/**
  * 獲取目錄下所有文件(按時間排序)
  * 
  * @param path
  * @return
  */
 public static List<File> listFileSortByModifyTime(String path) {
  List<File> list = getFiles(path, new ArrayList<File>());
  if (list != null && list.size() > 0) {
   Collections.sort(list, new Comparator<File>() {
    public int compare(File file, File newFile) {
     if (file.lastModified() < newFile.lastModified()) {
      return -1;
     } else if (file.lastModified() == newFile.lastModified()) {
      return 0;
     } else {
      return 1;
     }
    }
   });
  }
  return list;
 }

 /**
  * 
  * 獲取目錄下所有文件
  * 
  * @param realpath
  * @param files
  * @return
  */
 public static List<File> getFiles(String realpath, List<File> files) {
  File realFile = new File(realpath);
  if (realFile.isDirectory()) {
   File[] subfiles = realFile.listFiles();
   for (File file : subfiles) {
    if (file.isDirectory()) {
     getFiles(file.getAbsolutePath(), files);
    } else {
     files.add(file);
    }
   }
  }
  return files;
 }

List<File> list = listFileSortByModifyTime("/storage/sdcard1/DCIM/Camera/");
    int i = 0;
    for (File file : list) {
     i++;
     Log.i("ZMS",
       i + ":" + file.getName() + " = "
         + file.lastModified());
    }