Merge "AccessibilityNodeIdManager should hold onto weak references of Views." into qt-dev

core/java/android/view/accessibility/AccessibilityNodeIdManager.java

@@ -16,12 +16,11 @@
 
 package android.view.accessibility;
 
-import android.util.SparseArray;
 import android.view.View;
 
 /** @hide */
 public final class AccessibilityNodeIdManager {
-    private SparseArray<View> mIdsToViews = new SparseArray<>();
+    private WeakSparseArray<View> mIdsToViews = new WeakSparseArray<View>();
     private static AccessibilityNodeIdManager sIdManager;
 
     /**

core/java/android/view/accessibility/WeakSparseArray.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.view.accessibility;
+
+import android.util.SparseArray;
+
+import java.lang.ref.Reference;
+import java.lang.ref.ReferenceQueue;
+import java.lang.ref.WeakReference;
+
+
+final class WeakSparseArray<E> {
+
+    private final ReferenceQueue<E> mRefQueue = new ReferenceQueue<>();
+    private final SparseArray<WeakReferenceWithId<E>> mSparseArray = new SparseArray<>();
+
+    public void append(int key, E value) {
+        removeUnreachableValues();
+        mSparseArray.append(key, new WeakReferenceWithId(value, mRefQueue, key));
+    }
+
+    public void remove(int key) {
+        removeUnreachableValues();
+        mSparseArray.remove(key);
+    }
+
+    public E get(int key) {
+        removeUnreachableValues();
+        WeakReferenceWithId<E> ref = mSparseArray.get(key);
+        return ref != null ? ref.get() : null;
+    }
+
+    private void removeUnreachableValues() {
+        for (Reference ref = mRefQueue.poll(); ref != null; ref = mRefQueue.poll()) {
+            mSparseArray.remove(((WeakReferenceWithId) ref).mId);
+        }
+    }
+
+    private static class WeakReferenceWithId<E> extends WeakReference<E> {
+
+        final int mId;
+
+        WeakReferenceWithId(E referent, ReferenceQueue<? super E> q, int id) {
+            super(referent, q);
+            mId = id;
+        }
+    }
+}
+