diff --git a/api/current.txt b/api/current.txt
index 5a3c7db..2a81469 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -8051,6 +8051,7 @@
 
   public class MatrixCursor.RowBuilder {
     method public android.database.MatrixCursor.RowBuilder add(java.lang.Object);
+    method public android.database.MatrixCursor.RowBuilder offer(java.lang.String, java.lang.Object);
   }
 
   public class MergeCursor extends android.database.AbstractCursor {
diff --git a/core/java/android/database/MatrixCursor.java b/core/java/android/database/MatrixCursor.java
index 6e68b6b..2a0d9b9 100644
--- a/core/java/android/database/MatrixCursor.java
+++ b/core/java/android/database/MatrixCursor.java
@@ -83,11 +83,10 @@
      *  row
      */
     public RowBuilder newRow() {
-        rowCount++;
-        int endIndex = rowCount * columnCount;
+        final int row = rowCount++;
+        final int endIndex = rowCount * columnCount;
         ensureCapacity(endIndex);
-        int start = endIndex - columnCount;
-        return new RowBuilder(start, endIndex);
+        return new RowBuilder(row);
     }
 
     /**
@@ -180,18 +179,29 @@
     }
 
     /**
-     * Builds a row, starting from the left-most column and adding one column
-     * value at a time. Follows the same ordering as the column names specified
-     * at cursor construction time.
+     * Builds a row of values using either of these approaches:
+     * <ul>
+     * <li>Values can be added with explicit column ordering using
+     * {@link #add(Object)}, which starts from the left-most column and adds one
+     * column value at a time. This follows the same ordering as the column
+     * names specified at cursor construction time.
+     * <li>Column and value pairs can be offered for possible inclusion using
+     * {@link #offer(String, Object)}. If the cursor includes the given column,
+     * the value will be set for that column, otherwise the value is ignored.
+     * This approach is useful when matching data to a custom projection.
+     * </ul>
+     * Undefined values are left as {@code null}.
      */
     public class RowBuilder {
-
-        private int index;
+        private final int row;
         private final int endIndex;
 
-        RowBuilder(int index, int endIndex) {
-            this.index = index;
-            this.endIndex = endIndex;
+        private int index;
+
+        RowBuilder(int row) {
+            this.row = row;
+            this.index = row * columnCount;
+            this.endIndex = index + columnCount;
         }
 
         /**
@@ -210,6 +220,21 @@
             data[index++] = columnValue;
             return this;
         }
+
+        /**
+         * Offer value for possible inclusion if this cursor defines the given
+         * column. Columns not defined by the cursor are silently ignored.
+         *
+         * @return this builder to support chaining
+         */
+        public RowBuilder offer(String columnName, Object value) {
+            for (int i = 0; i < columnNames.length; i++) {
+                if (columnName.equals(columnNames[i])) {
+                    data[(row * columnCount) + i] = value;
+                }
+            }
+            return this;
+        }
     }
 
     // AbstractCursor implementation.
diff --git a/core/java/android/provider/DocumentsContract.java b/core/java/android/provider/DocumentsContract.java
index e1810ca..91d349a 100644
--- a/core/java/android/provider/DocumentsContract.java
+++ b/core/java/android/provider/DocumentsContract.java
@@ -36,6 +36,7 @@
 
 import libcore.io.IoUtils;
 
+import java.io.FileDescriptor;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
@@ -461,16 +462,27 @@
         final Bundle opts = new Bundle();
         opts.putParcelable(EXTRA_THUMBNAIL_SIZE, size);
 
-        InputStream is = null;
+        AssetFileDescriptor afd = null;
         try {
-            is = new AssetFileDescriptor.AutoCloseInputStream(
-                    resolver.openTypedAssetFileDescriptor(documentUri, "image/*", opts));
-            return BitmapFactory.decodeStream(is);
+            afd = resolver.openTypedAssetFileDescriptor(documentUri, "image/*", opts);
+
+            final FileDescriptor fd = afd.getFileDescriptor();
+            final BitmapFactory.Options bitmapOpts = new BitmapFactory.Options();
+
+            bitmapOpts.inJustDecodeBounds = true;
+            BitmapFactory.decodeFileDescriptor(fd, null, bitmapOpts);
+
+            final int widthSample = bitmapOpts.outWidth / size.x;
+            final int heightSample = bitmapOpts.outHeight / size.y;
+
+            bitmapOpts.inJustDecodeBounds = false;
+            bitmapOpts.inSampleSize = Math.min(widthSample, heightSample);
+            return BitmapFactory.decodeFileDescriptor(fd, null, bitmapOpts);
         } catch (IOException e) {
             Log.w(TAG, "Failed to load thumbnail for " + documentUri + ": " + e);
             return null;
         } finally {
-            IoUtils.closeQuietly(is);
+            IoUtils.closeQuietly(afd);
         }
     }
 
