commit 7db82acd8151684a886d4725ddf2790ef3a2f80e
author Adam Powell <adamp@google.com> Thu Sep 22 19:44:04 2011 -0700
committer Adam Powell <adamp@google.com> Thu Sep 22 19:55:41 2011 -0700
tree efa891661850f9a2ff5068a25e9f87f70bc26a97
parent e94d950d122005bb10e11dd18b6029d0108f2fbe

Fix leaky view tags

The implementation of the method View#setTag(int, Object) stored tag
objects as entries in a static WeakHashMap associated with the View as
a key. This was problematic for any tag object that stored a hard
reference back to the View the tag was placed on, as it would cause
the WeakReference key to never be collected and the entry to persist
forever.

This was particularly nasty if an app used a keyed tag to store a
ViewHolder object referencing child views for use in the Adapter
implementaion for an AdapterView, since child views will always have
hard references leading back to the parent.

Change-Id: Ia17840a301ba0e0c928861405388fb2f625dac2c

core/java/android/view/View.java

diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index f993160..46cda2d 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -81,7 +81,6 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Locale;
-import java.util.WeakHashMap;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 /**
@@ -1497,12 +1496,7 @@
     /**
      * Map used to store views' tags.
      */
-    private static WeakHashMap<View, SparseArray<Object>> sTags;
-
-    /**
-     * Lock used to access sTags.
-     */
-    private static final Object sTagsLock = new Object();
+    private SparseArray<Object> mKeyedTags;
 
     /**
      * The next available accessiiblity id.
@@ -12236,14 +12230,7 @@
      * @see #getTag()
      */
     public Object getTag(int key) {
-        SparseArray<Object> tags = null;
-        synchronized (sTagsLock) {
-            if (sTags != null) {
-                tags = sTags.get(this);
-            }
-        }
-
-        if (tags != null) return tags.get(key);
+        if (mKeyedTags != null) return mKeyedTags.get(key);
         return null;
     }
 
@@ -12276,7 +12263,7 @@
                     + "resource id.");
         }
 
-        setTagInternal(this, key, tag);
+        setKeyedTag(this, key, tag);
     }
 
     /**
@@ -12291,27 +12278,15 @@
                     + "resource id.");
         }
 
-        setTagInternal(this, key, tag);
+        setKeyedTag(this, key, tag);
     }
 
-    private static void setTagInternal(View view, int key, Object tag) {
-        SparseArray<Object> tags = null;
-        synchronized (sTagsLock) {
-            if (sTags == null) {
-                sTags = new WeakHashMap<View, SparseArray<Object>>();
-            } else {
-                tags = sTags.get(view);
-            }
+    private void setKeyedTag(View view, int key, Object tag) {
+        if (mKeyedTags == null) {
+            mKeyedTags = new SparseArray<Object>();
         }
 
-        if (tags == null) {
-            tags = new SparseArray<Object>(2);
-            synchronized (sTagsLock) {
-                sTags.put(view, tags);
-            }
-        }
-
-        tags.put(key, tag);
+        mKeyedTags.put(key, tag);
     }
 
     /**