Call it in Activity.onCreate to see facebook debug key hash

gistfile1.txt

  /**
     * Call it in Activity.onCreate to see facebook debug key hash
     *
     * @param activity
     */
    public static void logFbKeyHash(Activity activity) {
        try {
            PackageInfo info = activity.getPackageManager().getPackageInfo(
                    activity.getPackageName(),
                    PackageManager.GET_SIGNATURES);
            for (Signature signature : info.signatures) {
                MessageDigest md = MessageDigest.getInstance("SHA");
                md.update(signature.toByteArray());
                Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT));
            }
        } catch (Exception e) {
            Log.e("logFbKeyHash", "", e);
        }
    }