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    <p>I was facing the same problem. In fact, I think a lot of people are. The whole mechanism of URI - to Relational DB through contentprovider, and everything that was built around it (like the various change listeners, file and stream handling) - this is all very impressive and useful, but for very simple data models.</p> <p>Once your application needs a more elaborate data model, like - a hierarchy of tables, object relational semantics - this model breaks. I've found a bunch of ORM tools for Android, but they seem too 'bleeding edge' to me (plus, for the life of me, I couldn't figure out if they have data change notification support).</p> <p>ORM is very common today, I really hope the Android folks agree and add ORM capabilities to the platform.</p> <p>This is what I ended up doing: A cursor of cursors, with a a leading index cursor that helps choose the correct internal curosr. It's kind of a temp solution, I just needed to move on with my code and get back to this later. Hope this helps. Of course if you use a listview, you probably need to also create a custom adapter to inflate the correct views, and do the binding.</p> <pre><code>public class MultiCursor implements Cursor { private final String TAG = this.getClass().getSimpleName(); ArrayList&lt;Cursor&gt; m_cursors = new ArrayList&lt;Cursor&gt;(); Map&lt;Long, CursorRowPair&gt; m_idToCursorRow = Collections.synchronizedMap(new HashMap&lt;Long, CursorRowPair&gt;()); Set&lt;Long&gt; m_idSet = new HashSet&lt;Long&gt;(); Cursor m_idCursor; /** * @precondition: _id column must exist on every type of cursor, and has to have index of 0 (be the first) * @param idCursor */ public MultiCursor(Cursor idCursor) { m_idCursor = idCursor;// this cursor binds the order (1,2,3) to ids // go over all the ids in id cursor and add to m_idSet initIdSet(); // m_cursors.add(idCursor); // m_position = -1; } private void initIdSet() { m_idSet.clear(); long id; m_idCursor.moveToPosition(-1); while (m_idCursor.moveToNext()) { id = m_idCursor.getLong(m_idCursor.getColumnIndex(ContentDescriptor.ShowViewItem.Cols.ID)); m_idSet.add(id); } m_idCursor.moveToFirst(); } public void addCursor(Cursor cursor) { // when something changes in the child cursor, notify parent on change, to notify subscribers // cursor.registerContentObserver(new SelfContentObserver(this)); // calls my onchange, which calls the ui m_cursors.add(cursor); updateIdToCursorMap(cursor); } private class CursorRowPair { public final Cursor cursor; public final int row; public CursorRowPair(Cursor cursor, int row) { this.cursor = cursor; this.row = row; } } private void updateIdToCursorMap(Cursor cursor) { // get object_type // for each row in cursor, take id, row number // add id, &lt;cursor,rowNum&gt; to map long id; int row = 0; cursor.moveToPosition(-1); while (cursor.moveToNext()) { id = cursor.getLong(cursor.getColumnIndex(ContentDescriptor.ShowViewItem.Cols.ID)); if (m_idSet.contains(id)) m_idToCursorRow.put(id, new CursorRowPair(cursor, row)); row++; } cursor.moveToFirst(); } private Cursor getInternalCursor() { if (getPosition() &lt; 0 || getCount()==0) return m_idCursor; // todo throw a proper exception // get the id of the current row long id = m_idCursor.getLong(m_idCursor.getColumnIndex(ContentDescriptor.BaseCols.ID)); CursorRowPair cursorRowPair = m_idToCursorRow.get(id); if (null == cursorRowPair) return null; Cursor cursor = cursorRowPair.cursor; int row = cursorRowPair.row; cursor.moveToPosition(row); return cursor; } // ////////////////////////////////////////////// @Override public void close() { Log.d(TAG, "close"); for (Cursor cursor : m_cursors) { cursor.close(); } m_idCursor.close(); } @Override public void copyStringToBuffer(int columnIndex, CharArrayBuffer buffer) { Log.d(TAG, "copyStringToBuffer"); getInternalCursor().copyStringToBuffer(columnIndex, buffer); } </code></pre> <p>etc etc etc.</p>
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    1. COYeah, there are lot of different Cursors (like MatrixCursor) but they didn't fit here. This solution looks nice, however a custom `AsyncTaskLoader` worked for me perfectly too.
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    2. CORecently refactored my code, pulled the code above out, and did a sort of small ORMapping implementation. Created my own loaders that return List<BaseObject>, and every element type extended BaseOject.
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