下拉列表Spinner 、自动补齐AutoCompleteTextView、

public class Main2Activity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);

Spinner spinner = (Spinner) findViewById(R.id.spinner);

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item);
adapter.add("JAVA");
adapter.add("c");

spinner.setAdapter(adapter);

}

public class Main2Activity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);

String[] names =new String[]{"人","中国","李丽","abc"};
AutoCompleteTextView textView = (AutoCompleteTextView) findViewById(R.id.auto);

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_dropdown_item_1line,names);

textView.setAdapter(adapter);

}