//1.获取内存可用大小,内存路径
  String path=Environment.getDataDirectory().getAbsolutePath();
  String memoryAvaliSpace= Formatter.formatFileSize(this,getAvailSpace(path));
  //2.获取sd卡可用大小，sd卡路径
  String sdPath=Environment.getExternalStorageDirectory().getAbsolutePath();
  String sdAvaliSpace= Formatter.formatFileSize(this,getAvailSpace(sdPath));

private long getAvailSpace(String path) {
  //获取可用内存大小
  StatFs statfs=new StatFs(path);
  //获取可用区块的个数
  long count=statfs.getAvailableBlocks();
  //获取区块大小
  long size=statfs.getBlockSize();
  //可用空间总大小
  return count*size;
 }