static void setLogin(final String username, final String password) {
        if (StringUtils.isBlank(username) || StringUtils.isBlank(password)) {
            // erase username and password
            remove(R.string.pref_username);
            remove(R.string.pref_password);
            return;
        }
        // save username and password
        putString(R.string.pref_username, StringUtils.trim(username));
        putString(R.string.pref_password, password);
    }
Force set the plain text log preference

@param plainLogs wanted or not
main/src/main/java/cgeo/geocaching/settings/Settings.java