/* 判斷SD卡是否存在 返回true表示存在 */
public boolean avaiableMedia() {
  String status = Environment.getExternalStorageState();
  if (status.equals(Environment.MEDIA_MOUNTED)) {
   return true;
  } else {
   return false;
  }
}

/* 獲取SD卡可用空間 */
public long getSDFreeSize() {
  // 取得SD卡文件路徑
  File path = Environment.getExternalStorageDirectory();
  StatFs sf = new StatFs(path.getPath());
  // 獲取單個數(shù)據(jù)塊的大小(Byte)
  long blockSize = sf.getBlockSizeLong();
  // 空閑的數(shù)據(jù)塊的數(shù)量
  long freeBlocks = sf.getAvailableBlocksLong();
  // 返回SD卡空閑大小
  // return freeBlocks * blockSize; //單位Byte
  // return (freeBlocks * blockSize)/1024; //單位KB
  return (freeBlocks * blockSize) / 1024 / 1024; // 單位MB
}

/* 獲取SD卡所有空間 */
public long getSDAllSize() {
  // 取得SD卡文件路徑
  File path = Environment.getExternalStorageDirectory();
  StatFs sf = new StatFs(path.getPath());
  // 獲取單個數(shù)據(jù)塊的大小(Byte)
  long blockSize = sf.getBlockSizeLong();
  // 獲取所有數(shù)據(jù)塊數(shù)
  long allBlocks = sf.getBlockCountLong();
  // 返回SD卡大小
  // return allBlocks * blockSize; //單位Byte
  // return (allBlocks * blockSize)/1024; //單位KB
  return (allBlocks * blockSize) / 1024 / 1024; // 單位MB
}