Question

I’ve my main custom listactivity class that have a instance object of my custom extended class from ArrayAdapter. My Textwatcher is picking up character and searching fine over the adapter but when I press “Backspace” or “DEL” button to remove my character, my listview gets empty instead of showing all the records..

This is my activity.

adapter = new ProjectArrayAdapter(this, titles, statuses, ids, starteds);

                eTprojectsearch = (EditText) findViewById(R.id.txtprojectsearch);
                eTprojectsearch.addTextChangedListener(Listener__SearchProject);

                eTprojectsearch.setOnEditorActionListener(new OnEditorActionListener() {

                    @Override
                    public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
                        if(actionId == KeyEvent.KEYCODE_DEL) {
                            if(eTprojectsearch.getText().toString().trim().equals("")) {
                                setListAdapter(adapter);
                            }
                        }
                        return false;
                    }
                });              
                setListAdapter(adapter);

My function of Listener__SearchProject is..

private TextWatcher Listener__SearchProject = new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

            adapter.getFilter().filter(s);
            adapter.notifyDataSetChanged();
            //notifyAll();

            /*
             * if(s.length() == -1) {
                setListAdapter(adapter);
            } else {
                adapter.getFilter().filter(s,new Filter.FilterListener() {

                    public void onFilterComplete(int count) {
                        Log.i("ADAPTER:COMPLETE COUNT",String.valueOf(count));
                        adapter.setNotifyOnChange(true);
                    }
                });
            }
             */
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {
            // TODO Auto-generated method stub

        }

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

And here is my Adapter complete class with my Viewholder and etc.

public class ProjectArrayAdapter extends ArrayAdapter<String> implements Filterable {

    private final Activity context;
    private final List<String> titles;
    private final List<String> statuses;
    private final List<String> ids;
    private final List<String> starteds;
    ProjectFilter filter;
    public final Object mLock = new Object();

    ArrayList<String> items;
    ArrayList<String> filteredItems;

    static class PViewHolder {
        public TextView title;
        public TextView status;
        public TextView id;
        public TextView started;
    }

    public ProjectArrayAdapter(Activity context, List<String> titles,List<String> statuses,List<String> ids,List<String> starteds) {
        super(context, R.layout.projectlist, titles);
        this.context    = context;
        this.titles     = titles;
        this.statuses   = statuses;
        this.ids        = ids;
        this.starteds   = starteds;
        this.items = (ArrayList<String>)titles;
        this.filteredItems = this.items;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View rowView = convertView;
        if (rowView == null) {
            LayoutInflater inflater = context.getLayoutInflater();
            rowView = inflater.inflate(R.layout.projectlist, null);
            PViewHolder viewHolder = new PViewHolder();
            viewHolder.title        = (TextView) rowView.findViewById(R.id.projecttitle);
            viewHolder.status       = (TextView) rowView.findViewById(R.id.projectstatus);
            viewHolder.id           = (TextView) rowView.findViewById(R.id.projectid); 
            viewHolder.started      = (TextView) rowView.findViewById(R.id.projectstarted);
            rowView.setTag(viewHolder);
        }

        PViewHolder holder = (PViewHolder) rowView.getTag();
        String title        = titles.get(position);
        String status       = statuses.get(position);
        String id           = ids.get(position);
        String started      = starteds.get(position);
        holder.title.setText((title.length() > 17 ? title.substring(0, 17)+"..." : title));
        holder.status.setText(status);
        holder.id.setText(id);
        holder.started.setText(started);
        return rowView;

    }

    public Filter getFilter() {
        if (filter == null){
            filter = new ProjectFilter();
        }
        return filter;
    }

    private class ProjectFilter extends Filter {         

        @SuppressWarnings({ "rawtypes", "unchecked" })
        @Override
        protected FilterResults performFiltering(CharSequence prefix) {            
            FilterResults results = new FilterResults();

            if (prefix == null || prefix.length() == 0) {
                synchronized (mLock) {
                    results.values = items;
                    results.count = items.size();
                }
            } else {
                synchronized(mLock) {
                    String prefixString = prefix.toString().toLowerCase();
                    final ArrayList filteredItems = new ArrayList();
                    final ArrayList localItems = new ArrayList();
                    localItems.addAll(items);
                    final int count = localItems.size();
                    for (int i = 0; i < count; i++) {
                        final String cString = String.valueOf(localItems.get(i));
                        if (cString.contains(prefixString.toLowerCase())) {
                            filteredItems.add(cString);
                        }                        
                    }

                    results.values = filteredItems;
                    results.count = filteredItems.size();
                }//end synchronized
            }

            return results;
        }

        protected void publishResults(CharSequence prefix, FilterResults results) {
            synchronized(mLock) {
                @SuppressWarnings("unchecked")
                final ArrayList<String> localItems = (ArrayList<String>) results.values;
                notifyDataSetChanged();
                clear();
                for (Iterator<String> iterator = localItems.iterator(); iterator
                        .hasNext();) {
                    String gi = (String) iterator.next();
                    add(gi);
                }
            }//end synchronized
        }
    }
}

Please point me out where I’m mistaken..

Answer 1

ArrayList<String> items and ArrayList<String> filteredItems in ProjectArrayAdapter and List<T> mObjects; in ArrayAdapter refer to the same ArrayList instance. (Call clear() method of ArrayAdapter, then check items.size() it must be zero.)

1. Remove this line adapter.notifyDataSetChanged(); from onTextChanged

2. Replace this.items = (ArrayList<String>)titles; (in constructor) with this.items = new ArrayList<String>(titles);

3. publishResults() method should look like…

       synchronized(mLock) {
           final ArrayList<String> localItems = (ArrayList<String>) results.values;
           clear();
           for (String gi : localItems) {
               add(gi);
           }
           notifyDataSetChanged();
       }
   

Are you sure you need ArrayList<String> filteredItems; in ProjectArrayAdapter? Remove it unless it is necessary.