Android中Spinner控件之键值对用法实例分析

package com.ljq.activity;
import java.io.Serializable;
@SuppressWarnings("serial")
public class Dict implements Serializable {
 private Integer id;
 private String text;
 public Dict() {
 }
 public Dict(Integer id, String text) {
  super();
  this.id = id;
  this.text = text;
 }
 public Integer getId() {
  return id;
 }
 public void setId(Integer id) {
  this.id = id;
 }
 public String getText() {
  return text;
 }
 public void setText(String text) {
  this.text = text;
 }
 /**
  * 为什么要重写toString()呢？
  * 
  * 因为适配器在显示数据的时候，如果传入适配器的对象不是字符串的情况下，直接就使用对象.toString()
  */
 @Override
 public String toString() {
  return text;
 }
}

package com.ljq.activity;
import java.util.ArrayList;
import java.util.List;
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.Toast;
import android.widget.AdapterView.OnItemSelectedListener;
public class MainActivity extends Activity {
 private Spinner mySpinner;
 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  mySpinner = (Spinner) findViewById(R.id.mySpinner);
  List<Dict> dicts = new ArrayList<Dict>();
  dicts.add(new Dict(1, "测试1"));
  dicts.add(new Dict(2, "测试2"));
  dicts.add(new Dict(3, "测试3"));
  dicts.add(new Dict(4, "测试4"));
  ArrayAdapter<Dict> adapter = new ArrayAdapter<Dict>(this,
    android.R.layout.simple_spinner_item, dicts);
  mySpinner.setAdapter(adapter);
  mySpinner.setOnItemSelectedListener(new OnItemSelectedListener(){
   public void onItemSelected(AdapterView<?> parent, View view,
     int position, long id) {
    // 获取键的方法：mySpinner.getSelectedItem().toString()或((Dict)mySpinner.getSelectedItem()).getId()
    // 获取值的方法：((Dict)mySpinner.getSelectedItem()).getText();
    Toast.makeText(MainActivity.this,
      "键:" + mySpinner.getSelectedItem().toString() + "、" + ((Dict) mySpinner.getSelectedItem()).getId() + 
      "，值:" + ((Dict) mySpinner.getSelectedItem()).getText(),
      Toast.LENGTH_LONG).show();
   }
   public void onNothingSelected(AdapterView<?> parent) {
   }
  });
 }
}

<?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:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:id="@+id/mySpinner"/>
</LinearLayout>