如何从ListFragment显示/隐藏Activity视图

Question

I have the classic ListActivity - ListFragment design with the ListFragment fetching data via a cursor Loader.

There are 2 possible outcomes in the basic arrangement -

the cursor is either empty or has data.

With data the list_row.xml is populated with items from the database.

If empty, I get a blank screen with no information for the user.

I have setup a TextView <i>"No records found message"</i> that can be be made Visible or Invisible from the ListFragment. The problem is:

1. ListFragment cannot access Views on the ListActivity.
2. How do I call the following ListActivity method from the ListFragment?

public void updateView(boolean data) {

        if (data) {         
             noRecordsFound.setVisibility(View.GONE);       
        } else {            
             noRecordsFound.setVisibility(View.VISIBLE);
        }
    }

I have tried to access from the onLoadFinished of the ListFragment , but this is not accessble. Any help?

Answer 1

Thanks to MH for the alternative approach, but I have bumped onto an answer to my own question. While I think MH's answer is the most suitable for my case, I include a solution to what I originally wanted to do just in case someone needs to use it for things other than listviews.

Well, I included the if (cursor.getCount() < 1) block inside the onLoadFinished() of the Cursor Loader, kike so:

@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {

    if (cursor.getCount() < 1) {

        TextView noNotes    = (TextView) getActivity().findViewById(R.id.noNotes);
        noNotes.setVisibility(View.GONE);
    }
    adapter.swapCursor(cursor);
}

Answer 2

As per earlier comment:

I don't really understand your first issue, since the view should be part of your fragment's layout, not the activity's, right?

With respect to toggling the 'empty' message: why don't you simply use the built-in functionality of setEmptyView(...) of ListView or setEmptyText(...) of ListFragment (also available in the support libary)? The first allows you to display a more complex view hierarchy for the empty message, in case you need to