Android用ListView显示SDCard文件列表

package com.zy;

import java.io.File;
import java.util.LinkedList;
import java.util.List;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class FileListAdapter extends BaseAdapter {

public Activity activity; //创建View时必须要提供Context
public List<File> list=new LinkedList<File>(); //数据源           list 接口 Lnk 实现接口的类
public String currPath;

public FileListAdapter(Activity activity) {
this.activity = activity;
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return list.size();
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return null;
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(int pos, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub

View v=View.inflate(activity, R.layout.item, null);

TextView txtName= (TextView) v.findViewById(R.id.txtname);
ImageView imgIcon=(ImageView) v.findViewById(R.id.imageView1);

File f=list.get(pos);

txtName.setText(f.getName());

Bitmap bmp_folder=BitmapFactory.decodeResource(
activity.getResources(),R.drawable.folder);
Bitmap bmp_file=BitmapFactory.decodeResource(
activity.getResources(),R.drawable.file);
if(f.isDirectory())
imgIcon.setImageBitmap(bmp_folder);
else
imgIcon.setImageBitmap(bmp_file);
return v;
}

public void scanFiles(String path) {
// TODO Auto-generated method stub
list.clear();

File dir=new File(path);
File[] subFiles=dir.listFiles();
if(subFiles!=null)
for(File f:subFiles)
list.add(f);
this.notifyDataSetChanged();
currPath=path;

}

}

package com.zy;

import java.io.File;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;

public class FileList13Activity extends Activity implements OnItemClickListener, OnClickListener {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
getObjFromID();//获取3个对象

FileListAdapter da=new FileListAdapter(this);
lv.setAdapter(da);
lv.setOnItemClickListener(this);
da.scanFiles("/");

btnUp.setOnClickListener(this);
}

ListView lv;
TextView t1;
Button btnUp;

void getObjFromID()
{
t1=(TextView) findViewById(R.id.txt);
lv=(ListView) findViewById(R.id.listView1);
btnUp=(Button) findViewById(R.id.btnup);
}

@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
FileListAdapter da= (FileListAdapter) lv.getAdapter();
File f= da.list.get(arg2);
if(f.isDirectory())
{
t1.setText(f.getPath());
da.scanFiles(f.getPath());
}
}

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
FileListAdapter da= (FileListAdapter) lv.getAdapter();
if(da.currPath.equals("/")) return;
File f=new File(da.currPath);
t1.setText(f.getParent());
da.scanFiles(f.getParent());

}

}