android怎么获取一个文件的地址

跟java里获取当前本地文件、文件夹，，点击文件夹，显示该文件夹下的文件和文件夹，是没有区别的啊，唯一就是在文件夹上添加监听事件，然后获取对象就是了……

activity ：
package com.hundsun.zhoujl.android;

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

import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.DialogInterface;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class Test_fileActivity extends ListActivity {

private ArrayList items = null;

private ArrayList paths = null;

private String rootPath = "/";

private TextView mPath;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

mPath = (TextView)findViewById(R.id.mPath);

mPath.setTextColor(Color.RED);

getFileDir(rootPath);

}

private void getFileDir(String filePath) {

mPath.setText(filePath);

items = new ArrayList();

paths = new ArrayList();

File file = new File(filePath);

File[] files = file.listFiles();

if(!filePath.equals(rootPath)) {

items.add("Back To " + rootPath);

paths.add(rootPath);

items.add("Back to ../");

paths.add(file.getParent());

}

for(File fileTemp :files) {

items.add(fileTemp.getName());

paths.add(fileTemp.getPath());

}

ArrayAdapter adapter = new ArrayAdapter(Test_fileActivity.this,R.layout.file_now,items);

setListAdapter(adapter);

}

@Override

protected void onListItemClick(ListView l, View v, int position, long id) {

File file = new File(paths.get(position));

if(file.canRead()) {

if(file.isDirectory()) {

getFileDir(paths.get(position));

}else {

new AlertDialog.Builder(this)

.setTitle("Message")

.setMessage("["+file.getName() + "] is a file")

.setPositiveButton("ok", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

}

}).show();

}

}else {

new AlertDialog.Builder(this)

.setTitle("Message")

.setMessage("权限不足~")

.setPositiveButton("ok", new DialogInterface.OnClickListener() {

@Override

public void onClick(DialogInterface dialog, int which) {

}

}).show();

}

}

}
main.xml:

android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>

android:id="@android:id/list"

android:layout_width="fill_parent"

android:layout_height="wrap_content"
>




file_now.xml

xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="20px"
android:textSize="14sp"
>