diff --git a/core/java/android/provider/MediaStore.java b/core/java/android/provider/MediaStore.java
index cb6300f..ad6839b 100644
--- a/core/java/android/provider/MediaStore.java
+++ b/core/java/android/provider/MediaStore.java
@@ -19,8 +19,8 @@
 import android.annotation.SdkConstant;
 import android.annotation.SdkConstant.SdkConstantType;
 import android.content.ContentResolver;
-import android.content.ContentValues;
 import android.content.ContentUris;
+import android.content.ContentValues;
 import android.content.Context;
 import android.database.Cursor;
 import android.database.DatabaseUtils;
@@ -532,7 +532,8 @@
         private static final Object sThumbBufLock = new Object();
         private static byte[] sThumbBuf;
 
-        private static Bitmap getMiniThumbFromFile(Cursor c, Uri baseUri, ContentResolver cr, BitmapFactory.Options options) {
+        private static Bitmap getMiniThumbFromFile(
+                Cursor c, Uri baseUri, ContentResolver cr, BitmapFactory.Options options) {
             Bitmap bitmap = null;
             Uri thumbUri = null;
             try {
@@ -577,6 +578,7 @@
                 if (c != null) c.close();
             }
         }
+
         /**
          * This method ensure thumbnails associated with origId are generated and decode the byte
          * stream from database (MICRO_KIND) or file (MINI_KIND).
diff --git a/core/tests/coretests/src/android/database/MatrixCursorTest.java b/core/tests/coretests/src/android/database/MatrixCursorTest.java
index cdab638..fc48c17 100644
--- a/core/tests/coretests/src/android/database/MatrixCursorTest.java
+++ b/core/tests/coretests/src/android/database/MatrixCursorTest.java
@@ -128,6 +128,56 @@
         } catch (IllegalArgumentException e) { /* expected */ }
     }
 
+    public void testRowBuilderOffer() {
+        MatrixCursor cursor = newMatrixCursor();
+
+        cursor.newRow()
+                .offer("float", 4.2f)
+                .offer("string", "foobar")
+                .offer("blob", new byte[] {(byte) 0xaa, (byte) 0x55})
+                .offer("lolwat", "kittens");
+
+        cursor.newRow();
+
+        cursor.newRow()
+                .offer("string", "zero")
+                .offer("string", "one")
+                .offer("string", "two")
+                .offer("lolwat", "kittens");
+
+        assertTrue(cursor.moveToFirst());
+        assertEquals("foobar", cursor.getString(0));
+        assertEquals(null, cursor.getString(1));
+        assertEquals(0, cursor.getShort(1));
+        assertEquals(0, cursor.getInt(2));
+        assertEquals(0, cursor.getLong(3));
+        assertEquals(4.2f, cursor.getFloat(4));
+        assertEquals(0.0d, cursor.getDouble(5));
+        MoreAsserts.assertEquals(new byte[] {(byte) 0xaa, (byte) 0x55}, cursor.getBlob(6));
+
+        assertTrue(cursor.moveToNext());
+        assertEquals(null, cursor.getString(0));
+        assertEquals(0, cursor.getShort(1));
+        assertEquals(0, cursor.getInt(2));
+        assertEquals(0, cursor.getLong(3));
+        assertEquals(0.0f, cursor.getFloat(4));
+        assertEquals(0.0d, cursor.getDouble(5));
+        assertEquals(null, cursor.getBlob(6));
+
+        assertTrue(cursor.moveToNext());
+        assertEquals("two", cursor.getString(0));
+        assertEquals(0, cursor.getShort(1));
+        assertEquals(0, cursor.getInt(2));
+        assertEquals(0, cursor.getLong(3));
+        assertEquals(0.0f, cursor.getFloat(4));
+        assertEquals(0.0d, cursor.getDouble(5));
+        assertEquals(null, cursor.getBlob(6));
+
+        assertTrue(cursor.isLast());
+        assertFalse(cursor.moveToNext());
+        assertTrue(cursor.isAfterLast());
+    }
+
     static class NonIterableArrayList<T> extends ArrayList<T> {
 
