File file=new File(path);

File[] files = file.listFiles();

for (File currentFile : files)
{
  //判断是一个文件夹还是一个文件
  if (currentFile.isDirectory())
  {
    currentIcon = getResources().getDrawable(R.drawable.folder);
  }
  else
  {
    //取得文件名
    String fileName = currentFile.getName();
    //根据文件名来判断文件类型，设置不同的图标
    if (checkEndsWithInStringArray(fileName, getResources().getStringArray(R.array.fileEndingImage)))
    {
      currentIcon = getResources().getDrawable(R.drawable.image);
    }
    else if (checkEndsWithInStringArray(fileName, getResources().getStringArray(R.array.fileEndingWebText)))
    {
      currentIcon = getResources().getDrawable(R.drawable.webtext);
    }
    else if (checkEndsWithInStringArray(fileName, getResources().getStringArray(R.array.fileEndingPackage)))
    {
      currentIcon = getResources().getDrawable(R.drawable.packed);
    }
    else if (checkEndsWithInStringArray(fileName, getResources().getStringArray(R.array.fileEndingAudio)))
    {
      currentIcon = getResources().getDrawable(R.drawable.audio);
    }
    else if (checkEndsWithInStringArray(fileName, getResources().getStringArray(R.array.fileEndingVideo)))
    {
      currentIcon = getResources().getDrawable(R.drawable.video);
    }
    else
    {
      currentIcon = getResources().getDrawable(R.drawable.text);
    }
  }
}

//通过文件名判断是什么类型的文件
private boolean checkEndsWithInStringArray(String checkItsEnd, String[] fileEndings)
{
    for(String aEnd : fileEndings)
    {
      if(checkItsEnd.endsWith(aEnd))
        return true;
    }
    return false;
}