@Override
        public boolean onNavigationAttempt(String url) {
            // Give plugins the chance to handle the url
            if (pluginManager.onOverrideUrlLoading(url)) {
                return true;
            } else if (pluginManager.shouldAllowNavigation(url)) {
                return false;
            } else if (pluginManager.shouldOpenExternalUrl(url)) {
                showWebPage(url, true, false, null);
                return true;
            }
            LOG.w(TAG, "Blocked (possibly sub-frame) navigation to non-allowed URL: " + url);
            return true;
        }