Fix minimal-winit-android build. (#430)

* Fix `minimal-winit-android` build.

Allows the example to correctly run as a binary on desktop platforms.

Includes a container that avoids dependency management hell with the
Android SDK. And basic instructions for using it.

* Add Android CI support

Author: parasyte

.github/workflows/ci.yml

@@ -22,10 +22,10 @@ jobs:
       - name: Install dependencies
         run: sudo apt -y install libgtk-3-dev libudev-dev libxdo-dev
       - name: Install toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ matrix.rust }}
-          target: wasm32-unknown-unknown
+          targets: wasm32-unknown-unknown,armv7-linux-androideabi,aarch64-linux-android
       - name: Rust cache
         uses: Swatinem/rust-cache@v2
         with:
@@ -34,6 +34,10 @@ jobs:
         run: cargo check --workspace
       - name: Cargo check WASM
         run: cargo check --target wasm32-unknown-unknown --package minimal-web
+      - name: Cargo check Android ARMv7
+        run: cargo check --target armv7-linux-androideabi --package minimal-winit-android --lib
+      - name: Cargo check Android AARCH64
+        run: cargo check --target aarch64-linux-android --package minimal-winit-android --lib
 
   lints:
     name: Lints
@@ -46,11 +50,11 @@ jobs:
       - name: Install dependencies
         run: sudo apt -y install libgtk-3-dev libudev-dev libxdo-dev
       - name: Install toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: stable
           components: clippy, rustfmt
-          target: wasm32-unknown-unknown
+          targets: wasm32-unknown-unknown,armv7-linux-androideabi,aarch64-linux-android
       - name: Rust cache
         uses: Swatinem/rust-cache@v2
         with:
@@ -67,6 +71,10 @@ jobs:
         run: cargo clippy --workspace --tests -- -D warnings
       - name: Cargo clippy WASM
         run: cargo clippy --target wasm32-unknown-unknown --package minimal-web --tests -- -D warnings
+      - name: Cargo clippy Android ARMv7
+        run: cargo clippy --target armv7-linux-androideabi --package minimal-winit-android --lib -- -D warnings
+      - name: Cargo clippy Android AARCH64
+        run: cargo clippy --target aarch64-linux-android --package minimal-winit-android --lib -- -D warnings
       - name: Cargo machete
         run: cargo machete
 
@@ -88,7 +96,7 @@ jobs:
       - name: Install dependencies
         run: sudo apt -y install libgtk-3-dev libudev-dev libxdo-dev
       - name: Install toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ matrix.rust }}
       - name: Rust cache
@@ -110,17 +118,54 @@ jobs:
       - name: Checkout sources
         uses: actions/checkout@v3
       - name: Install toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: stable
-          target: wasm32-unknown-unknown
+          targets: wasm32-unknown-unknown
       - name: Rust cache
         uses: Swatinem/rust-cache@v2
         with:
           shared-key: common
       - name: WASM build
         run: cargo run-wasm --build-only --package ${{ matrix.example }}
 
+  android:
+    name: Android
+    runs-on: ubuntu-latest
+    needs: [checks, lints]
+    strategy:
+      matrix:
+        example:
+          - minimal-winit-android
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@v3
+      - name: Install toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          targets: armv7-linux-androideabi,aarch64-linux-android
+      - name: Set up JDK 17
+        uses: actions/setup-java@v3
+        with:
+          java-version: '17'
+          distribution: 'temurin'
+      - name: Setup Android SDK
+        uses: android-actions/setup-android@v3
+        with:
+          cmdline-tools-version: 13114758
+          packages: build-tools;35.0.1 ndk;28.2.13676358 platforms;android-35
+      - name: Rust cache
+        uses: Swatinem/rust-cache@v2
+        with:
+          shared-key: common
+      - name: Install cargo-apk
+        uses: baptiste0928/cargo-install@v2
+        with:
+          crate: cargo-apk
+      - name: Android build
+        run: cargo apk build --package ${{ matrix.example }} --lib
+
   # See https://github.com/parasyte/pixels-ci-rust-version
   rust-version:
     name: Rust-Version
@@ -136,7 +181,7 @@ jobs:
         with:
           repository: parasyte/pixels-ci-rust-version
       - name: Install toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ matrix.rust }}
       - name: Rust cache

