android studio spinner控件

array.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources>
<array name="cars">
<item>宝马</item>
<item>大众</item>
<item>奔驰</item>
</array>
</resources>

第一种方法，使用adapter，感觉这个应该是淘汰的方法：

public class MainActivity extends AppCompatActivity {
Spinner spinner;
TextView textView;
ArrayAdapter<CharSequence> arrayAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
spinner=(Spinner)findViewById(R.id.spinner);
textView=(TextView)findViewById(R.id.textView);
arrayAdapter=ArrayAdapter.createFromResource(this,R.array.countries,android.R.layout.simple_spinner_item);
arrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(arrayAdapter);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
textView.setText("select "+adapterView.getItemAtPosition(i));
}

@Override
public void onNothingSelected(AdapterView<?> adapterView) {

}
});

}
}

第二种，在layout中spinner组件：

<Spinner
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/spinnercar"
android:entries="@array/cars"/>