安卓自定义Spinner 样式

<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"
    tools:context="${packageName}.${activityClass}" >
    <Spinner
        android:id="@+id/sp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/text1"
    
    android:layout_width="match_parent"
    android:layout_height="40sp"
    android:textSize="30sp"
    android:background="#FFFFFF"
    android:singleLine="true" />

import android.app.Activity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

public class MainActivity extends Activity {
	
	Spinner spinner;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		spinner=(Spinner)findViewById(R.id.sp);
		
		String data[]=new String[]{"a","b","c"};
		//声明一个ArrayAdaper，用来装载Spinner数据
		ArrayAdapter<String>adapter=new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, data);
		//加载item的布局样式
		adapter.setDropDownViewResource(R.layout.spitem);
		//最后让Spinner加载adapter
		spinner.setAdapter(adapter);
	}
}