Android使用Spinner控件实现下拉列表的案例

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:paddingBottom="@dimen/activity_vertical_margin"  android:paddingLeft="@dimen/activity_horizontal_margin"  android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"  tools:context=".MainActivity" >  <TextView    android:id="@+id/textView1"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_alignParentLeft="true"    android:layout_alignParentTop="true"    android:layout_marginTop="46dp"    android:text="所属城市"    android:textSize="22sp" />  <Spinner    android:id="@+id/spinner1"    android:layout_width="200sp"    android:layout_height="wrap_content"    android:layout_alignParentTop="true"    android:layout_marginTop="44dp"    android:layout_toRightOf="@+id/textView1" />  <TextView    android:id="@+id/textView2"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_alignRight="@+id/textView1"    android:layout_centerVertical="true"    android:text="所属星球" />  <Spinner    android:id="@+id/spinner2"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_alignLeft="@+id/spinner1"    android:layout_alignTop="@+id/textView2"    android:layout_marginLeft="21dp" /></RelativeLayout>

package com.example.spinners;import java.util.ArrayList;import java.util.List;import android.app.Activity;import android.os.Bundle;import android.view.Menu;import android.view.View;import android.widget.AdapterView;import android.widget.AdapterView.OnItemSelectedListener;import android.widget.ArrayAdapter;import android.widget.Spinner;import android.widget.Toast;/** * 通过继承OnItemSelectedListener接口来实现选择时的事件 * @author xuliugen * */public class MainActivity extends Activity implements OnItemSelectedListener { private Spinner spinner1; private Spinner spinner2; // private SpinnerAdapter spinnerAdapter; private ArrayAdapter<String> adapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); spinner1 = (Spinner) this.findViewById(R.id.spinner1); spinner2 = (Spinner) this.findViewById(R.id.spinner2); // 第一种手工输入的list adapter = new ArrayAdapter<String>(MainActivity.this,  android.R.layout.simple_spinner_item, getDataSource()); spinner1.setAdapter(adapter); //注册监听器 spinner1.setOnItemSelectedListener(this); // 第二种：通过加载xml文件配置的数据源 ArrayAdapter adapter2 = ArrayAdapter.createFromResource(this,  R.array.planets_array, android.R.layout.simple_spinner_item); adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); spinner2.setAdapter(adapter2); } /* * 通过第一种方法：手工输入的list */ public List<String> getDataSource() { List<String> list = new ArrayList<String>(); list.add("beijing"); list.add("beida"); list.add("shahai"); list.add("shangjing"); list.add("shanglian"); list.add("chengdu"); return list; } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main, menu); return true; } @Override public void onItemSelected(AdapterView<?> parent, View view, int position,  long id) { String itemString = spinner1.getItemAtPosition(position).toString(); Toast.makeText(this, "你选中的是" + itemString, 1).show(); } @Override public void onNothingSelected(AdapterView<?> parent) { }}

<?xml version="1.0" encoding="utf-8"?><resources>  <string name="app_name">Spinners</string>  <string name="action_settings">Settings</string>  <string name="hello_world">Hello world!</string>  <string-array name="planets_array">    <item>Mercury</item>    <item>Venus</item>    <item>Earth</item>    <item>Mars</item>    <item>Jupiter</item>    <item>Saturn</item>    <item>Uranus</item>    <item>Neptune</item>  </string-array></resources>