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diff --git a/java/com/android/contacts/common/list/IndexerListAdapter.java b/java/com/android/contacts/common/list/IndexerListAdapter.java
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+++ b/java/com/android/contacts/common/list/IndexerListAdapter.java
@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2010 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 com.android.contacts.common.list;
+
+import android.content.Context;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ListView;
+import android.widget.SectionIndexer;
+
+/** A list adapter that supports section indexer and a pinned header. */
+public abstract class IndexerListAdapter extends PinnedHeaderListAdapter implements SectionIndexer {
+
+  protected Context mContext;
+  private SectionIndexer mIndexer;
+  private int mIndexedPartition = 0;
+  private boolean mSectionHeaderDisplayEnabled;
+  private View mHeader;
+  private Placement mPlacementCache = new Placement();
+
+  /** Constructor. */
+  public IndexerListAdapter(Context context) {
+    super(context);
+    mContext = context;
+  }
+
+  /**
+   * Creates a section header view that will be pinned at the top of the list as the user scrolls.
+   */
+  protected abstract View createPinnedSectionHeaderView(Context context, ViewGroup parent);
+
+  /** Sets the title in the pinned header as the user scrolls. */
+  protected abstract void setPinnedSectionTitle(View pinnedHeaderView, String title);
+
+  public boolean isSectionHeaderDisplayEnabled() {
+    return mSectionHeaderDisplayEnabled;
+  }
+
+  public void setSectionHeaderDisplayEnabled(boolean flag) {
+    this.mSectionHeaderDisplayEnabled = flag;
+  }
+
+  public int getIndexedPartition() {
+    return mIndexedPartition;
+  }
+
+  public void setIndexedPartition(int partition) {
+    this.mIndexedPartition = partition;
+  }
+
+  public SectionIndexer getIndexer() {
+    return mIndexer;
+  }
+
+  public void setIndexer(SectionIndexer indexer) {
+    mIndexer = indexer;
+    mPlacementCache.invalidate();
+  }
+
+  public Object[] getSections() {
+    if (mIndexer == null) {
+      return new String[] {" "};
+    } else {
+      return mIndexer.getSections();
+    }
+  }
+
+  /** @return relative position of the section in the indexed partition */
+  public int getPositionForSection(int sectionIndex) {
+    if (mIndexer == null) {
+      return -1;
+    }
+
+    return mIndexer.getPositionForSection(sectionIndex);
+  }
+
+  /** @param position relative position in the indexed partition */
+  public int getSectionForPosition(int position) {
+    if (mIndexer == null) {
+      return -1;
+    }
+
+    return mIndexer.getSectionForPosition(position);
+  }
+
+  @Override
+  public int getPinnedHeaderCount() {
+    if (isSectionHeaderDisplayEnabled()) {
+      return super.getPinnedHeaderCount() + 1;
+    } else {
+      return super.getPinnedHeaderCount();
+    }
+  }
+
+  @Override
+  public View getPinnedHeaderView(int viewIndex, View convertView, ViewGroup parent) {
+    if (isSectionHeaderDisplayEnabled() && viewIndex == getPinnedHeaderCount() - 1) {
+      if (mHeader == null) {
+        mHeader = createPinnedSectionHeaderView(mContext, parent);
+      }
+      return mHeader;
+    } else {
+      return super.getPinnedHeaderView(viewIndex, convertView, parent);
+    }
+  }
+
+  @Override
+  public void configurePinnedHeaders(PinnedHeaderListView listView) {
+    super.configurePinnedHeaders(listView);
+
+    if (!isSectionHeaderDisplayEnabled()) {
+      return;
+    }
+
+    int index = getPinnedHeaderCount() - 1;
+    if (mIndexer == null || getCount() == 0) {
+      listView.setHeaderInvisible(index, false);
+    } else {
+      int listPosition = listView.getPositionAt(listView.getTotalTopPinnedHeaderHeight());
+      int position = listPosition - listView.getHeaderViewsCount();
+
+      int section = -1;
+      int partition = getPartitionForPosition(position);
+      if (partition == mIndexedPartition) {
+        int offset = getOffsetInPartition(position);
+        if (offset != -1) {
+          section = getSectionForPosition(offset);
+        }
+      }
+
+      if (section == -1) {
+        listView.setHeaderInvisible(index, false);
+      } else {
+        View topChild = listView.getChildAt(listPosition);
+        if (topChild != null) {
+          // Match the pinned header's height to the height of the list item.
+          mHeader.setMinimumHeight(topChild.getMeasuredHeight());
+        }
+        setPinnedSectionTitle(mHeader, (String) mIndexer.getSections()[section]);
+
+        // Compute the item position where the current partition begins
+        int partitionStart = getPositionForPartition(mIndexedPartition);
+        if (hasHeader(mIndexedPartition)) {
+          partitionStart++;
+        }
+
+        // Compute the item position where the next section begins
+        int nextSectionPosition = partitionStart + getPositionForSection(section + 1);
+        boolean isLastInSection = position == nextSectionPosition - 1;
+        listView.setFadingHeader(index, listPosition, isLastInSection);
+      }
+    }
+  }
+
+  /**
+   * Computes the item's placement within its section and populates the {@code placement} object
+   * accordingly. Please note that the returned object is volatile and should be copied if the
+   * result needs to be used later.
+   */
+  public Placement getItemPlacementInSection(int position) {
+    if (mPlacementCache.position == position) {
+      return mPlacementCache;
+    }
+
+    mPlacementCache.position = position;
+    if (isSectionHeaderDisplayEnabled()) {
+      int section = getSectionForPosition(position);
+      if (section != -1 && getPositionForSection(section) == position) {
+        mPlacementCache.firstInSection = true;
+        mPlacementCache.sectionHeader = (String) getSections()[section];
+      } else {
+        mPlacementCache.firstInSection = false;
+        mPlacementCache.sectionHeader = null;
+      }
+
+      mPlacementCache.lastInSection = (getPositionForSection(section + 1) - 1 == position);
+    } else {
+      mPlacementCache.firstInSection = false;
+      mPlacementCache.lastInSection = false;
+      mPlacementCache.sectionHeader = null;
+    }
+    return mPlacementCache;
+  }
+
+  /**
+   * An item view is displayed differently depending on whether it is placed at the beginning,
+   * middle or end of a section. It also needs to know the section header when it is at the
+   * beginning of a section. This object captures all this configuration.
+   */
+  public static final class Placement {
+
+    public boolean firstInSection;
+    public boolean lastInSection;
+    public String sectionHeader;
+    private int position = ListView.INVALID_POSITION;
+
+    public void invalidate() {
+      position = ListView.INVALID_POSITION;
+    }
+  }
+}