The `onLoaderReset()` is only called when the user presses the back button and not when calling `restartLoader()`. A related issue is discussed here https://code.google.com/p/android/issues/detail?id=68896

MainActivity.java

public class MainActivity extends AppCompatActivity implements LoaderManager.LoaderCallbacks<Cursor> {

    public static final String LOG_TAG = MainActivity.class.getSimpleName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        Log.e(LOG_TAG, "<======================calling create=======================>");
        getSupportLoaderManager().initLoader(1, null, this);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Log.e(LOG_TAG, "<======================calling restart=======================>");
                getSupportLoaderManager().restartLoader(1, null, MainActivity.this);
            }
        });
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.e(LOG_TAG, "<======================calling destroy=======================>");
        getSupportLoaderManager().destroyLoader(1);
    }

    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        Log.e(LOG_TAG, "onCreateLoader()");
        return new CursorLoader(this, Uri.parse("content://www.test.com/a"),
                null, null, null, null);
    }

    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
        Log.e(LOG_TAG, "onLoadFinish()");
    }

    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        Log.e(LOG_TAG, "onLoaderReset()");
    }
}