android-spinner

package zhang.spinner;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.widget.AdapterView;import android.widget.ArrayAdapter;import android.widget.Spinner;import android.widget.AdapterView.OnItemSelectedListener;public class Spinner_01 extends Activity {private Spinner spinner=null;    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        spinner=(Spinner)findViewById(R.id.spinner);                ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(        this,//上下文的引用        R.array.planets_array, //参数引用了string。xml文档中的String数组        android.R.layout.simple_spinner_item);//指定Spinner的样式，是一个布局id.由android系统据顶。也可以自己定义        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);                spinner.setAdapter(adapter);        spinner.setPrompt("test");        spinner.setOnItemSelectedListener(new onItemClick());            }    class onItemClick implements OnItemSelectedListener{public void onNothingSelected(AdapterView<?> adapterView){System.out.println("nothing selected");}public void onItemSelected(AdapterView<?>  adapterView, View view, int position,long id) {// TODO Auto-generated method stubString selected= adapterView.getItemAtPosition(position).toString();System.out.println(selected);} }                  }

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:orientation="vertical"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    ><Spinner    android:id="@+id/spinner"    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:prompt="@string/plant_prompt"    />    </LinearLayout>