Fix bug 2964954 - Lists blow up if their adapter changes while detached.

If a list adapter's content changes while the ListView is detached
from a window, the data change is not registered and the next
layoutChildren call causes the ListView to detect a bad change that
the adapter did not notify ListView about. Any time a ListView becomes
attached to a window, has a valid adapter, and no attached data set
observer, treat it as a data set changed event.

Change-Id: Ic00c05a1a0d063399dc78d5d877e3d5f9b1bee16

1 files changed, 5 insertions, 0 deletions

diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index 740521b..728c2a7 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -1988,6 +1988,11 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
         if (mAdapter != null && mDataSetObserver == null) {
             mDataSetObserver = new AdapterDataSetObserver();
             mAdapter.registerDataSetObserver(mDataSetObserver);
+
+            // Data may have changed while we were detached. Refresh.
+            mDataChanged = true;
+            mOldItemCount = mItemCount;
+            mItemCount = mAdapter.getCount();
         }
     }