Cargo.lock

@@ -0,0 +1,2 @@
+# Ignore everything
+*

examples/minimal-winit-android/.dockerignore

@@ -14,11 +14,23 @@ winit = { workspace = true, features = ["android-native-activity"] }
 env_logger.workspace = true
 
 [target.'cfg(target_os = "android")'.dependencies]
-android_logger = "0.11.0"
+android_logger = "0.15.0"
+
+[[bin]]
+# Rename the bin to avoid https://github.com/rust-lang/cargo/issues/6313
+name = "desktop-example"
+path = "src/main.rs"
 
 [lib]
-crate-type = ["cdylib"]
+crate-type = ["cdylib", "lib"]
 
 [package.metadata.android.signing.release]
 path = "./path/to/KeyStoreFile.jks"
 keystore_password = "password"
+
+[package.metadata.android]
+build_targets = ["armv7-linux-androideabi", "aarch64-linux-android"]
+
+[package.metadata.android.sdk]
+min_sdk_version = 23
+target_sdk_version = 35

examples/minimal-winit-android/Cargo.toml

@@ -0,0 +1,50 @@
+# Build with the `pixels` MSRV. This will be updated in lockstep.
+FROM rust:1.82.0-slim
+
+# Variable arguments
+ARG JAVA_VERSION=17
+ARG NDK_VERSION=28.2.13676358
+ARG BUILDTOOLS_VERSION=35.0.1
+ARG PLATFORM_VERSION=android-35
+ARG CLITOOLS_VERSION=13114758_latest
+
+# Install Android requirements
+RUN apt-get update -yqq && \
+    apt-get install -y --no-install-recommends \
+    libcurl4-openssl-dev libssl-dev pkg-config build-essential git python3 wget zip unzip openjdk-${JAVA_VERSION}-jdk && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
+
+# Install android targets
+RUN rustup target add armv7-linux-androideabi aarch64-linux-android
+
+# Install cargo-apk
+RUN cargo install --locked cargo-apk
+
+# Generate Environment Variables
+ENV JAVA_VERSION=${JAVA_VERSION}
+ENV ANDROID_HOME=/opt/Android
+ENV NDK_HOME=/opt/Android/ndk/${NDK_VERSION}
+ENV ANDROID_NDK_ROOT=${NDK_HOME}
+ENV PATH=$PATH:${ANDROID_HOME}:${ANDROID_NDK_ROOT}:${ANDROID_HOME}/build-tools/${BUILDTOOLS_VERSION}:${ANDROID_HOME}/cmdline-tools/bin
+
+# Install command line tools
+RUN mkdir -p ${ANDROID_HOME}/cmdline-tools && \
+    wget -qc "https://dl.google.com/android/repository/commandlinetools-linux-${CLITOOLS_VERSION}.zip" -P /tmp && \
+    unzip -d ${ANDROID_HOME} /tmp/commandlinetools-linux-${CLITOOLS_VERSION}.zip && \
+    rm -fr /tmp/commandlinetools-linux-${CLITOOLS_VERSION}.zip
+# Install sdk requirements
+RUN echo y | sdkmanager --sdk_root=${ANDROID_HOME} --install \
+    "build-tools;${BUILDTOOLS_VERSION}" "ndk;${NDK_VERSION}" "platforms;${PLATFORM_VERSION}"
+
+# Create APK keystore for debug profile
+# Adapted from https://github.com/rust-mobile/cargo-apk/blob/caa806283dc26733ad8232dce1fa4896c566f7b8/ndk-build/src/ndk.rs#L393-L423
+RUN keytool -genkey -v -keystore ${HOME}/.android/debug.keystore -storepass android -alias androiddebugkey \
+    -keypass android -dname 'CN=Android Debug,O=Android,C=US' -keyalg RSA -keysize 2048 -validity 10000
+
+# Cleanup
+RUN rm -rf /tmp/*
+
+WORKDIR /mnt
+
+ENTRYPOINT [ "cargo", "apk", "build", "--lib" ]

examples/minimal-winit-android/Containerfile

@@ -4,15 +4,51 @@
 
 Minimal example to run on android using `winit` with `android-native-activity` feature
 
