Android编程之下拉菜单Spinner控件用法示例

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="vertical" >  <TextView    android:id="@+id/textView"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:textSize="25sp"    android:textColor="#ff0000"    />  <Spinner    android:id="@+id/spinner"    android:layout_width="match_parent"    android:layout_height="wrap_content" /></LinearLayout>

package com.example.hello;import java.util.ArrayList;import java.util.List;import android.support.v7.app.ActionBarActivity;import android.os.Bundle;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.widget.AdapterView;import android.widget.AdapterView.OnItemSelectedListener;import android.widget.ArrayAdapter;import android.widget.Spinner;import android.widget.TextView;public class MainActivity extends ActionBarActivity implements OnItemSelectedListener{  private TextView textView;  private Spinner spinner;  private List<String> list;  private ArrayAdapter<String> adapter;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    textView = (TextView) findViewById(R.id.textView);    textView.setText("您选择的城市是：");    spinner = (Spinner) findViewById(R.id.spinner);    list = new ArrayList<String>();    list.add("北京");    list.add("上海");    list.add("广州");    list.add("深圳");    adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,list);    adapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);    spinner.setAdapter(adapter);    spinner.setOnItemSelectedListener(this);  }  @Override  public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2,long arg3) {    String cityName = adapter.getItem(arg2);    //String city = list.get(arg2);    textView.setText("您选择的城市是："+cityName);  }  @Override  public void onNothingSelected(AdapterView<?> arg0) {    // TODO Auto-generated method stub  }}