Fix the SurfaceTexture related crash by Replacing the JNI weak global reference with a WeakReference<SurfaceTexture>

Author: ColdPaleLight

shell/platform/android/android_external_texture_gl.cc

@@ -13,7 +13,7 @@ namespace flutter {
 
 AndroidExternalTextureGL::AndroidExternalTextureGL(
     int64_t id,
-    const fml::jni::JavaObjectWeakGlobalRef& surface_texture,
+    const fml::jni::ScopedJavaGlobalRef<jobject>& surface_texture,
     std::shared_ptr<PlatformViewAndroidJNI> jni_facade)
     : Texture(id),
       jni_facade_(jni_facade),
@@ -74,7 +74,8 @@ void AndroidExternalTextureGL::Paint(SkCanvas& canvas,
 }
 
 void AndroidExternalTextureGL::UpdateTransform() {
-  jni_facade_->SurfaceTextureGetTransformMatrix(surface_texture_, transform);
+  jni_facade_->SurfaceTextureGetTransformMatrix(
+      fml::jni::ScopedJavaLocalRef<jobject>(surface_texture_), transform);
 }
 
 void AndroidExternalTextureGL::OnGrContextDestroyed() {
@@ -86,16 +87,19 @@ void AndroidExternalTextureGL::OnGrContextDestroyed() {
 }
 
 void AndroidExternalTextureGL::Attach(jint textureName) {
-  jni_facade_->SurfaceTextureAttachToGLContext(surface_texture_, textureName);
+  jni_facade_->SurfaceTextureAttachToGLContext(
+      fml::jni::ScopedJavaLocalRef<jobject>(surface_texture_), textureName);
 }
 
 void AndroidExternalTextureGL::Update() {
-  jni_facade_->SurfaceTextureUpdateTexImage(surface_texture_);
+  jni_facade_->SurfaceTextureUpdateTexImage(
+      fml::jni::ScopedJavaLocalRef<jobject>(surface_texture_));
   UpdateTransform();
 }
 
 void AndroidExternalTextureGL::Detach() {
-  jni_facade_->SurfaceTextureDetachFromGLContext(surface_texture_);
+  jni_facade_->SurfaceTextureDetachFromGLContext(
+      fml::jni::ScopedJavaLocalRef<jobject>(surface_texture_));
 }
 
 void AndroidExternalTextureGL::OnTextureUnregistered() {}

shell/platform/android/android_external_texture_gl.h

@@ -8,7 +8,6 @@
 #include <GLES/gl.h>
 
 #include "flutter/common/graphics/texture.h"
-#include "flutter/fml/platform/android/jni_weak_ref.h"
 #include "flutter/shell/platform/android/platform_view_android_jni_impl.h"
 
 namespace flutter {
@@ -17,7 +16,7 @@ class AndroidExternalTextureGL : public flutter::Texture {
  public:
   AndroidExternalTextureGL(
       int64_t id,
-      const fml::jni::JavaObjectWeakGlobalRef& surface_texture,
+      const fml::jni::ScopedJavaGlobalRef<jobject>& surface_texture,
       std::shared_ptr<PlatformViewAndroidJNI> jni_facade);
 
   ~AndroidExternalTextureGL() override;
@@ -49,7 +48,7 @@ class AndroidExternalTextureGL : public flutter::Texture {
 
   std::shared_ptr<PlatformViewAndroidJNI> jni_facade_;
 
-  fml::jni::JavaObjectWeakGlobalRef surface_texture_;
+  fml::jni::ScopedJavaGlobalRef<jobject> surface_texture_;
 
   AttachmentState state_ = AttachmentState::uninitialized;
 

shell/platform/android/io/flutter/embedding/engine/FlutterJNI.java

@@ -34,6 +34,7 @@
 import io.flutter.view.AccessibilityBridge;
 import io.flutter.view.FlutterCallbackInformation;
 import java.io.IOException;
+import java.lang.ref.WeakReference;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.List;
@@ -756,11 +757,14 @@ public void setAccessibilityFeatures(int flags) {
   public void registerTexture(long textureId, @NonNull SurfaceTextureWrapper textureWrapper) {
     ensureRunningOnMainThread();
     ensureAttachedToNative();
-    nativeRegisterTexture(nativeShellHolderId, textureId, textureWrapper);
+    nativeRegisterTexture(
+        nativeShellHolderId, textureId, new WeakReference<SurfaceTextureWrapper>(textureWrapper));
   }
 
   private native void nativeRegisterTexture(
-      long nativeShellHolderId, long textureId, @NonNull SurfaceTextureWrapper textureWrapper);
+      long nativeShellHolderId,
+      long textureId,
+      @NonNull WeakReference<SurfaceTextureWrapper> textureWrapper);
 
