Android學習筆記之Spinner下拉列表使用案例

（1）兩種方法提沖Spinner中的數據源：通過list集合，或者是通過xml文件進行配置

（2）布局代碼如下：

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;
/**
 * 通過繼承OnItemSelectedListener接口來實現選擇時的事件
 * @author xuliugen
 *
 */
public class MainActivity extends Activity implements OnItemSelectedListener {

	private Spinner spinner1;
	private Spinner spinner2;
	// private SpinnerAdapter spinnerAdapter;

	private ArrayAdapter 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);

		// 第一種手工輸入的list
		adapter = new ArrayAdapter(MainActivity.this,
				android.R.layout.simple_spinner_item, getDataSource());
		spinner1.setAdapter(adapter);

		//注冊監聽器
		spinner1.setOnItemSelectedListener(this);
		// 第二種：通過加載xml文件配置的數據源
		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);
	}

	/*
	 * 通過第一種方法：手工輸入的list
	 */
	public List getDataSource() {
		List list = new ArrayList();
		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, 你選中的是 + itemString, 1).show();
	}

	@Override
	public void onNothingSelected(AdapterView parent) {

	}

}

（4）資源文件中的配置如下：

    Spinners
    Settings
    Hello world!

    
        Mercury
        Venus
        Earth
        Mars
        Jupiter
        Saturn
        Uranus
        Neptune