final class MyWebViewClient extends WebViewClient {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
    if (url.endsWith(".mp4") {
        Intent intent = new Intent("android.intent.action.VIEW", Uri.parse(url));
        view.getContext().startActivity(intent);
        return true;
    } else {
        return super.shouldOverrideUrlLoading(view, url);
    }
}