   /**
    * Call this method to inform Flutter that a texture previously registered with {@link

shell/platform/android/jni/jni_mock.h

@@ -46,22 +46,22 @@ class JNIMock final : public PlatformViewAndroidJNI {
 
   MOCK_METHOD(void,
               SurfaceTextureAttachToGLContext,
-              (JavaWeakGlobalRef surface_texture, int textureId),
+              (JavaLocalRef surface_texture, int textureId),
               (override));
 
   MOCK_METHOD(void,
               SurfaceTextureUpdateTexImage,
-              (JavaWeakGlobalRef surface_texture),
+              (JavaLocalRef surface_texture),
               (override));
 
   MOCK_METHOD(void,
               SurfaceTextureGetTransformMatrix,
-              (JavaWeakGlobalRef surface_texture, SkMatrix& transform),
+              (JavaLocalRef surface_texture, SkMatrix& transform),
               (override));
 
   MOCK_METHOD(void,
               SurfaceTextureDetachFromGLContext,
-              (JavaWeakGlobalRef surface_texture),
+              (JavaLocalRef surface_texture),
               (override));
 
   MOCK_METHOD(void,

shell/platform/android/jni/platform_view_android_jni.h

@@ -14,15 +14,15 @@
 #include "third_party/skia/include/core/SkMatrix.h"
 
 #if OS_ANDROID
-#include "flutter/fml/platform/android/jni_weak_ref.h"
+#include "flutter/fml/platform/android/scoped_java_ref.h"
 #endif
 
 namespace flutter {
 
 #if OS_ANDROID
-using JavaWeakGlobalRef = fml::jni::JavaObjectWeakGlobalRef;
+using JavaLocalRef = fml::jni::ScopedJavaLocalRef<jobject>;
 #else
-using JavaWeakGlobalRef = std::nullptr_t;
+using JavaLocalRef = std::nullptr_t;
 #endif
 
 //------------------------------------------------------------------------------
@@ -86,31 +86,28 @@ class PlatformViewAndroidJNI {
   /// @brief      Attach the SurfaceTexture to the OpenGL ES context that is
   ///             current on the calling thread.
   ///
-  virtual void SurfaceTextureAttachToGLContext(
-      JavaWeakGlobalRef surface_texture,
-      int textureId) = 0;
+  virtual void SurfaceTextureAttachToGLContext(JavaLocalRef surface_texture,
+                                               int textureId) = 0;
 
   //----------------------------------------------------------------------------
   /// @brief      Updates the texture image to the most recent frame from the
   ///             image stream.
   ///
-  virtual void SurfaceTextureUpdateTexImage(
-      JavaWeakGlobalRef surface_texture) = 0;
+  virtual void SurfaceTextureUpdateTexImage(JavaLocalRef surface_texture) = 0;
 
   //----------------------------------------------------------------------------
   /// @brief      Gets the transform matrix from the SurfaceTexture.
   ///             Then, it updates the `transform` matrix, so it fill the canvas
   ///             and preserve the aspect ratio.
   ///
-  virtual void SurfaceTextureGetTransformMatrix(
-      JavaWeakGlobalRef surface_texture,
-      SkMatrix& transform) = 0;
+  virtual void SurfaceTextureGetTransformMatrix(JavaLocalRef surface_texture,
+                                                SkMatrix& transform) = 0;
 
   //----------------------------------------------------------------------------
   /// @brief      Detaches a SurfaceTexture from the OpenGL ES context.
   ///
   virtual void SurfaceTextureDetachFromGLContext(
-      JavaWeakGlobalRef surface_texture) = 0;
+      JavaLocalRef surface_texture) = 0;
 
