也发一个自己实现的android简单文件选择器代码。支持多卡，排序

　　一个很简单的文件选择器对话框，支持双sd卡，当然前提是要有sd卡。。并且实现了排序效果.

只有100多行的代码，基本的思路就是用listview显示目录下的所有子文件，再判断是文件还是目录。

利用Collections.sort方法进行排序。

代码如下:

package net.yunstudio.demo;

import java.io.File;
import java.text.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;


import android.app.Dialog;
import android.content.Context;
import android.os.Environment;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class FilePickerDialog extends Dialog implements OnItemClickListener{

    public FilePickerDialog(Context context) {
        super(context);
        init();
    }
    
    
    private ListView lv_file;
    private SimpleAdapter simpleAdapter;
    private List<Map<String, Object>> dataList;
    private OnFileSelectListener listener;
    //通过获取sd卡的父级，可以兼容双sd卡的情况
    private static final File rootPath=
            Environment.getExternalStorageDirectory().getParentFile(); 
    
    private static final String SRC="src"; 
    private static final String NAME="name";
    private static final String FILE="file";
    private static final String IS_BAK="isBak";
    
    private void init() {
        getChildren2dataList(rootPath);
        simpleAdapter=new SimpleAdapter(getContext(),dataList , R.layout.list_item_choosefile, 
                new String[]{SRC,NAME}, new int[]{R.id.iv_file_type,R.id.tv_file_name});
        
        lv_file=new ListView(getContext());
        lv_file.setAdapter(simpleAdapter);
        lv_file.setOnItemClickListener(this);
        setContentView(lv_file);
        
        setCanceledOnTouchOutside(true);
        this.setTitle("请选择文件");
    }
    /**
     * 设置选择文件的监听器
     * @param listener
     */
    public void setOnFileSelectListener(OnFileSelectListener listener) {
        this.listener = listener;
    }
    /**
     * 将本目录的子文件的信息赋值给dataList字段
     * @param dir
     */
    private void getChildren2dataList(File dir) {
        File[] children=dir.listFiles();
        if(dataList==null){
            dataList=new ArrayList<Map<String,Object>>();
        }else {
            dataList.clear();
        }    
        
        if(!rootPath.equals(dir)){
            Map<String, Object> map=new HashMap<String, Object>();
            map.put(SRC, R.drawable.folder);
            map.put(NAME, "..");
            map.put(FILE, dir.getParentFile());
            map.put(IS_BAK, true);
            dataList.add(map);
        }
        if(children==null) return ;//避免空目录引起的空指针错误
        for (File file : children) {
            Map<String, Object> map=new HashMap<String, Object>();
            map.put(SRC, file.isDirectory()
                                ?R.drawable.folder
                                :R.drawable.file);
            map.put(NAME, file.getName());
            map.put(FILE, file);
            dataList.add(map);
        }
        
        
        Collections.sort(dataList, new Comparator<Map<String, Object>>() {

            @Override
            public int compare(Map<String, Object> lhs, Map<String, Object> rhs) {
                int result=0;
                
                if(lhs.get(IS_BAK)!=null){
                    result = -1;
                }else if (rhs.get(IS_BAK)!=null) {
                    result = 1;
                }else {
                    File lhsFile=(File) lhs.get(FILE);
                    File rhsFile=(File) rhs.get(FILE);  
                    
                    if(lhsFile.isDirectory()&&rhsFile.isFile()){
                        result = -1;
                    }else if (lhsFile.isFile()&&rhsFile.isDirectory()) {
                        result = 1;
                    }else {
                        Collator cmp = Collator.getInstance(Locale.getDefault());  
                        result = cmp.compare(lhs.get(NAME), rhs.get(NAME));
                    }
                }
                return result;
            }
        });
    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {
        File file=(File)dataList.get(position).get(FILE);
        if(file.isDirectory()){
            getChildren2dataList(file);
            simpleAdapter.notifyDataSetChanged();
        }else {
            if(listener!=null){
                listener.onFileSelect(file);
                this.dismiss();
            }
        }
    }
    
    public static interface OnFileSelectListener{
        void onFileSelect(File file);
    }
}

项目下载地址:点击下载