Test hello-world example with Android Emulator on CI

.github/workflows/android_test.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+set -e
+
+rustup target install x86_64-linux-android
+cargo install --path "$GITHUB_WORKSPACE/cargo-apk" --force
+cd "$GITHUB_WORKSPACE/ndk-examples"
+cargo apk run --example hello_world --target x86_64-linux-android
+
+sleep 30s
+
+adb logcat *:E hello-world:V -d > ~/logcat.log
+
+if grep 'hello world' ~/logcat.log;
+then
+    echo "App running"
+else
+    echo "::error::App not running"
+    exit 1
+fi
+
+ERROR_MSG=$(grep -e 'thread.*panicked at' "$HOME"/logcat.log | true)
+if [ -z "${ERROR_MSG}" ];
+then
+    exit 0
+else
+    echo "::error::${ERROR_MSG}"
+    exit 1
+fi

.github/workflows/emulator.yml

@@ -0,0 +1,25 @@
+name: Android Emulator
+
+on: [push, pull_request]
+
+jobs:
+  android_emulator:
+      runs-on: macos-10.15
+      steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Run tests
+        uses: reactivecircus/android-emulator-runner@v2
+        with:
+          api-level: 29
+          arch: x86_64
+          # the `googleapis` emulator target is considerably slower on CI.
+          target: default
+          profile: Nexus 5X
+          script: bash ./.github/workflows/android_test.sh
+      - uses: actions/upload-artifact@master
+        if: ${{ always() }}
+        with:
+          name: log
+          path: |
+            ~/logcat.log

ndk-examples/Cargo.toml

@@ -18,3 +18,7 @@ crate-type = ["cdylib"]
 [[example]]
 name = "jni_audio"
 crate-type = ["cdylib"]
+
+[package.metadata.android.sdk]
+min_sdk_version = 16
+target_sdk_version = 29