   //----------------------------------------------------------------------------
   /// @brief      Positions and sizes a platform view if using hybrid

shell/platform/android/platform_view_android.cc

@@ -291,7 +291,7 @@ void PlatformViewAndroid::UpdateSemantics(
 
 void PlatformViewAndroid::RegisterExternalTexture(
     int64_t texture_id,
-    const fml::jni::JavaObjectWeakGlobalRef& surface_texture) {
+    const fml::jni::ScopedJavaGlobalRef<jobject>& surface_texture) {
   RegisterTexture(std::make_shared<AndroidExternalTextureGL>(
       texture_id, surface_texture, std::move(jni_facade_)));
 }

shell/platform/android/platform_view_android.h

@@ -11,7 +11,6 @@
 #include <vector>
 
 #include "flutter/fml/memory/weak_ptr.h"
-#include "flutter/fml/platform/android/jni_weak_ref.h"
 #include "flutter/fml/platform/android/scoped_java_ref.h"
 #include "flutter/lib/ui/window/platform_message.h"
 #include "flutter/shell/common/platform_view.h"
@@ -97,7 +96,7 @@ class PlatformViewAndroid final : public PlatformView {
 
   void RegisterExternalTexture(
       int64_t texture_id,
-      const fml::jni::JavaObjectWeakGlobalRef& surface_texture);
+      const fml::jni::ScopedJavaGlobalRef<jobject>& surface_texture);
 
   // |PlatformView|
   void LoadDartDeferredLibrary(

shell/platform/android/platform_view_android_jni_impl.cc

@@ -42,6 +42,9 @@ static fml::jni::ScopedJavaGlobalRef<jclass>* g_flutter_callback_info_class =
 
 static fml::jni::ScopedJavaGlobalRef<jclass>* g_flutter_jni_class = nullptr;
 
+static fml::jni::ScopedJavaGlobalRef<jclass>* g_java_weak_reference_class =
+    nullptr;
+
 static fml::jni::ScopedJavaGlobalRef<jclass>* g_texture_wrapper_class = nullptr;
 
 static fml::jni::ScopedJavaGlobalRef<jclass>* g_java_long_class = nullptr;
@@ -87,6 +90,8 @@ static jmethodID g_on_begin_frame_method = nullptr;
 
 static jmethodID g_on_end_frame_method = nullptr;
 
+static jmethodID g_java_weak_reference_get_method = nullptr;
+
 static jmethodID g_attach_to_gl_context_method = nullptr;
 
 static jmethodID g_update_tex_image_method = nullptr;
@@ -452,8 +457,8 @@ static void RegisterTexture(JNIEnv* env,
                             jlong texture_id,
                             jobject surface_texture) {
   ANDROID_SHELL_HOLDER->GetPlatformView()->RegisterExternalTexture(
-      static_cast<int64_t>(texture_id),                        //
-      fml::jni::JavaObjectWeakGlobalRef(env, surface_texture)  //
+      static_cast<int64_t>(texture_id),                             //
+      fml::jni::ScopedJavaGlobalRef<jobject>(env, surface_texture)  //
   );
 }
 
@@ -714,8 +719,8 @@ bool RegisterApi(JNIEnv* env) {
       },
       {
           .name = "nativeRegisterTexture",
-          .signature = "(JJLio/flutter/embedding/engine/renderer/"
-                       "SurfaceTextureWrapper;)V",
+          .signature = "(JJLjava/lang/ref/"
+                       "WeakReference;)V",
           .fnPtr = reinterpret_cast<void*>(&RegisterTexture),
       },
       {
@@ -1007,6 +1012,20 @@ bool PlatformViewAndroid::Register(JNIEnv* env) {
     return false;
   }
 
+  g_java_weak_reference_class = new fml::jni::ScopedJavaGlobalRef<jclass>(
+      env, env->FindClass("java/lang/ref/WeakReference"));
+  if (g_java_weak_reference_class->is_null()) {
+    FML_LOG(ERROR) << "Could not locate WeakReference class";
+    return false;
+  }
+
+  g_java_weak_reference_get_method = env->GetMethodID(
+      g_java_weak_reference_class->obj(), "get", "()Ljava/lang/Object;");
+  if (g_java_weak_reference_get_method == nullptr) {
+    FML_LOG(ERROR) << "Could not locate WeakReference.get method";
+    return false;
+  }
+
   g_texture_wrapper_class = new fml::jni::ScopedJavaGlobalRef<jclass>(
       env, env->FindClass(
                "io/flutter/embedding/engine/renderer/SurfaceTextureWrapper"));
@@ -1215,12 +1234,18 @@ void PlatformViewAndroidJNIImpl::FlutterViewOnPreEngineRestart() {
 }
 
 void PlatformViewAndroidJNIImpl::SurfaceTextureAttachToGLContext(
-    JavaWeakGlobalRef surface_texture,
+    JavaLocalRef surface_texture,
     int textureId) {
   JNIEnv* env = fml::jni::AttachCurrentThread();
 
