Extend README

README.md

@@ -9,3 +9,44 @@ No inputs are needed.
 ## Outputs
 
 No outputs are generated apart from configured problem matchers.
+
+## Example usage
+
+In your workflow YAML file add this step:
+
+```yaml
+    - name: Setup Android problem matchers
+      uses: jonasb/android-problem-matchers-action@v1
+```
+
+Example full workflow definition:
+
+```yaml
+name: Android CI
+on: [push]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: Setup JDK 1.8
+      uses: actions/setup-java@v1
+      with:
+        java-version: 1.8
+    - name: Setup Android problem matchers
+      uses: jonasb/android-problem-matchers-action@v1
+    - name: Build Android
+      run: |
+        ./gradlew build -PisCI=true
+```
+
+In order for Android Lint problems (especially warnings) to show up in the logs and be detected, make these changes to `app/build.gradle`:
+
+```groovy
+android {
+  lintOptions {
+    textReport project.hasProperty('isCI')
+    textOutput 'stdout'
+  }
+}
+```