add JNI_OnLoad to Android library. This is needed to manually call ::filament::backend::VirtualMachineEnv::JNI_OnLoad

thermion_flutter/thermion_flutter/android/src/main/cpp/ThermionFlutterAndroid.cpp

@@ -1,16 +1,68 @@
-#include <android/native_window_jni.h>
+#include <android/log.h>
 #include <android/native_activity.h>
+#include <android/native_window_jni.h>
 #include <jni.h>
 
+#include <dlfcn.h>
+#include <android/log.h>
+
+typedef void (*JNI_OnLoad_Func)(JavaVM*);
+
 extern "C" {
-    JNIEXPORT jlong JNICALL Java_dev_thermion_android_NativeWindowHelper_00024Companion_getNativeWindowFromSurface(
+JNIEXPORT jlong JNICALL
-        JNIEnv* env, 
+Java_dev_thermion_android_NativeWindowHelper_00024Companion_getNativeWindowFromSurface(
-        jclass clazz, 
+    JNIEnv *env, jclass clazz, jobject surface) {
-        jobject surface
+  ANativeWindow *window = ANativeWindow_fromSurface(env, surface);
-    ) {
-        ANativeWindow* window = ANativeWindow_fromSurface(env, surface);
   return (jlong)window;
-    }
 }
 
+JNIEXPORT jint JNI_OnLoad(JavaVM *vm, void *reserved) {
 
+     void* filamentLib = dlopen("libthermion_dart.so", RTLD_NOW);
+     if (!filamentLib) {
+         __android_log_print(ANDROID_LOG_ERROR, "thermion_android", 
+                            "Failed to load Filament library: %s", dlerror());
+         return false;
+     }
+     
+     dlerror();
+     
+     JNI_OnLoad_Func vmEnvOnLoad = (JNI_OnLoad_Func)dlsym(filamentLib, 
+                                   "_ZN8filament17VirtualMachineEnv10JNI_OnLoadEP7_JavaVM");
+     
+     // Check for errors
+     const char* dlsym_error = dlerror();
+     if (dlsym_error) {
+         __android_log_print(ANDROID_LOG_ERROR, "thermion_android", 
+                            "Failed to find VirtualMachineEnv::JNI_OnLoad: %s", dlsym_error);
+         dlclose(filamentLib);
+         return false;
+     }
+     
+     // Call the function
+     vmEnvOnLoad(vm);
+     
+    
+  JNIEnv *env;
+  if (vm->GetEnv(reinterpret_cast<void **>(&env), JNI_VERSION_1_6) != JNI_OK) {
+    return JNI_ERR;
+  }
+
+  jclass c =
+      env->FindClass("dev/thermion/android/NativeWindowHelper$Companion");
+  if (c == nullptr)
+    return JNI_ERR;
+
+  static const JNINativeMethod methods[] = {
+      {"getNativeWindowFromSurface", "(Landroid/view/Surface;)J",
+       reinterpret_cast<void *>(
+           Java_dev_thermion_android_NativeWindowHelper_00024Companion_getNativeWindowFromSurface)},
+  };
+  int rc = env->RegisterNatives(c, methods,
+                                sizeof(methods) / sizeof(JNINativeMethod));
+  if (rc != JNI_OK)
+    return rc;
+
+  return JNI_VERSION_1_6;
+}
+}

thermion_flutter/thermion_flutter/android/src/main/kotlin/dev/thermion/android/ThermionFlutterPlugin.kt

@@ -25,9 +25,6 @@ import java.util.*
 
 class NativeWindowHelper {
     companion object {
-      init {
-        System.loadLibrary("thermion_flutter_android")
-      }
       external fun getNativeWindowFromSurface(surface: Surface): Long
     }
 }
@@ -62,6 +59,9 @@ class ThermionFlutterPlugin: FlutterPlugin, MethodCallHandler, ActivityAware {
     this.flutterPluginBinding = flutterPluginBinding
     channel = MethodChannel(flutterPluginBinding.binaryMessenger, CHANNEL_NAME)
     channel.setMethodCallHandler(this)
+    Log.d("thermion_flutter", "Loading library")
+    System.loadLibrary("thermion_flutter_android")
+    Log.d("thermion_flutter", "Loaded")
   }
 
   override fun onAttachedToActivity(binding: ActivityPluginBinding) {
@@ -81,7 +81,7 @@ class ThermionFlutterPlugin: FlutterPlugin, MethodCallHandler, ActivityAware {
                     result.error("DIMENSION_MISMATCH", "Both dimensions must be greater than zero (you provided $width x $height)", null)
                     return
                 }
-                Log.i("thermion_flutter", "Creating SurfaceTexture ${width}x${height}")
+                Log.d("thermion_flutter", "Creating SurfaceTexture ${width}x${height}")
                 
                 val surfaceTextureEntry = flutterPluginBinding.textureRegistry.createSurfaceTexture()
                 val surfaceTexture = surfaceTextureEntry.surfaceTexture()
@@ -95,6 +95,8 @@ class ThermionFlutterPlugin: FlutterPlugin, MethodCallHandler, ActivityAware {
                     val flutterTextureId = surfaceTextureEntry.id()   
                     textures[flutterTextureId] = TextureEntry(surfaceTextureEntry, surfaceTexture, surface)
                     //val surface = surfaceView.holder.surface
+                    Log.d("thermion_flutter", "Loading library")
+                    System.loadLibrary("thermion_flutter_android")
                     val nativeWindowPtr = NativeWindowHelper.getNativeWindowFromSurface(surface)
                     //val nativeWindow = _lib.get_native_window_from_surface(surface as Object, JNIEnv.CURRENT)
                     result.success(listOf(flutterTextureId, flutterTextureId, nativeWindowPtr))