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POLoader not loading data when source data changes
 

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    <p>Android Documentation states that LOADERS - They monitor the source of their data and deliver new results when the content changes. I have changed CursorAdapter to work for a SQLite Database. </p> <pre><code>import android.content.ContentResolver; import android.content.Context; import android.database.ContentObserver; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.support.v4.content.AsyncTaskLoader; import android.support.v4.content.Loader.ForceLoadContentObserver; import android.util.Log; public class SimpleCursorLoader extends AsyncTaskLoader&lt;Cursor&gt; { final ForceLoadContentObserver mObserver; String mTable; String[] mColumns; String mSelection; String[] mSelectionArgs; String mGroupBy; String mHaving; String mOrderBy; String mLimit; Cursor mCursor; SQLiteDatabase mDb; /** * Creates an empty unspecified CursorLoader. You must follow this with * calls to {@link #setUri(Uri)}, {@link #setSelection(String)}, etc * to specify the query to perform. */ public SimpleCursorLoader(Context context) { super(context); mObserver = new ForceLoadContentObserver(); } /** * Creates a fully-specified SimpleCursorLoader. See * {@link ContentResolver#query(Uri, String[], String, String[], String) * ContentResolver.query()} for documentation on the meaning of the * parameters. These will be passed as-is to that call. */ public SimpleCursorLoader(Context context,String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy, String limit, SQLiteDatabase db) { super(context); mObserver = new ForceLoadContentObserver(); mTable = table; mColumns = columns; //copying array mSelection = selection; mSelectionArgs = selectionArgs; mGroupBy = groupBy; mHaving = having; mOrderBy = orderBy; mLimit = limit; mDb = db; } /* Runs on a worker thread */ @Override public Cursor loadInBackground() { Cursor cursor = mDb.query(mTable, mColumns, mSelection, mSelectionArgs, mGroupBy, mHaving, mOrderBy, mLimit); if (cursor != null) { // Ensure the cursor window is filled cursor.getCount(); Log.d("SimpleCursorLoader","Cursor.getCount()= " + String.valueOf(cursor.getCount())); registerContentObserver(cursor, mObserver); } return cursor; } /** * Registers an observer to get notifications from the content provider * when the cursor needs to be refreshed. */ void registerContentObserver(Cursor cursor, ContentObserver observer) { cursor.registerContentObserver(mObserver); } /* Runs on the UI thread */ @Override public void deliverResult(Cursor cursor) { Log.d("Gaurav","Inside SimpleCursorLoader - deliverResult"); if (isReset()) { // An async query came in while the loader is stopped if (cursor != null) { cursor.close(); } return; } Cursor oldCursor = mCursor; mCursor = cursor; if (isStarted()) { super.deliverResult(cursor); } if (oldCursor != null &amp;&amp; oldCursor != cursor &amp;&amp; !oldCursor.isClosed()) { oldCursor.close(); } } /** * Starts an asynchronous load of the contacts list data. When the result is ready the callbacks * will be called on the UI thread. If a previous load has been completed and is still valid * the result may be passed to the callbacks immediately. * * Must be called from the UI thread */ @Override protected void onStartLoading() { Log.d("Gaurav", "onStartLoading"); if (mCursor != null) { deliverResult(mCursor); } if (takeContentChanged() || mCursor == null) { forceLoad(); } } /** * Must be called from the UI thread */ @Override protected void onStopLoading() { // Attempt to cancel the current load task if possible. cancelLoad(); } @Override public void onCanceled(Cursor cursor) { if (cursor != null &amp;&amp; !cursor.isClosed()) { cursor.close(); } } @Override protected void onReset() { super.onReset(); // Ensure the loader is stopped onStopLoading(); if (mCursor != null &amp;&amp; !mCursor.isClosed()) { mCursor.close(); } mCursor = null; } } </code></pre> <p>The CursorLoader works in a ListFragment with a custom adapter which extends SimpleCursor Adapter and passes FLAG_REGISTER_CONTENT_OBSERVER in constructor but the cursor does changes when underlying data is changed by used response in the list.</p>
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    1. USGaurav Agarwal
    1. USGaurav Agarwal
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      1. VTUpMod
    2. VO
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      1. USmirel.cocosila
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    3. VO
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    1. COYou question is not exactly clear to me. Are you saying that your ListFragment does not refresh when the underlying data is changed?
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      1. UScodinguser
    2. CO@codinguser It is a old question, but that is what I meant.
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      1. USGaurav Agarwal
    3. CO@codingcrow did you happen to solve this problem?
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      1. USAds
 

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