Can I edit the text of sign in button on Google?

Here is the technique that I used:

protected void setGooglePlusButtonText(SignInButton signInButton, String buttonText) {
    // Find the TextView that is inside of the SignInButton and set its text
    for (int i = 0; i < signInButton.getChildCount(); i++) {
        View v = signInButton.getChildAt(i);

        if (v instanceof TextView) {
            TextView tv = (TextView) v;
            tv.setText(buttonText);
            return;
        }
    }
}