统计目录大小和时间删除早期的大文件
为什么要做这些，等你需要的时候你就知道了
private void deleteOldestFile(File directory){File[] files = directory.listFiles();Arrays.sort(files, new Comparator<File>() { ? ? @Override? ? public int compare(File f1, File f2) ? ? { ? ? ? ? ? ? ? return Long.valueOf(f1.lastModified()).compareTo(f2.lastModified()); ? ? ? ?? ? }});files[0].delete();?}private static long dirSize(File dir) {long result = 0;File[] fileList = dir.listFiles();for(int i = 0; i < fileList.length; i++) {? ? if(fileList[i].isDirectory()) {? ? ? ? result += dirSize(fileList [i]);? ? } else {? ? ? ? // Sum the file size in bytes? ? ? ? result += fileList[i].length();? ? }?}return result; }File dirlist = new File(Environment.getExternalStorageDirectory() + "/VideoList");if(!(dirlist.exists()))dirlist.mkdir();Long directorySize = dirSize(dirlist);?if (directorySize > 1073741824) // this is 1GB in bytes?{? ? deleteOldestFile(dirlist); ?}File TempFile = new File(Environment.getExternalStorageDirectory() ? ? ? ? ? ? ? ? + "/VideoList", dateFormat.format(date) + fileFormat);mediaRecorder.setOutputFile(TempFile.getPath());while (directorySize > 1073741824){? deleteOldestFile(dirlist);? direcotrySize = dirSize(dirlist);}