ANDROID_BUILD_TOOLS}"
+    - export ANDROID_HOME=$PWD/android-sdk-linux
+    - export PATH=$PATH:$PWD/android-sdk-linux/platform-tools/
+    # temporarily disable checking for EPIPE error and use yes to accept all licenses
+    - set +o pipefail
+    - yes | android-sdk-linux/tools/bin/sdkmanager --licenses
+    - set -o pipefail
+
+stages:
+    - build
+
 assembleDebug:
     stage: build
-    script: |
-      apt update
-      DEBIAN_FRONTEND=noninteractive apt install -y openjdk-11-jre
-      ./gradlew assembleDebug
+    script: ./gradlew assembleDebug
     artifacts:
         paths:
             - app/build/outputs/apk/debug/*.apk