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notifyDataSetChanged() doesn't work

i got this problem yesterday: Here I have a list returned by server, and there is a Hashmap list(List) and a Hashmap inside the list.And I got two situations, one is when the hashmap list is null, I add a new item into it,and then call notifyDataSetChanged() doesn't work, and the other situation is when i changed the value in hashmap, and notifyDataSetChanged(), it doesn't refresh either.And I'm sure the data has been changed successfully.

it shows in A activity and changed data in B activity.

A activity:

protected List<CommentEntity> mDataList;
protected ListView mListView;
protected BaseListAdapter mAdapter;

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    int position = data.getIntExtra("position", -1);
    if (position > -1) {
        CommentEntity entity = (CommentEntity) data.getSerializableExtra(AppVars.Keys.EXTRA_ENTITY);
        mDataList.set(position, entity); // I want this list update
        mAdapter.notifyDataSetChanged();
    } else {
        // error
    }
}
public class BaseListAdapter extends BaseAdapter {

    @Override
    public int getCount() {
        return mDataList == null ? 0 : mDataList.size();
    }

    @Override
    public Object getItem(int position) {
        return mDataList == null ? null : mDataList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // actually this adapter is written in MyBaseFragment, and the child
        // Fragment will override setupItemView() method.it's working fine
        return setupItemView(position, convertView, parent);
    }
}

B activity:

private CommentEntity mCommentEntity;
// the list below is inside CommentEntity, QuoteEntity is extends HashMap<>.
private List<QuoteEntity> mQuoteList;
private QuoteAdapter mAdapter;
public void update(QuoteEntity newQuote) {
    mQuoteList.add(newQuote);
    mCommentEntity.setReplyRows(mQuoteList);
    mAdapter.notifyDataSetChanged();// This adapter is just working fine.
    setResult(-1, getIntent().putExtra(AppVars.Keys.EXTRA_ENTITY, mCommentEntity));
}

Try resetting listview instead of using notifyDataSetChanged();

           ListView lv = (ListView)FindViewById(R.id.lv);
           BaseListAdapter aa = new BaseListAdapter(//constructor's parameters);
           lv.setAdapter(aa);

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