Agfdhyk

I'm trying to implement a SearchView within a Toolbar for a ListFragment, but for some reason filtering is not working. The SearchView and keyboard appear as normal, but the ListView does not get filtered as I type something in.

fragment class

public class MyFragment extends ListFragment implements SearchView.OnQueryTextListener {



    public MyFragment() {}



    private ListView lv;

    private MyListAdapter mAdapter;



    public static MyFragment newInstance() {

        return new MyFragment();

    }



    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setHasOptionsMenu(true);

    }



    @Nullable

    @Override

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.fragment_list, container, false);

        initialize();

        return view;

    }



    List<Product> myList = new ArrayList<>();

    private void initialize() {

        String items = getActivity().getResources().getStringArray(R.array.product_names);

        String itemDescriptions = getActivity().getResources().getStringArray(R.array.product_descriptions);

        for (int n = 0; n < items.length; n++){

            Product product = new Product();

            product.setProductName(items[n]);

            product.setProductDescription(itemDescriptions[n]);

            myList.add(product);

        }



        mAdapter = new MyListAdapter(myList, getActivity());

        setListAdapter(mAdapter);

    }



    @Override

    public void onActivityCreated(Bundle savedInstanceState) {

        View v = getView();



        mTwoPane = getActivity().findViewById(R.id.detail_container) != null;



        assert v != null;

        lv = v.findViewById(android.R.id.list);

        lv.setTextFilterEnabled(true);

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override

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

                MyListAdapter adapter = (MyListAdapter) parent.getAdapter();

            }

        });



        super.onActivityCreated(savedInstanceState);

    }



    @Override

    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {

        MenuInflater mInflater = Objects.requireNonNull(getActivity()).getMenuInflater();

        mInflater.inflate(R.menu.menu_search, menu);



        MenuItem searchitem = menu.findItem(R.id.action_search);

        SearchView searchView = (SearchView) searchitem.getActionView();

        searchView.setQueryHint(Objects.requireNonNull(getContext()).getText(R.string.searchhint_productname));



        super.onCreateOptionsMenu(menu, inflater);

    }

}

adapter class

public class MyListAdapter extends BaseAdapter implements Filterable {



    private List<Product> myList;

    private List<Product> myListFull;

    private LayoutInflater mInflater;



    public MyListAdapter(List<Product> data, Context context) {

        myList = data;

        myList = new ArrayList(myList);

        myListFull = new ArrayList(myList);

        mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    }



    @Override

    public int getCount() {

        return myList.size();

    }



    @Override

    public Object getItem(int position) {

        return myList.get(position);

    }



    @Override

    public long getItemId(int position) {

        return position;

    }



    @Override

    public View getView(int position, View convertView, ViewGroup parent) {



        MyListAdapter.ViewHolder holder;



        if (convertView == null) {

            convertView = mInflater.inflate(R.layout.listitem, parent, false);

            holder = new MyListAdapter.ViewHolder();



            holder.title = convertView.findViewById(R.id.listitem_title);

            holder.description = convertView.findViewById(R.id.listitem_subtitle);



            convertView.setTag(holder);

        } else {

            holder = (MyListAdapter.ViewHolder) convertView.getTag();

        }





        Product mProduct = (Product)getItem(position);

        holder.title.setText(mProduct.getProductName());

        holder.description.setText(mProduct.getProductDescription());



        return convertView;

    }





    /**

     * View holder

     */

    static class ViewHolder {

        private TextView title;

        private TextView description;

    }



    @Override

    public Filter getFilter() {

        return exampleFilter;

    }



    private Filter exampleFilter = new Filter() {

        @Override

        protected FilterResults performFiltering(CharSequence constraint) {

            List<Product> filteredList = new ArrayList<>();



            if (constraint == null || constraint.length() == 0) {

                filteredList.addAll(myListFull);

            } else {

                String filterPattern = constraint.toString().toLowerCase().trim();



                for (Product item : myListFull) {

                    if (item.getProductName().toLowerCase().contains(filterPattern)) {

                        filteredList.add(item);

                    }

                }

            }



            FilterResults results = new FilterResults();

            results.values = filteredList;



            return results;

        }



        @Override

        protected void publishResults(CharSequence constraint, FilterResults results) {

            myList.clear();

            myList.addAll((List<Product>) results.values);

            notifyDataSetChanged();

        }

    };

}

You're missing OnQueryTextListener on your SearchView, simply attach one so that the adapter knows when to filter:

searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {

    @Override public boolean onQueryTextSubmit(String query) {

        return false;

    }



    @Override public boolean onQueryTextChange(String newText) {

        mAdapter.getFilter().filter(newText);

        return true;

    }

});