ReCaptcha Add-on for Vaadin 7

Vaadin-recaptcha is a wrapper component for ReCaptcha v2. See http://www.google.com/recaptcha

Online demo

Try the add-on demo at http://demo.webstar.hu/vaadin-recaptcha

Usage

1. Create your keys at http://www.google.com/recaptcha

2. Create, and add the component to your UI

   ReCaptcha captcha = new ReCaptcha(
       your_private_key,
       new ReCaptchaOptions() {{//your options
           theme = "light";
           sitekey = your public_key;
       }}
   );
   layout.addComponent(captcha);
   

3. Validate somewhere in an event handler

   if (!captcha.validate()) {
       Notification.show("Invalid!", Notification.Type.ERROR_MESSAGE);
       captcha.reload();
   } else {
       //do your job
   }
   

See DummyRegWithReCaptcha.java

Documentation

For ReCaptcha options see: https://developers.google.com/recaptcha/docs/display#render_param. For Language codes see: https://developers.google.com/recaptcha/docs/language

Known Issues and limitations

1. The racaptha api renders with javascript using ajax after page load. It means the component becames visible after everything is rendered, with flickering, and layout repaint. To avoid this you can fix the size from css, or put the component into a fixed size parent.

2. The javascript api does not support more recaptcha on one page.

3. The javascript api does not suport changing options (like theme, or language) on the same page. Once a component is rendered, all other components inherit the options, until page reload.