android-activity/examples/agdk-mainloop/src/lib.rs

use android_activity::{AndroidApp, InputStatus, MainEvent, PollEvent};
use log::info;

#[no_mangle]
fn android_main(app: AndroidApp) {
    android_logger::init_once(android_logger::Config::default().with_min_level(log::Level::Info));

    let mut quit = false;
    let mut redraw_pending = true;
    let mut render_state: Option<()> = Default::default();

    while !quit {
        app.poll_events(
            Some(std::time::Duration::from_secs(1)), /* timeout */
            |event| {
                match event {
                    PollEvent::Wake => {
                        info!("Early wake up");
                    }
                    PollEvent::Timeout => {
                        info!("Timed out");
                        // Real app would probably rely on vblank sync via graphics API...
                        redraw_pending = true;
                    }
                    PollEvent::Main(main_event) => {
                        info!("Main event: {:?}", main_event);
                        match main_event {
                            MainEvent::SaveState { saver, .. } => {
                                saver.store("foo://bar".as_bytes());
                            }
                            MainEvent::Pause => {}
                            MainEvent::Resume { loader, .. } => {
                                if let Some(state) = loader.load() {
                                    if let Ok(uri) = String::from_utf8(state) {
                                        info!("Resumed with saved state = {uri:#?}");
                                    }
                                }
                            }
                            MainEvent::InitWindow { .. } => {
                                render_state = Some(());
                                redraw_pending = true;
                            }
                            MainEvent::TerminateWindow { .. } => {
                                render_state = None;
                            }
                            MainEvent::WindowResized { .. } => {
                                redraw_pending = true;
                            }
                            MainEvent::RedrawNeeded { .. } => {
                                redraw_pending = true;
                            }
                            MainEvent::InputAvailable { .. } => {
                                redraw_pending = true;
                            }
                            MainEvent::ConfigChanged { .. } => {
                                info!("Config Changed: {:#?}", app.config());
                            }
                            MainEvent::LowMemory => {}

                            MainEvent::Destroy => quit = true,
                            _ => { /* ... */ }
                        }
                    }
                    _ => {}
                }

                if redraw_pending {
                    if let Some(_rs) = render_state {
                        redraw_pending = false;

                        // Handle input
                        app.input_events(|event| {
                            info!("Input Event: {event:?}");
                            InputStatus::Unhandled
                        });

                        info!("Render...");
                    }
                }
            },
        );
    }
}