Returns the HTML for the captcha question and answer.
Used in __toString() and to be used when $data['captchaRender'] is set to false. It is not called when the element is frozen, see getFrozenHtml() for that case. This method is also not called when the captcha has been solved, since $data['captchaSolved'] is shown then.
Overrides
HTML_QuickForm2_Element_Captcha::getCaptchaHtml() (Returns the HTML for the captcha (question + input element if applicable))
Checks if the captcha is solved now.
Uses $capSolved variable or user input, which is compared with the pre-set correct answer.
Calls generateCaptcha() if it has not been called before.
In case user solution and answer match, a session variable is set so that the captcha is seen as completed across form submissions.
Overrides
HTML_QuickForm2_Element_Captcha::verifyCaptcha() (Checks if the captcha is solved now.)