A Visualforce page can be embedded into a standard or custom sObject record view page, providing the standard controller for the sObject type manages it. This technique is often used to allow information to be added to a record or its related lists without leaving the view page. The Visualforce page is embedded in the record view page using an iframe. This means that returning a page reference to send the user to the record view page after an update results in the entire record view page being displayed inside the iframe, as shown in the following screenshot:
In this recipe, we will create a Visualforce page that is embedded inside the standard case sObject record view page and allows a case comment to be added directly from the page. Upon saving a case comment, the entire record view page will be refreshed to display the updated case comments related list.