WIP support compiling example/hello_world for Android

examples/hello_world/Cargo.toml

@@ -10,3 +10,10 @@ publish = false
 
 [dependencies]
 eframe = { path = "../../eframe" }
+
+# This dependency will only be included when targeting Android
+[target.'cfg(target_os = "android")'.dependencies]
+ndk-glue = "0.6.2"
+
+[lib]
+crate-type = ["lib", "cdylib"]

examples/hello_world/README.md

@@ -1,3 +1,29 @@
+## Linux, MacOS, Windows
+
 ```sh
 cargo run -p hello_world
 ```
+
+## Android
+
+WIP, based on https://github.com/rust-windowing/android-ndk-rs#quick-start-hello-world-crate-on-android
+
+Install the Android NDK and SDK as per https://github.com/rust-windowing/android-ndk-rs#1-install-the-android-ndk-and-sdk
+
+Install Android target
+
+```sh
+rustup target add aarch64-linux-android
+```
+
+Install cargo-apk
+
+```sh
+cargo install cargo-apk
+```
+
+Run the Android app
+
+```sh
+cargo apk run --lib
+```

examples/hello_world/src/lib.rs

@@ -0,0 +1,47 @@
+use eframe::egui;
+
+// Android entry point
+#[cfg_attr(target_os = "android", ndk_glue::main(backtrace = "on"))]
+pub fn main() {
+    run()
+}
+
+pub fn run() {
+    let options = eframe::NativeOptions::default();
+    eframe::run_native(
+        "My egui App",
+        options,
+        Box::new(|_cc| Box::new(MyApp::default())),
+    );
+}
+
+struct MyApp {
+    name: String,
+    age: u32,
+}
+
+impl Default for MyApp {
+    fn default() -> Self {
+        Self {
+            name: "Arthur".to_owned(),
+            age: 42,
+        }
+    }
+}
+
+impl eframe::App for MyApp {
+    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
+        egui::CentralPanel::default().show(ctx, |ui| {
+            ui.heading("My egui Application");
+            ui.horizontal(|ui| {
+                ui.label("Your name: ");
+                ui.text_edit_singleline(&mut self.name);
+            });
+            ui.add(egui::Slider::new(&mut self.age, 0..=120).text("age"));
+            if ui.button("Click each year").clicked() {
+                self.age += 1;
+            }
+            ui.label(format!("Hello '{}', age {}", self.name, self.age));
+        });
+    }
+}

examples/hello_world/src/main.rs

@@ -1,43 +1,6 @@
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
 
-use eframe::egui;
-
+// Linux, MacOS, Windows entry point
 fn main() {
-    let options = eframe::NativeOptions::default();
-    eframe::run_native(
-        "My egui App",
-        options,
-        Box::new(|_cc| Box::new(MyApp::default())),
-    );
-}
-
-struct MyApp {
-    name: String,
-    age: u32,
-}
-
-impl Default for MyApp {
-    fn default() -> Self {
-        Self {
-            name: "Arthur".to_owned(),
-            age: 42,
-        }
-    }
-}
-
-impl eframe::App for MyApp {
-    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
-        egui::CentralPanel::default().show(ctx, |ui| {
-            ui.heading("My egui Application");
-            ui.horizontal(|ui| {
-                ui.label("Your name: ");
-                ui.text_edit_singleline(&mut self.name);
-            });
-            ui.add(egui::Slider::new(&mut self.age, 0..=120).text("age"));
-            if ui.button("Click each year").clicked() {
-                self.age += 1;
-            }
-            ui.label(format!("Hello '{}', age {}", self.name, self.age));
-        });
-    }
+    hello_world::run()
 }