android - Sceneform - 如何修复泄漏的 SceneView？

Question

我已经使用 SceneView 加载 3D 模型将近一年了，但我一直不明白是什么导致了这种泄漏。我会实现 LeakCanary，但只有这一次泄漏，因为我不知道如何解决这个问题。

但现在我想弄清问题的根源并尝试解决它。我已经在 Sceneform 的两个版本上对其进行了测试——1.15.0 和被 Google 1.17.1 弃用之前的最后一个版本以及两个问题都会发生。

当您在 Activity 或 Fragment 中使用 SceneView 加载模型时会发生泄漏(我都试过了)并且您“退出”通过执行 System home navigation 或通过 Recent tasks list 切换到不同的应用程序”。

泄漏日志:

┬───
│ GC Root: System class
│
├─ android.app.ActivityThread class
│    Leaking: NO (MainActivity↓ is not leaking and a class is never leaking)
│    ↓ static ActivityThread.sCurrentActivityThread
├─ android.app.ActivityThread instance
│    Leaking: NO (MainActivity↓ is not leaking)
│    mInitialApplication instance of android.app.Application
│    ↓ ActivityThread.mActivities
├─ android.util.ArrayMap instance
│    Leaking: NO (MainActivity↓ is not leaking)
│    ↓ ArrayMap.mArray
├─ java.lang.Object[] array
│    Leaking: NO (MainActivity↓ is not leaking)
│    ↓ Object[].[1]
├─ android.app.ActivityThread$ActivityClientRecord instance
│    Leaking: NO (MainActivity↓ is not leaking)
│    activity instance of com.example.a3dmodeltester.MainActivity with
│    mDestroyed = false
│    ↓ ActivityThread$ActivityClientRecord.activity
├─ com.example.a3dmodeltester.MainActivity instance
│    Leaking: NO (SceneView↓ is not leaking and Activity#mDestroyed is false)
│    mApplication instance of android.app.Application
│    mBase instance of android.app.ContextImpl
│    ↓ MainActivity.sceneView
├─ com.google.ar.sceneform.SceneView instance
│    Leaking: NO (View attached)
│    View is part of a window view hierarchy
│    View.mAttachInfo is not null (view attached)
│    View.mID = R.id.sceneview
│    View.mWindowAttachCount = 1
│    mContext instance of com.example.a3dmodeltester.MainActivity with
│    mDestroyed = false
│    ↓ SceneView.renderer
│                ~~~~~~~~
├─ com.google.ar.sceneform.rendering.Renderer instance
│    Leaking: UNKNOWN
│    Retaining 2.9 kB in 38 objects
│    ↓ Renderer.viewAttachmentManager
│               ~~~~~~~~~~~~~~~~~~~~~
├─ com.google.ar.sceneform.rendering.ViewAttachmentManager instance
│    Leaking: UNKNOWN
│    Retaining 2.2 kB in 19 objects
│    ↓ ViewAttachmentManager.frameLayout
│                            ~~~~~~~~~~~
╰→ android.widget.FrameLayout instance
​     Leaking: YES (ObjectWatcher was watching this because android.widget.
​     FrameLayout received View#onDetachedFromWindow() callback)
​     Retaining 1.9 kB in 15 objects
​     key = 10550463-895e-443a-898f-11c5131da209
​     watchDurationMillis = 5165
​     retainedDurationMillis = 157
​     View not part of a window view hierarchy
​     View.mAttachInfo is null (view detached)
​     View.mWindowAttachCount = 1
​     mContext instance of com.example.a3dmodeltester.MainActivity with
​     mDestroyed = false

METADATA

Build.VERSION.SDK_INT: 27
Build.MANUFACTURER: Google
LeakCanary version: 2.7
App process name: com.example.a3dmodeltester
Stats: LruCache[maxSize=3000,hits=892,misses=24408,hitRate=3%]
RandomAccess[bytes=1232425,reads=24408,travel=6462427001,range=8963521,size=1161
0814]
Heap dump reason: 1 retained objects, app is not visible
Analysis duration: 5411 ms

重现泄漏:

弃用前的最后一个版本:

 implementation 'com.google.ar.sceneform.ux:sceneform-ux:1.17.1'
 debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.7'

我也用 1.15.0 试过了

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    
    <com.google.ar.sceneform.SceneView
        android:id="@+id/sceneview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/white"/>
</RelativeLayout>

MainActivity(也测试了 fragment )

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "MainActivity";

    private static final Vector3   STARTING_CAMERA_POSITION = new Vector3(0f, 1f, 3f);
    private              SceneView sceneView;
    private              Node      node;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        sceneView = findViewById(R.id.sceneview);
        Scene scene = sceneView.getScene();
        node = new Node();
        scene.addChild(node);

        ModelRenderable.builder()
                .setSource(this, Uri.parse("Andy.sfb"))
                .build()
                .thenAccept(renderable -> node.setRenderable(renderable))
                .exceptionally(
                        throwable -> {
                            Log.e(TAG, "Unable to load Renderable.", throwable);
                            return null;
                        });
        Camera camera = scene.getCamera();
        camera.setWorldPosition(STARTING_CAMERA_POSITION);
    }

    @Override
    public void onPause() {
        super.onPause();
        sceneView.pause();
    }

    @Override
    public void onResume() {
        super.onResume();
        try {
            sceneView.resume();
        } catch (CameraNotAvailableException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        sceneView.destroy();
    }
}

.sfb 文件

https://drive.google.com/file/d/1NchJ2NGNM7NZzRZkq4fewALc7m4dnGG3/view?usp=sharing

要重现，请在 SceneView 运行时按 Home 或 Recent task list 按钮

我也仅使用 SceneView 对其进行了测试，但它也会泄漏。

我该如何解决这个漏洞？

我还在多个 API、模拟器和真实设备上对其进行了测试，并且它发生在所有这些设备上。

Answer 1

我已经尝试了这些选项来阻止泄漏，但它们没有做任何事情:

Scene scene = sceneView.getScene();
scene = null;
sceneView = null;
sceneView.destroy();
Renderer.destroyAllResources();
Renderer.reclaimReleasedResources();

然而，这为我修复了漏洞:

从

中删除sceneView.pause();

@Override
public void onPause()

在执行系统主页导航或通过“最近的任务”列表切换到其他应用程序时停止泄漏。 (OP中的问题)

添加 sceneView.pause(); 到

@Override
public void onDestroy()

防止 Activity 或 fragment 被销毁时发生泄漏。

    @Override
    public void onDestroy() {
        super.onDestroy();
        sceneView.pause(); 
    }