AutoCompleteTextView Text Filtering

Question

I am trying to use AutoCompleteTextView for filtering and I'm having a problem with the filter. It returns all the Items in the ArrayList instead of the filtered ones. Below is my code:

 Filter nameFilter = new Filter() {
    @Override
    public String convertResultToString(Object resultValue) {
        String str = ((State)(resultValue)).getName();
        Log.e("Conv"+TAG, str);
        return str;
    }
    @Override
    protected FilterResults performFiltering(CharSequence constraint) {
        if(constraint != null) {
            suggestions.clear();
            for (State customer : itemsAll) {
                Log.e("Ite "+TAG, "" + itemsAll.size());
                Log.e("Cons " + TAG, constraint.toString());
                Log.e("Sta" + TAG, customer.getName()); //This is always null
                if(customer.getName().toLowerCase().contains(constraint.toString().toLowerCase())) {
                    suggestions.add(customer);
                }
            }
            FilterResults filterResults = new FilterResults();
            filterResults.values = suggestions;
            filterResults.count = suggestions.size();
            return filterResults;
        } else {
            return new FilterResults();
        }
    }
    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {
        List<State> filteredList = (ArrayList<State>) results.values;
        if(results != null && results.count > 0) {
            clear();
            Log.e("D "+TAG, ""+results.count);
            for (State c : filteredList) {
                Log.e("The "+TAG, c.getName() + " " + c.getId());
                add(c);
                notifyDataSetChanged();
            }
        } else {
            Log.e(TAG, "Empty Filter");
            notifyDataSetChanged();
        }
    }
};

And then I started logging around and I noticed this line is always null Log.e("Sta" + TAG, customer.getName()); //This is always null while this line Log.e("Cons " + TAG, constraint.toString()); and this line Log.e("Ite "+TAG, "" + itemsAll.size()); is never null. Constraint can't be null for sure unless no text was passed. But, for first object to be null when itemsAll.size() is not null or empty. I am confused. And below, is my List initialization

private static final String TAG = "StateAdapter";
private ArrayList<State> items;
private ArrayList<State> itemsAll;
private ArrayList<State> suggestions;
private Context context;
private int viewResourceId;

public StateAutoCompleteAdapter(Context context, int resource, int textViewResourceId, ArrayList<State> objects) {
    super(context, resource, textViewResourceId, objects);
    this.context = context;
    this.items = objects;
    this.itemsAll = new ArrayList<State>(items);
    this.suggestions = new ArrayList<State>();
    this.viewResourceId = resource;
}

And for the getView function

public View getView(int position, View convertView, ViewGroup parent) {
    View v = convertView;
    if (v == null) {
        LayoutInflater vi = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        v = vi.inflate(viewResourceId, null);
    }
    State customer = items.get(position);
    if (customer != null) {
        TextView customerNameLabel = (TextView) v.findViewById(R.id.bakerName);
        TextView bakerAddress = (TextView) v.findViewById(R.id.bakerAddress);
        if (customerNameLabel != null) {
//              Log.i(MY_DEBUG_TAG, "getView Customer Name:"+customer.getName());
            customerNameLabel.setText(customer.getName());
            bakerAddress.setVisibility(View.GONE);
        }
    }
    return v;
}

Answer 1

So, I fixed the problem myself doing this. So, I use a normal BaseAdapter and extend Filterable So, for those that may need how to use RealmDB with AutoCompleteTextView there you go

 public class LgasAutoCompleteAdapter extends BaseAdapter implements Filterable {

private static final String TAG = "LgasAutoComp";
private Context mContext;
private List<Lga> mResult = new ArrayList<>();
private LayoutInflater inflater;

public LgasAutoCompleteAdapter(Context mContext) {
    this.mContext = mContext;
}

@Override
public int getCount() {
    return mResult.size();
}

@Override
public Object getItem(int position) {
    return mResult.get(position);
}

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

@Override
public View getView(int position, View view, ViewGroup parent) {
    if (inflater == null)
        inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    if (view == null)
        view = inflater.inflate(R.layout.item_baker_autocomplete, parent, false);

    Lga lga = mResult.get(position);

    TextView customerNameLabel = (TextView) view.findViewById(R.id.bakerName);
    TextView bakerAddress = (TextView) view.findViewById(R.id.bakerAddress);

    if (lga != null) {
        if (customerNameLabel != null) {
//              Log.i(MY_DEBUG_TAG, "getView Customer Name:"+customer.getName());
            customerNameLabel.setText(lga.getName());
            bakerAddress.setVisibility(View.GONE);
        }
    }

    return view;
}

@Override
public Filter getFilter() {
    return new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence charSequence) {
            return null;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults filterResults) {
            if (constraint != null) {
                //String query = constraint.toString().toLowerCase();
                mResult = filterStates(constraint.toString());
                Log.e(TAG, ""+mResult.size());
                notifyDataSetChanged();
            } else {
                notifyDataSetInvalidated();
            }
        }
    };
}

@NonNull
private List<Lga> filterStates(String query) {
    Realm mRealm = RealmUtils.getRealmInstance(mContext);
    return mRealm.where(Lga.class)
            .contains("name", query)
            .or()
            .beginsWith("name", query)
            .findAll();
}
}

Answer 2

clear() method might be causing problem. So please check its code for which array list you are cleaning.

Another problem is because you are using State customer = items.get(position); in getView() and using suggestions.add(customer); in performFiltering(CharSequence constraint)

Hope this helps.