Filter ListView with arrayadapter

Question

I\'m trying to filter a listview with arrayadapter. The arraydapter parameter is a String[][]. The problem is that anything happens. I must override the Filter interface? In

Answer 1

Convert your String array to ArrayList and pass it to Adapter and use below code or change below code with your String[].

You need to implement Filterable to your Adapter class and Override getFilter()

Checkout this complete example for filtering custom Adapter.

public class ListFilterActivity extends ListActivity {

    private List list = new ArrayList();
    List mOriginalValues;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final MyAdapter adapter = new MyAdapter(this, getModel());
        setListAdapter(adapter);

        EditText filterEditText = (EditText) findViewById(R.id.filterText);

        // Add Text Change Listener to EditText
        filterEditText.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
                // Call back the Adapter with current character to Filter
                adapter.getFilter().filter(s.toString());
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,int after) {
            }

            @Override
            public void afterTextChanged(Editable s) {
            }
        });
    }

    private List getModel() {
        list.add("Linux");
        list.add("Windows7");
        list.add("Suse");
        list.add("Eclipse");
        list.add("Ubuntu");
        list.add("Solaris");
        list.add("Android");
        list.add("iPhone");
        list.add("Windows XP");
        return list;
    }
}

// Adapter Class
public class MyAdapter extends BaseAdapter implements Filterable {

    List arrayList;
    List mOriginalValues; // Original Values
    LayoutInflater inflater;

    public MyAdapter(Context context, List arrayList) {
        this.arrayList = arrayList;
        inflater = LayoutInflater.from(context);
    }

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

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

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

    private class ViewHolder {
        TextView textView;
    }

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

        ViewHolder holder = null;

        if (convertView == null) {

            holder = new ViewHolder();
            convertView = inflater.inflate(R.layout.row, null);
            holder.textView = (TextView) convertView
            .findViewById(R.id.textview);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        holder.textView.setText(arrayList.get(position));
        return convertView;
    }

    @Override
    public Filter getFilter() {
        Filter filter = new Filter() {

            @SuppressWarnings("unchecked")
            @Override
            protected void publishResults(CharSequence constraint,FilterResults results) {

                arrayList = (List) results.values; // has the filtered values
                notifyDataSetChanged();  // notifies the data with new filtered values
            }

            @Override
            protected FilterResults performFiltering(CharSequence constraint) {
                FilterResults results = new FilterResults();        // Holds the results of a filtering operation in values
                List FilteredArrList = new ArrayList();

                if (mOriginalValues == null) {
                    mOriginalValues = new ArrayList(arrayList); // saves the original data in mOriginalValues
                }

                /********
                *
                *  If constraint(CharSequence that is received) is null returns the mOriginalValues(Original) values
                *  else does the Filtering and returns FilteredArrList(Filtered)
                *
                ********/
                if (constraint == null || constraint.length() == 0) {

                    // set the Original result to return
                    results.count = mOriginalValues.size();
                    results.values = mOriginalValues;
                } else {
                    constraint = constraint.toString().toLowerCase();
                    for (int i = 0; i < mOriginalValues.size(); i++) {
                        String data = mOriginalValues.get(i);
                        if (data.toLowerCase().startsWith(constraint.toString())) {
                            FilteredArrList.add(data);
                        }
                    }
                    // set the Filtered result to return
                    results.count = FilteredArrList.size();
                    results.values = FilteredArrList;
                }
                return results;
            }
        };
        return filter;
    }
}