         NonIterableArrayList() {}
diff --git a/packages/DocumentsUI/src/com/android/documentsui/DirectoryFragment.java b/packages/DocumentsUI/src/com/android/documentsui/DirectoryFragment.java
index ac5629e..fbdb3a7 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/DirectoryFragment.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/DirectoryFragment.java
@@ -16,17 +16,24 @@
 
 package com.android.documentsui;
 
+import static com.android.documentsui.DocumentsActivity.TAG;
+
 import android.app.Fragment;
 import android.app.FragmentManager;
 import android.app.FragmentTransaction;
 import android.app.LoaderManager.LoaderCallbacks;
 import android.content.Context;
 import android.content.Loader;
+import android.graphics.Bitmap;
+import android.graphics.Point;
 import android.net.Uri;
+import android.os.AsyncTask;
 import android.os.Bundle;
 import android.provider.DocumentsContract;
 import android.text.format.DateUtils;
 import android.text.format.Formatter;
+import android.text.format.Time;
+import android.util.Log;
 import android.util.SparseBooleanArray;
 import android.view.ActionMode;
 import android.view.LayoutInflater;
@@ -75,6 +82,8 @@
 
     private int mType = TYPE_NORMAL;
 
+    private Point mThumbSize;
+
     private DocumentsAdapter mAdapter;
     private LoaderCallbacks<List<Document>> mCallbacks;
 
@@ -217,7 +226,9 @@
             choiceMode = ListView.CHOICE_MODE_NONE;
         }
 
+        final int thumbSize;
         if (state.mode == DisplayState.MODE_GRID) {
+            thumbSize = getResources().getDimensionPixelSize(R.dimen.grid_width);
             mListView.setAdapter(null);
             mListView.setChoiceMode(ListView.CHOICE_MODE_NONE);
             mGridView.setAdapter(mAdapter);
@@ -226,6 +237,7 @@
             mGridView.setChoiceMode(choiceMode);
             mCurrentView = mGridView;
         } else if (state.mode == DisplayState.MODE_LIST) {
+            thumbSize = getResources().getDimensionPixelSize(android.R.dimen.app_icon_size);
             mGridView.setAdapter(null);
             mGridView.setChoiceMode(ListView.CHOICE_MODE_NONE);
             mListView.setAdapter(mAdapter);
@@ -234,6 +246,8 @@
         } else {
             throw new IllegalStateException();
         }
+
+        mThumbSize = new Point(thumbSize, thumbSize);
     }
 
     private OnItemClickListener mItemListener = new OnItemClickListener() {
@@ -349,9 +363,21 @@
             final TextView date = (TextView) convertView.findViewById(R.id.date);
             final TextView size = (TextView) convertView.findViewById(R.id.size);
 
+            final ThumbnailAsyncTask oldTask = (ThumbnailAsyncTask) icon.getTag();
+            if (oldTask != null) {
+                oldTask.cancel(false);
+            }
+
             if (doc.isThumbnailSupported()) {
-                // TODO: load thumbnails async
-                icon.setImageURI(doc.uri);
+                final Bitmap cachedResult = ThumbnailCache.get(context).get(doc.uri);
+                if (cachedResult != null) {
+                    icon.setImageBitmap(cachedResult);
+                } else {
+                    final ThumbnailAsyncTask task = new ThumbnailAsyncTask(icon, mThumbSize);
+                    icon.setImageBitmap(null);
+                    icon.setTag(task);
+                    task.execute(doc.uri);
+                }
             } else {
                 icon.setImageDrawable(RootsCache.resolveDocumentIcon(
                         context, doc.uri.getAuthority(), doc.mimeType));
@@ -380,10 +406,11 @@
                         (summary.getVisibility() == View.VISIBLE) ? View.VISIBLE : View.GONE);
             }
 
