github actions to build apk

.github/workflows/build.yml

@@ -0,0 +1,55 @@
+name: timerAndroid CI Workflow
+
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - 'v*'
+
+jobs:
+  apk:
+    name: Generate APK
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+      - name: Setup JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 1.8
+      - name: Build APK
+        run: bash ./gradlew assembleDebug --stacktrace
+      - name: Upload APK
+        uses: actions/upload-artifact@v1
+        with:
+          name: apk
+          path: app/build/outputs/apk/debug/app-debug.apk 
+  release:
+    name: Release APK
+    needs: apk
+    if: startsWith(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download APK from build
+        uses: actions/download-artifact@v1
+        with:
+          name: apk  
+      - name: Create Release
+        id: create_release
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} 
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: Release ${{ github.ref }} 
+      - name: Upload Release APK
+        id: upload_release_asset
+        uses: actions/[email protected]
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: apk/app-debug.apk
+          asset_name: timerAndroid.apk
+          asset_content_type: application/zip