Question

I follow example from here using section listview
http://lalit3686.blogspot.com/2012/05/sectionadapter.html

But how can I implement adapter.notifyDataSetChanged()?

Adding listener to update the listview data:

mListView.setOnItemClickListener(new OnItemClickListener() {

        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

            Toast.makeText(SectionAdapterActivity.this, ""+position+"", Toast.LENGTH_SHORT).show();
            test();

        }
    });

I’m adding new function only for change/update value (testing only):

public void test()
{
    hashMap.clear();

    for (int i = 0; i < 3; i++) {
        hashMap.put("Mail", String.valueOf(1100 + i), 1);
    }

    for (int j = 0; j < 4; j++) {
        hashMap.put("Case", String.valueOf(2100 + j), 15);
    }
    for (int j = 0; j < 5; j++) {
        hashMap.put("File", String.valueOf(10000 + j), 20);
    }

    mListView.invalidate();
    mListView.invalidateViews();
    adapter.notifyDataSetChanged(); 

    Log.e("dada", hashMap.toString());
}}

Seems like does not work, can anyone help?

Answer 1

I don’t understand exactly what you are trying to achieve with calling notifyDataSetChange().

this method is taking affect only when you change the logic data collection / database which been used by the adapter, after it has created already. in this situation – it would cause to update of the list with the new data

if that’s what you want to do, then to use it – what you need to do is simple: just call:

adapter.notifyDataSetChanged();

and that’s it :). nothing else.