android 数组数据绑定到listview

package com.zxl;import android.app.ListActivity;import android.os.Bundle;import android.view.View;import android.widget.ArrayAdapter;import android.widget.ListView;import android.widget.Toast;public class MainActivity extends ListActivity {    /** Called when the activity is first created. */    String[] presidentsStrings={    "h",    "o",    "fd",    "fe",    "t",    "h",    "hr",    "fa"    };@Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        //setContentView(R.layout.main);        setListAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,presidentsStrings));    }public void onListItemClick(ListView parent,View v,int position,long id){Toast.makeText(this,"item is "+presidentsStrings[position],Toast.LENGTH_LONG).show();}}