Android block ads in webview

Question

I want to implement a mechanism in a custom webview client (without JavaScript injection) that can block ads. Is a way I can catch ads and replace them with other ads from a

Answer 1

I made a custom WebViewClient like:

public class MyWebViewClient extends WebViewClient {

    @Override
    public void onPageFinished(WebView view, String url) { }

    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        if (url.endsWith(".mp4")) {
            Intent intent = new Intent(Intent.ACTION_VIEW);
            intent.setDataAndType(Uri.parse(url), "video/*");
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            view.getContext().startActivity(intent);
            return true;
        } else if (url.startsWith("tel:") || url.startsWith("sms:") || url.startsWith("smsto:")
                || url.startsWith("mms:") || url.startsWith("mmsto:")) {
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            view.getContext().startActivity(intent);
            return true;
        } else {
            return super.shouldOverrideUrlLoading(view, url);
        }
    }

    private Map loadedUrls = new HashMap<>();

    @SuppressWarnings("deprecation")
    @Override
    public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
        boolean ad;
        if (!loadedUrls.containsKey(url)) {
            ad = AdBlocker.isAd(url);
            loadedUrls.put(url, ad);
        } else {
            ad = loadedUrls.get(url);
        }
        return ad ? AdBlocker.createEmptyResource() :
                super.shouldInterceptRequest(view, url);
    }
}

And created an AdBlocker class like:

public class AdBlocker {
private static final Set AD_HOSTS = new HashSet<>();

public static boolean isAd(String url) {
    try {
        return isAdHost(getHost(url));
    } catch (MalformedURLException e) {
        Log.e("Devangi..", e.toString());
        return false;
    }
}

private static boolean isAdHost(String host) {
    if (TextUtils.isEmpty(host)) {
        return false;
    }
    int index = host.indexOf(".");
    return index >= 0 && (AD_HOSTS.contains(host) ||
            index + 1 < host.length() && isAdHost(host.substring(index + 1)));
}

public static WebResourceResponse createEmptyResource() {
    return new WebResourceResponse("text/plain", "utf-8", new ByteArrayInputStream("".getBytes()));
}

public static String getHost(String url) throws MalformedURLException {
    return new URL(url).getHost();
}

}

And use this WebViewClient in your oncreate like:

 webview.setWebViewClient(new MyWebViewClient());