-            // TODO: omit year from format
-            date.setText(DateUtils.formatSameDayTime(
-                    doc.lastModified, System.currentTimeMillis(), DateFormat.SHORT,
-                    DateFormat.SHORT));
+            if (doc.lastModified == -1) {
+                date.setText(null);
+            } else {
+                date.setText(formatTime(context, doc.lastModified));
+            }
 
             if (state.showSize) {
                 size.setVisibility(View.VISIBLE);
@@ -414,4 +441,66 @@
             return getItem(position).uri.hashCode();
         }
     }
+
+    private static class ThumbnailAsyncTask extends AsyncTask<Uri, Void, Bitmap> {
+        private final ImageView mTarget;
+        private final Point mSize;
+
+        public ThumbnailAsyncTask(ImageView target, Point size) {
+            mTarget = target;
+            mSize = size;
+        }
+
+        @Override
+        protected void onPreExecute() {
+            mTarget.setTag(this);
+        }
+
+        @Override
+        protected Bitmap doInBackground(Uri... params) {
+            final Context context = mTarget.getContext();
+            final Uri uri = params[0];
+
+            Bitmap result = null;
+            try {
+                result = DocumentsContract.getThumbnail(
+                        context.getContentResolver(), uri, mSize);
+                if (result != null) {
+                    ThumbnailCache.get(context).put(uri, result);
+                }
+            } catch (Exception e) {
+                Log.w(TAG, "Failed to load thumbnail: " + e);
+            }
+            return result;
+        }
+
+        @Override
+        protected void onPostExecute(Bitmap result) {
+            if (mTarget.getTag() == this) {
+                mTarget.setImageBitmap(result);
+                mTarget.setTag(null);
+            }
+        }
+    }
+
+    private static String formatTime(Context context, long when) {
+        // TODO: DateUtils should make this easier
+        Time then = new Time();
+        then.set(when);
+        Time now = new Time();
+        now.setToNow();
+
+        int flags = DateUtils.FORMAT_NO_NOON | DateUtils.FORMAT_NO_MIDNIGHT
+                | DateUtils.FORMAT_ABBREV_ALL;
+
+        if (then.year != now.year) {
+            flags |= DateUtils.FORMAT_SHOW_YEAR | DateUtils.FORMAT_SHOW_DATE;
+        } else if (then.yearDay != now.yearDay) {
+            flags |= DateUtils.FORMAT_SHOW_DATE;
+        } else {
+            flags |= DateUtils.FORMAT_SHOW_TIME;
+        }
+
+        return DateUtils.formatDateTime(context, when, flags);
+    }
 }
diff --git a/packages/DocumentsUI/src/com/android/documentsui/ThumbnailCache.java b/packages/DocumentsUI/src/com/android/documentsui/ThumbnailCache.java
new file mode 100644
index 0000000..bc7abeb
--- /dev/null
+++ b/packages/DocumentsUI/src/com/android/documentsui/ThumbnailCache.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2013 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.documentsui;
+
+import android.app.ActivityManager;
+import android.content.Context;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.util.LruCache;
+
+public class ThumbnailCache extends LruCache<Uri, Bitmap> {
+    private static ThumbnailCache sCache;
+
+    public static ThumbnailCache get(Context context) {
+        if (sCache == null) {
+            final ActivityManager am = (ActivityManager) context.getSystemService(
+                    Context.ACTIVITY_SERVICE);
+            final int memoryClassBytes = am.getMemoryClass() * 1024 * 1024;
+            sCache = new ThumbnailCache(memoryClassBytes / 4);
+        }
+        return sCache;
+    }
+
+    public ThumbnailCache(int maxSizeBytes) {
+        super(maxSizeBytes);
+    }
+
+    @Override
+    protected int sizeOf(Uri key, Bitmap value) {
+        return value.getByteCount();
+    }
+}
diff --git a/packages/ExternalStorageProvider/AndroidManifest.xml b/packages/ExternalStorageProvider/AndroidManifest.xml
index afdb6bb..5272166 100644
--- a/packages/ExternalStorageProvider/AndroidManifest.xml
+++ b/packages/ExternalStorageProvider/AndroidManifest.xml
@@ -7,7 +7,7 @@
     <application android:label="@string/app_label">
         <provider
             android:name=".ExternalStorageProvider"
-            android:authorities="com.android.externalstorage"
+            android:authorities="com.android.externalstorage.documents"
             android:grantUriPermissions="true"
             android:exported="true"
             android:permission="android.permission.MANAGE_DOCUMENTS">
diff --git a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
index 659139d..b4bf563 100644
--- a/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
+++ b/packages/ExternalStorageProvider/src/com/android/externalstorage/ExternalStorageProvider.java
@@ -22,10 +22,10 @@
 import android.content.UriMatcher;
 import android.database.Cursor;
 import android.database.MatrixCursor;
+import android.database.MatrixCursor.RowBuilder;
 import android.net.Uri;
 import android.os.Environment;
 import android.os.ParcelFileDescriptor;
-import android.provider.BaseColumns;
 import android.provider.DocumentsContract;
 import android.provider.DocumentsContract.DocumentColumns;
 import android.provider.DocumentsContract.Documents;
@@ -45,7 +45,7 @@
 public class ExternalStorageProvider extends ContentProvider {
     private static final String TAG = "ExternalStorage";
 
