Android Spinner 组件的应用实例

    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  xmlns:tools="http://schemas.android.com/tools" 
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent" 
  android:orientation="vertical"   
 
  <ScrollView 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content"   
 
    <LinearLayout 
      android:layout_width="fill_parent" 
      android:layout_height="fill_parent" 
      android:gravity="center_horizontal" 
      android:orientation="vertical"   
 
      <Spinner 
        android:id="@+id/spinner" 
        android:layout_width="300dp" 
        android:layout_height="wrap_content" 
        android:layout_gravity="center_vertical" /  
 
      <TextView 
        android:id="@+id/showInfo" 
        android:layout_width="fill_parent" 
        android:layout_height="wrap_content" 
        android:layout_marginLeft="15dp" 
        android:layout_marginRight="15dp" 
        android:gravity="center" 
        android:text=" " /  
    </LinearLayout  
  </ScrollView  
 
</LinearLayout  

package com.example.spinnertest; 
import java.util.ArrayList; 
import android.app.Activity; 
import android.content.res.Resources; 
import android.os.Bundle; 
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 Activity { 
private Spinner spinner; 
private TextView tx; 
private ArrayList<String  list = null; 
protected void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.main); 
/* 获取TextView 实体对象 ， 用于显示星座的详细信息 */ 
tx = (TextView) findViewById(R.id.showInfo); 
/* 下拉组件测试 Spinner 对象首先获取 */ 
spinner = (Spinner) findViewById(R.id.spinner); 
/* 准备数据源 M , 用集合进行保存 */ 
list = new ArrayList<String ();  
list.add("Aries"); 
list.add("Taurus"); 
list.add("Gemini"); 
list.add("Cancer"); 
list.add("Leo"); 
list.add("Virgo"); 
list.add("Libra"); 
list.add("Scorpio"); 
list.add("Sagittarius"); 
list.add("Capricorn"); 
list.add("Aquarius"); 
list.add("Pisces"); 
/* 实现M 层 与C 层的关系 ,绑定数据 */ /* 参数1：上下文对象； 参数2：系统资源布局方式 ； 参数3：数据对象 */ 
ArrayAdapter<String  adapter = new ArrayAdapter<String (this, android.R.layout.simple_spinner_dropdown_item, list); 
/* 对V 层和C 层进行关系的绑定； */ 
spinner.setAdapter(adapter); 
spinner.setOnItemSelectedListener(new OnItemSelectedListener() { 
/* 对所有的选择项进行监控 *//* 参3：当前选择项的ID 参4：被选择项在组中的位置，逻辑上与ID 相等，但代表的意义不一样 */ 
public void onItemSelected(AdapterView<?  arg0, View arg1, 
int id, long position) { 
// Toast.makeText(MainActivity.this, "你选择的是第:"+id+"值为："+list.get(id), 1000).show(); 
/* 设置tx对象的值 */ 
String temp = getConstellation(id); 
tx.setText("\t"+temp); 
} 
@Override 
public void onNothingSelected(AdapterView<?  arg0) { 
// TODO Auto-generated method stub 
} 
}); 
} 
/* 显示星座的信息 */ 
protected String getConstellation(int id){ 
Resources rs = getResources(); 
String temp = ""; 
switch(id){ 
case 0: 
temp = rs.getString(R.string.Aries); 
break; 
case 1: 
temp = rs.getString(R.string.Taurus); 
break; 
case 2: 
temp = rs.getString(R.string.Gemini); 
break; 
case 3: 
temp = rs.getString(R.string.Cancer); 
break; 
case 4: 
temp = rs.getString(R.string.Leo); 
break; 
case 5: 
temp = rs.getString(R.string.Virgo); 
break; 
case 6: 
temp = rs.getString(R.string.Libra); 
break; 
case 7: 
temp = rs.getString(R.string.Scorpio); 
break; 
case 8: 
temp = rs.getString(R.string.Sagittarius); 
break; 
case 9: 
temp = rs.getString(R.string.Capricorn); 
break; 
case 10: 
temp = rs.getString(R.string.Aquarius); 
break; 
case 11: 
temp = rs.getString(R.string.Pisces); 
break; 
case 12: 
temp = rs.getString(R.string.Aries); 
break; 
} 
return temp; 
} 
}