Loader can not be restarted after orientation changed

I'd like to use a demo to show this: ``` enter code here @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button button = (Button) findViewById(R.id.button1); button.setOnClickListener(buttonClickListener); } private OnClickListener buttonClickListener = new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub startMyLoader(); } }; private void startMyLoader() { getLoaderManager().destroyLoader(0); getLoaderManager().restartLoader(0, null, myLoaderListener); } /** * The listener for the group metadata loader. */ private final LoaderManager.LoaderCallbacks<Cursor> myLoaderListener = new LoaderCallbacks<Cursor>() { @Override public CursorLoader onCreateLoader(int id, Bundle args) { return new CursorLoader(LoaderDemoActivity.this, ContactsContract.Contacts.CONTENT_URI, null, null, null, null); } @Override public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) { cursor.moveToPosition(-1); if (cursor.moveToNext()) { Context context = getApplicationContext(); CharSequence text = "Load finished!"; int duration = Toast.LENGTH_SHORT; Toast toast = Toast.makeText(context, text, duration); toast.show(); } } @Override public void onLoaderReset(Loader<Cursor> loader) { } }; enter code here ``` After orientation changed, I clicked the button, the onCreateLoader can be called, but onLoadFinished will not be called. It seems strange. Thanks for help in advance.