-    private static final String AUTHORITY = "com.android.externalstorage";
+    private static final String AUTHORITY = "com.android.externalstorage.documents";
 
     // TODO: support multiple storage devices
 
@@ -57,6 +57,14 @@
     private static final int URI_DOCS_ID_CONTENTS = 4;
     private static final int URI_DOCS_ID_SEARCH = 5;
 
+    static {
+        sMatcher.addURI(AUTHORITY, "roots", URI_ROOTS);
+        sMatcher.addURI(AUTHORITY, "roots/*", URI_ROOTS_ID);
+        sMatcher.addURI(AUTHORITY, "roots/*/docs/*", URI_DOCS_ID);
+        sMatcher.addURI(AUTHORITY, "roots/*/docs/*/contents", URI_DOCS_ID_CONTENTS);
+        sMatcher.addURI(AUTHORITY, "roots/*/docs/*/search", URI_DOCS_ID_SEARCH);
+    }
+
     private HashMap<String, Root> mRoots = Maps.newHashMap();
 
     private static class Root {
@@ -68,13 +76,15 @@
         public File path;
     }
 
-    static {
-        sMatcher.addURI(AUTHORITY, "roots", URI_ROOTS);
-        sMatcher.addURI(AUTHORITY, "roots/*", URI_ROOTS_ID);
-        sMatcher.addURI(AUTHORITY, "roots/*/docs/*", URI_DOCS_ID);
-        sMatcher.addURI(AUTHORITY, "roots/*/docs/*/contents", URI_DOCS_ID_CONTENTS);
-        sMatcher.addURI(AUTHORITY, "roots/*/docs/*/search", URI_DOCS_ID_SEARCH);
-    }
+    private static final String[] ALL_ROOTS_COLUMNS = new String[] {
+            RootColumns.ROOT_ID, RootColumns.ROOT_TYPE, RootColumns.ICON, RootColumns.TITLE,
+            RootColumns.SUMMARY, RootColumns.AVAILABLE_BYTES
+    };
+
+    private static final String[] ALL_DOCUMENTS_COLUMNS = new String[] {
+            DocumentColumns.DOC_ID, DocumentColumns.DISPLAY_NAME, DocumentColumns.SIZE,
+            DocumentColumns.MIME_TYPE, DocumentColumns.LAST_MODIFIED, DocumentColumns.FLAGS
+    };
 
     @Override
     public boolean onCreate() {
@@ -93,64 +103,59 @@
     @Override
     public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
             String sortOrder) {
-
-        // TODO: support custom projections
-        final String[] rootsProjection = new String[] {
-                BaseColumns._ID, RootColumns.ROOT_ID, RootColumns.ROOT_TYPE, RootColumns.ICON,
-                RootColumns.TITLE, RootColumns.SUMMARY, RootColumns.AVAILABLE_BYTES };
-        final String[] docsProjection = new String[] {
-                BaseColumns._ID, DocumentColumns.DISPLAY_NAME, DocumentColumns.SIZE,
-                DocumentColumns.DOC_ID, DocumentColumns.MIME_TYPE, DocumentColumns.LAST_MODIFIED,
-                DocumentColumns.FLAGS };
-
         switch (sMatcher.match(uri)) {
             case URI_ROOTS: {
-                final MatrixCursor cursor = new MatrixCursor(rootsProjection);
+                final MatrixCursor result = new MatrixCursor(
+                        projection != null ? projection : ALL_ROOTS_COLUMNS);
                 for (Root root : mRoots.values()) {
-                    includeRoot(cursor, root);
+                    includeRoot(result, root);
                 }
-                return cursor;
+                return result;
             }
             case URI_ROOTS_ID: {
                 final Root root = mRoots.get(DocumentsContract.getRootId(uri));
 
-                final MatrixCursor cursor = new MatrixCursor(rootsProjection);
-                includeRoot(cursor, root);
-                return cursor;
+                final MatrixCursor result = new MatrixCursor(
+                        projection != null ? projection : ALL_ROOTS_COLUMNS);
+                includeRoot(result, root);
+                return result;
             }
             case URI_DOCS_ID: {
                 final Root root = mRoots.get(DocumentsContract.getRootId(uri));
                 final String docId = DocumentsContract.getDocId(uri);
 
