Spinner simpleAdapte适配器 下拉列表

public class MainActivity extends AppCompatActivity {
    private TextView text;
    private Spinner spinner;

    private SimpleAdapter adapter;
    private List<Map<String,Object>> data;

    private String[] place = {"北京","上海","深圳","佛山"};

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

        //注册控件
        text = (TextView)findViewById(R.id.txt);
        spinner=(Spinner)findViewById(R.id.spinner);

        //数据源
        data = new ArrayList<Map<String,Object>>();
        getdata();

        //适配器
        adapter = new SimpleAdapter(this,data,R.layout.item,new String[]{"pic","txt"},new int[]{R.id.picture,R.id.name});
        adapter.setDropDownViewResource(R.layout.item);

        spinner.setAdapter(adapter);
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                text.setText("您选择的是：" + adapter.getItem(position));
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                text.setText("None");
            }
        });
    }
    private void getdata() {
        for(int i= 0; i < place.length; i++){
            Map<String,Object> map = new HashMap<String, Object>();
            map.put("pic",R.drawable.address_book);
            map.put("txt",place[i]);
            data.add(map);
        }
    }