AutoCompleteTextView自定義Filter

package com.example.autocompletetextviewtest;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AutoCompleteTextView;
import android.widget.BaseAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;

public class MainActivity extends Activity {
	private ArrayList<String> mCountries = new ArrayList<String>();
	private List<String> mFilterData;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		initData();
		setContentView(R.layout.activity_main);

		AutoCompleteTextView autoTxt = (AutoCompleteTextView) findViewById(R.id.auto_txt);
		autoTxt.setAdapter(new MyAdapter());
	}

	private void initData() {
		List<String> list = Arrays.asList(getResources().getStringArray(R.array.tag));
		mCountries.addAll(list);
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	public class MyAdapter extends BaseAdapter implements Filterable {

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

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

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

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			ViewHolder holder = null;
			if (convertView == null) {
				holder = new ViewHolder();
				LayoutInflater inflater = LayoutInflater.from(MainActivity.this);
				convertView = inflater.inflate(R.layout.simple_list_item_for_autocomplete, null);
				holder.tv = (TextView) convertView.findViewById(R.id.simple_item_0);
				convertView.setTag(holder);
			} else {
				holder = (ViewHolder) convertView.getTag();
			}
			
			holder.tv.setText(mFilterData.get(position));
			return convertView;
		}

		@Override
		public Filter getFilter() {
			return new Filter() {

				@Override
				protected FilterResults performFiltering(CharSequence constraint) {
					Log.d("AutoCompleteTest",
							String.format("prefix = %s", constraint));
					FilterResults result = new FilterResults();
					ArrayList<String> newData = new ArrayList<String>();
					int size = mCountries.size();
					for (int i = 0; i < size; i++) {
						String item = mCountries.get(i);
						if (item.contains(constraint)) {
							newData.add(item);
						}
					}
					result.values = newData;
					result.count = newData.size();
					return result;
				}

				@Override
				protected void publishResults(CharSequence constraint,
						FilterResults results) {
					mFilterData = (List<String>) results.values;
					if (results.count > 0) {
						notifyDataSetChanged();
					} else {
						notifyDataSetInvalidated();
					}
				}

			};
		}

		class ViewHolder {
			TextView tv;
		}

	}
}