-## Running
-```
+## Running on Android
+
+```bash
 export ANDROID_HOME="path/to/sdk"
 export ANDROID_NDK_HOME="path/to/ndk"
 
 rustup target add aarch64-linux-android
 cargo install cargo-apk
 ```
+
 Connect your Android device via USB cable to your computer in debug mode and run the following command
+
+```bash
+cargo apk run --package minimal-winit-android
+```
+
+## Running on Desktop
+
+Sometimes it is helpful to run your Android apps on a Desktop environment (e.g., Windows, macOS, or
+Linux). It works the same way as all other `pixels` examples:
+
+```bash
+cargo run --package minimal-winit-android
+```
+
+## Containerized Builds
+
+A `Containerfile` is included, allowing containerized builds without the need to install the Android
+SDK and dependencies on the build host.
+
+The following commands are assumed to be run from the repository root directory.
+
+Build the image in Docker:
+
+```bash
+docker build -t rust-android:latest ./examples/minimal-winit-android/
 ```
-cargo apk run
+
+Build the example in the container:
+
+```bash
+docker run --rm -it -v "$PWD:/src" rust-android:latest --package minimal-winit-android
 ```
+
+The APKs are written to `./target/debug/apk/`.
+
+For release builds, add `--release` to the end of the `run` command. (This will need the path to
+the keystore corrected in the Cargo.toml manifest.) The APKs are written to `./target/release/apk/`.

examples/minimal-winit-android/README.md

@@ -1,5 +1,5 @@
 #![deny(clippy::all)]
-#![forbid(unsafe_code)]
+#![cfg_attr(not(target_os = "android"), forbid(unsafe_code))]
 
 #[cfg(target_os = "android")]
 use winit::platform::android::activity::AndroidApp;
@@ -22,14 +22,13 @@ struct World {
     velocity_y: i16,
 }
 
-struct Display<'win> {
+struct Display {
     window: Arc<Window>,
-    pixels: Pixels<'win>,
+    pixels: Pixels<'static>,
 }
 
-fn _main(event_loop: EventLoop<()>) {
-    let mut display: Option<Display> = None;
-
+pub fn _main(event_loop: EventLoop<()>) {
+    let mut display = None;
     let mut world = World::new();
 
     let res = event_loop.run(|event, elwt| {
@@ -52,10 +51,17 @@ fn _main(event_loop: EventLoop<()>) {
             Event::Suspended => {
                 display = None;
             }
+            Event::WindowEvent {
+                event: WindowEvent::CloseRequested,
+                ..
+            } => {
+                elwt.exit();
+            }
             Event::WindowEvent {
                 event: WindowEvent::RedrawRequested,
                 ..
             } => {
+                world.update();
                 if let Some(display) = &mut display {
                     world.draw(display.pixels.frame_mut());
                     display.pixels.render().unwrap();
@@ -64,9 +70,6 @@ fn _main(event_loop: EventLoop<()>) {
             }
             _ => {}
         }
-        if display.is_some() {
-            world.update();
-        }
     });
     res.unwrap();
 }
@@ -119,25 +122,18 @@ impl World {
     }
 }
 
-#[allow(dead_code)]
 #[cfg(target_os = "android")]
 #[no_mangle]
 fn android_main(app: AndroidApp) {
+    use android_logger::Config;
+    use winit::event_loop::EventLoopBuilder;
     use winit::platform::android::EventLoopBuilderExtAndroid;
-    android_logger::init_once(android_logger::Config::default().with_min_level(log::Level::Info));
-    let event_loop = EventLoopBuilder::new().with_android_app(app).build();
-    log::info!("Hello from android!");
-    _main(event_loop);
-}
 
-#[allow(dead_code)]
-#[cfg(not(target_os = "android"))]
-fn main() {
-    env_logger::builder()
-        .filter_level(log::LevelFilter::Info) // Default Log Level
-        .parse_default_env()
-        .init();
-    let event_loop = EventLoop::new().unwrap();
-    log::info!("Hello from desktop!");
+    android_logger::init_once(Config::default().with_max_level(log::LevelFilter::Info));
+    let event_loop = EventLoopBuilder::new()
+        .with_android_app(app)
+        .build()
+        .unwrap();
+    log::info!("Hello from android!");
     _main(event_loop);
 }