Android 之 Spinner用法介绍

布局文件：

<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" >

    <Spinner
        android:id="@+id/myspinner"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

</RelativeLayout>

主程序入口

package com.sun.spinner;

import android.app.Activity;
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.Toast;

public class MainActivity extends Activity {

	// 显示的条目内容
	private static final String[] m_arr = { "第一组", "第二组", "第三组" };

	// 程序入口
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		spinner();
	}

	// spinner 效果实现
	public void spinner(){
		Spinner spinner = (Spinner) findViewById(R.id.myspinner);
		spinner.setPrompt("请选择颜色"); // 提示标题
		
		// 使用数组适配器进行填充
		ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.spinnercolor, android.R.layout.simple_spinner_item);
		//ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_spinner_item,m_arr);
		
		// 下拉的样式
		adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
		spinner.setAdapter(adapter);
		spinner.setSelection(0, true); // 默认选择 -- 第一项
		
		spinner.performClick(); //它被定义就调用此视图的OnClickListener（译者注：例如可以在加载时默认弹出下拉列表）
		
		spinner.setOnItemSelectedListener(new OnItemSelectedListener() {

			public void onItemSelected(AdapterView<?> arg0, View arg1,
					int arg2, long arg3) {
				
				Toast.makeText(MainActivity.this, "选择了："+getResources().getStringArray(R.array.spinnercolor)[arg2],1000).show();
			}

			@Override
			public void onNothingSelected(AdapterView<?> arg0) {
				// TODO Auto-generated method stub
				
			}
		});
	}
	
	

}