Generate Facebook KeyHash Android Programatically

FacebookKeyHash

 @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        try {
            PackageInfo info = getPackageManager().getPackageInfo(
                    "com.facebook.samples.loginhowto", 
                    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 (NameNotFoundException e) {

        } catch (NoSuchAlgorithmException e) {

        }
        ...other operations

}//end of onCreate