Android读取SD卡下面所有的TXT文件名 listView显示出来

package com.zxl;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class Txt_sdkaActivity extends Activity {
private ListView lv;
ArrayList name;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
lv = (ListView) findViewById(R.id.lv);
name = new ArrayList();
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
File path = Environment.getExternalStorageDirectory();// 获得SD卡路径
// File path = new File("/mnt/sdcard/");
File[] files = path.listFiles();// 读取
getFileName(files);
}
SimpleAdapter adapter = new SimpleAdapter(this, name, R.layout.pes, new String[] { "Name" }, new int[] { R.id.txt_tv });
lv.setAdapter(adapter);
for (int i = 0; i < name.size(); i++) {
Log.i("zeng", "list.  name:  " + name.get(i));
}
}

private void getFileName(File[] files) {
if (files != null) {// 先判断目录是否为空，否则会报空指针
for (File file : files) {
if (file.isDirectory()) {
Log.i("zeng", "若是文件目录。继续读1" + file.getName().toString() + file.getPath().toString());

getFileName(file.listFiles());
Log.i("zeng", "若是文件目录。继续读2" + file.getName().toString() + file.getPath().toString());
} else {
String fileName = file.getName();
if (fileName.endsWith(".txt")) {
HashMap map = new HashMap();
String s = fileName.substring(0, fileName.lastIndexOf(".")).toString();
Log.i("zeng", "文件名txt：：   " + s);
map.put("Name", fileName .substring(0, fileName.lastIndexOf(".")));
name.add(map);
}
}
}
}
}
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello" />

<ListView
android:id="@+id/lv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/textView1"
android:layout_marginTop="62dp" >
</ListView>

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<TextView
android:id="@+id/txt_tv"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textSize="20pt"
android:layout_weight="1"
/>

</LinearLayout>