Update na-mainloop

examples/na-mainloop/Cargo.toml

@@ -9,6 +9,8 @@ edition = "2021"
 log = "0.4"
 android_logger = "0.11.0"
 android-activity = { path="../../android-activity", features = [ "native-activity" ] }
+ndk-sys = "0.4"
+ndk = "0.7"
 
 [lib]
 #name="na_mainloop"

examples/na-mainloop/app/build.gradle

@@ -3,6 +3,7 @@ plugins {
 }
 
 android {
+    ndkVersion "25.2.9519653"
     compileSdk 31
 
     defaultConfig {
@@ -32,6 +33,7 @@ android {
         sourceCompatibility JavaVersion.VERSION_1_8
         targetCompatibility JavaVersion.VERSION_1_8
     }
+    namespace 'co.realfit.namainloop'
 }
 
 dependencies {

examples/na-mainloop/app/src/main/AndroidManifest.xml

@@ -1,6 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="co.realfit.namainloop">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <application
         android:allowBackup="true"

examples/na-mainloop/build.gradle

@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
-    id 'com.android.application' version '7.1.2' apply false
-    id 'com.android.library' version '7.1.2' apply false
+    id 'com.android.application' version '8.0.0' apply false
+    id 'com.android.library' version '8.0.0' apply false
 }
 
 task clean(type: Delete) {

examples/na-mainloop/gradle.properties

@@ -18,4 +18,6 @@ android.useAndroidX=true
 # Enables namespacing of each library's R class so that its R class includes only the
 # resources declared in the library itself and none from the library's dependencies,
 # thereby reducing the size of the R class for that library
-android.nonTransitiveRClass=true
+android.nonTransitiveRClass=true
+android.defaults.buildfeatures.buildconfig=true
+android.nonFinalResIds=false

examples/na-mainloop/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Mon May 02 15:39:12 BST 2022
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.5-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME

examples/na-mainloop/src/lib.rs

@@ -7,7 +7,7 @@ fn android_main(app: AndroidApp) {
 
     let mut quit = false;
     let mut redraw_pending = true;
-    let mut render_state: Option<()> = Default::default();
+    let mut native_window: Option<ndk::native_window::NativeWindow> = None;
 
     while !quit {
         app.poll_events(
@@ -37,11 +37,11 @@ fn android_main(app: AndroidApp) {
                                 }
                             }
                             MainEvent::InitWindow { .. } => {
-                                render_state = Some(());
+                                native_window = app.native_window();
                                 redraw_pending = true;
                             }
                             MainEvent::TerminateWindow { .. } => {
-                                render_state = None;
+                                native_window = None;
                             }
                             MainEvent::WindowResized { .. } => {
                                 redraw_pending = true;
@@ -65,7 +65,7 @@ fn android_main(app: AndroidApp) {
                 }
 
                 if redraw_pending {
-                    if let Some(_rs) = render_state {
+                    if let Some(native_window) = &native_window {
                         redraw_pending = false;
 
                         // Handle input
@@ -75,9 +75,32 @@ fn android_main(app: AndroidApp) {
                         });
 
                         info!("Render...");
+                        dummy_render(native_window);
                     }
                 }
             },
         );
     }
 }
+
+/// Post a NOP frame to the window
+///
+/// Since this is a bare minimum test app we don't depend
+/// on any GPU graphics APIs but we do need to at least
+/// convince Android that we're drawing something and are
+/// responsive, otherwise it will stop delivering input
+/// events to us.
+fn dummy_render(native_window: &ndk::native_window::NativeWindow) {
+    unsafe {
+        let mut buf: ndk_sys::ANativeWindow_Buffer = std::mem::zeroed();
+        let mut rect: ndk_sys::ARect = std::mem::zeroed();
+        ndk_sys::ANativeWindow_lock(
+            native_window.ptr().as_ptr() as _,
+            &mut buf as _,
+            &mut rect as _,
+        );
+        // Note: we don't try and touch the buffer since that
+        // also requires us to handle various buffer formats
+        ndk_sys::ANativeWindow_unlockAndPost(native_window.ptr().as_ptr() as _);
+    }
+}