android--UI--spinner

package com.example.spinner;

import android.os.Bundle;
import android.app.Activity;
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;

public class MainActivity extends Activity implements OnItemSelectedListener{
    
    private Spinner spinner2,spinner3;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        spinner2=(Spinner) findViewById(R.id.spinner02);
        //註冊事件
        spinner2.setOnItemSelectedListener(this);
        String[] citys=getResources().getStringArray(R.array.citys);
        //創建數組適配器---給spinner與數組進行適配
        ArrayAdapter<String> adapter=new ArrayAdapter<String>(this,android.R.layout.simple_spinner_dropdown_item, citys);        
        spinner2.setAdapter(adapter);
        
        spinner3=(Spinner) findViewById(R.id.spinner03);
        ArrayAdapter<CharSequence> adapter3=ArrayAdapter.createFromResource(this,R.array.citys,android.R.layout.simple_list_item_1 );
        //adapter3.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        //自定義樣式
        adapter3.setDropDownViewResource(R.layout.spinner_item);
        spinner3.setAdapter(adapter3);
        
    }
    @Override
    public void onItemSelected(AdapterView<?> perent, View v, int pos,
            long id) {
        System.out.println(perent.getClass());//spinner
        System.out.println(v.getClass());//CheckedTextView
        System.out.println("pos="+pos);//位置
        System.out.println("id="+id);//序號
        //spinner.getSelectedItem() 獲取下拉列表中選中的值
        Toast.makeText(this,spinner2.getSelectedItem().toString(),Toast.LENGTH_LONG).show();
    }

}

string.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">Spinner</string>
    <string name="action_settings">Settings</string>
    <string name="hello_world">Hello world!</string>
    
    <string-array name="citys">
        <item>北京</item>
        <item>上海</item>
        <item>廣州</item>
        <item>成都</item>
    </string-array>
</resources>

自定義樣式<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@android:id/text1"
    android:textColor="#00ff00"
    android:textSize="20sp">
    
</TextView>