-                final MatrixCursor cursor = new MatrixCursor(docsProjection);
+                final MatrixCursor result = new MatrixCursor(
+                        projection != null ? projection : ALL_DOCUMENTS_COLUMNS);
                 final File file = docIdToFile(root, docId);
-                includeFile(cursor, root, file);
-                return cursor;
+                includeFile(result, root, file);
+                return result;
             }
             case URI_DOCS_ID_CONTENTS: {
                 final Root root = mRoots.get(DocumentsContract.getRootId(uri));
                 final String docId = DocumentsContract.getDocId(uri);
 
-                final MatrixCursor cursor = new MatrixCursor(docsProjection);
+                final MatrixCursor result = new MatrixCursor(
+                        projection != null ? projection : ALL_DOCUMENTS_COLUMNS);
                 final File parent = docIdToFile(root, docId);
 
                 for (File file : parent.listFiles()) {
-                    includeFile(cursor, root, file);
+                    includeFile(result, root, file);
                 }
 
-                return cursor;
+                return result;
             }
             case URI_DOCS_ID_SEARCH: {
                 final Root root = mRoots.get(DocumentsContract.getRootId(uri));
                 final String docId = DocumentsContract.getDocId(uri);
                 final String query = DocumentsContract.getSearchQuery(uri).toLowerCase();
 
-                final MatrixCursor cursor = new MatrixCursor(docsProjection);
+                final MatrixCursor result = new MatrixCursor(
+                        projection != null ? projection : ALL_DOCUMENTS_COLUMNS);
                 final File parent = docIdToFile(root, docId);
 
                 final LinkedList<File> pending = new LinkedList<File>();
                 pending.add(parent);
-                while (!pending.isEmpty() && cursor.getCount() < 20) {
+                while (!pending.isEmpty() && result.getCount() < 20) {
                     final File file = pending.removeFirst();
                     if (file.isDirectory()) {
                         for (File child : file.listFiles()) {
@@ -158,12 +163,12 @@
                         }
                     } else {
                         if (file.getName().toLowerCase().contains(query)) {
-                            includeFile(cursor, root, file);
+                            includeFile(result, root, file);
                         }
                     }
                 }
 
-                return cursor;
+                return result;
             }
             default: {
                 throw new UnsupportedOperationException("Unsupported Uri " + uri);
@@ -196,13 +201,17 @@
         }
     }
 
-    private void includeRoot(MatrixCursor cursor, Root root) {
-        cursor.addRow(new Object[] {
-                root.name.hashCode(), root.name, root.rootType, root.icon, root.title, root.summary,
-                root.path.getFreeSpace() });
+    private void includeRoot(MatrixCursor result, Root root) {
+        final RowBuilder row = result.newRow();
+        row.offer(RootColumns.ROOT_ID, root.name);
+        row.offer(RootColumns.ROOT_TYPE, root.rootType);
+        row.offer(RootColumns.ICON, root.icon);
+        row.offer(RootColumns.TITLE, root.title);
+        row.offer(RootColumns.SUMMARY, root.summary);
+        row.offer(RootColumns.AVAILABLE_BYTES, root.path.getFreeSpace());
     }
 
-    private void includeFile(MatrixCursor cursor, Root root, File file) {
+    private void includeFile(MatrixCursor result, Root root, File file) {
         int flags = 0;
 
         if (file.isDirectory()) {
@@ -223,8 +232,6 @@
         }
 
         final String docId = fileToDocId(root, file);
-        final long id = docId.hashCode();
-
         final String displayName;
         if (Documents.DOC_ID_ROOT.equals(docId)) {
             displayName = root.title;
@@ -232,8 +239,13 @@
             displayName = file.getName();
         }
 
-        cursor.addRow(new Object[] {
-                id, displayName, file.length(), docId, mimeType, file.lastModified(), flags });
+        final RowBuilder row = result.newRow();
+        row.offer(DocumentColumns.DOC_ID, docId);
+        row.offer(DocumentColumns.DISPLAY_NAME, displayName);
+        row.offer(DocumentColumns.SIZE, file.length());
+        row.offer(DocumentColumns.MIME_TYPE, mimeType);
+        row.offer(DocumentColumns.LAST_MODIFIED, file.lastModified());
+        row.offer(DocumentColumns.FLAGS, flags);
     }
 
     @Override