-  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref =
-      surface_texture.get(env);
+  if (surface_texture.is_null()) {
+    return;
+  }
+
+  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref(
+      env, env->CallObjectMethod(surface_texture.obj(),
+                                 g_java_weak_reference_get_method));
+
   if (surface_texture_local_ref.is_null()) {
     return;
   }
@@ -1232,11 +1257,16 @@ void PlatformViewAndroidJNIImpl::SurfaceTextureAttachToGLContext(
 }
 
 void PlatformViewAndroidJNIImpl::SurfaceTextureUpdateTexImage(
-    JavaWeakGlobalRef surface_texture) {
+    JavaLocalRef surface_texture) {
   JNIEnv* env = fml::jni::AttachCurrentThread();
 
-  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref =
-      surface_texture.get(env);
+  if (surface_texture.is_null()) {
+    return;
+  }
+
+  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref(
+      env, env->CallObjectMethod(surface_texture.obj(),
+                                 g_java_weak_reference_get_method));
   if (surface_texture_local_ref.is_null()) {
     return;
   }
@@ -1260,12 +1290,17 @@ SkSize ScaleToFill(float scaleX, float scaleY) {
 }
 
 void PlatformViewAndroidJNIImpl::SurfaceTextureGetTransformMatrix(
-    JavaWeakGlobalRef surface_texture,
+    JavaLocalRef surface_texture,
     SkMatrix& transform) {
   JNIEnv* env = fml::jni::AttachCurrentThread();
 
-  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref =
-      surface_texture.get(env);
+  if (surface_texture.is_null()) {
+    return;
+  }
+
+  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref(
+      env, env->CallObjectMethod(surface_texture.obj(),
+                                 g_java_weak_reference_get_method));
   if (surface_texture_local_ref.is_null()) {
     return;
   }
@@ -1290,11 +1325,16 @@ void PlatformViewAndroidJNIImpl::SurfaceTextureGetTransformMatrix(
 }
 
 void PlatformViewAndroidJNIImpl::SurfaceTextureDetachFromGLContext(
-    JavaWeakGlobalRef surface_texture) {
+    JavaLocalRef surface_texture) {
   JNIEnv* env = fml::jni::AttachCurrentThread();
 
-  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref =
-      surface_texture.get(env);
+  if (surface_texture.is_null()) {
+    return;
+  }
+
+  fml::jni::ScopedJavaLocalRef<jobject> surface_texture_local_ref(
+      env, env->CallObjectMethod(surface_texture.obj(),
+                                 g_java_weak_reference_get_method));
   if (surface_texture_local_ref.is_null()) {
     return;
   }

shell/platform/android/platform_view_android_jni_impl.h

@@ -41,16 +41,15 @@ class PlatformViewAndroidJNIImpl final : public PlatformViewAndroidJNI {
 
   void FlutterViewOnPreEngineRestart() override;
 
-  void SurfaceTextureAttachToGLContext(JavaWeakGlobalRef surface_texture,
+  void SurfaceTextureAttachToGLContext(JavaLocalRef surface_texture,
                                        int textureId) override;
 
-  void SurfaceTextureUpdateTexImage(JavaWeakGlobalRef surface_texture) override;
+  void SurfaceTextureUpdateTexImage(JavaLocalRef surface_texture) override;
 
-  void SurfaceTextureGetTransformMatrix(JavaWeakGlobalRef surface_texture,
+  void SurfaceTextureGetTransformMatrix(JavaLocalRef surface_texture,
                                         SkMatrix& transform) override;
 
-  void SurfaceTextureDetachFromGLContext(
-      JavaWeakGlobalRef surface_texture) override;
+  void SurfaceTextureDetachFromGLContext(JavaLocalRef surface_texture) override;
 
   void FlutterViewOnDisplayPlatformView(int view_id,
                                         int x,