StorageUtils.java

package com.matsuhiro.android.storage;

import android.os.Environment;
import android.os.StatFs;

public class StorageUtils {

	@SuppressWarnings("deprecation")
	public static long getAvailableStorage() {

        String storageDirectory = null;
        storageDirectory = Environment.getExternalStorageDirectory().toString();

        try {
            StatFs stat = new StatFs(storageDirectory);
            long avaliableSize = ((long) stat.getAvailableBlocks() * (long) stat.getBlockSize());
            return avaliableSize;
        } catch (RuntimeException ex) {
            return 0;
        }
    }

}