Remote Methods and Inheritance

You can call remote actions on your Apex controller that are inherited methods. When a @RemoteAction method is looked up or called, Visualforce inspects the page controller’s inheritance hierarchy and finds @RemoteAction methods in the controller’s ancestor classes.

Here’s an example demonstrating this capability. The following Apex classes form a three-tier inheritance hierarchy:

global with sharing class ChildRemoteController 
    extends ParentRemoteController { }
global virtual with sharing class ParentRemoteController 
    extends GrandparentRemoteController { }

global virtual with sharing class GrandparentRemoteController {
    @RemoteAction
    global static String sayHello(String helloTo) {
        return 'Hello ' + helloTo + ' from the Grandparent.';
    }
}

This Visualforce page simply calls the sayHello remote action.

<apex:page controller="ChildRemoteController" >
    <script type="text/javascript">
        function sayHello(helloTo) {
            ChildRemoteController.sayHello(helloTo, function(result, event){
                if(event.status) {
                    document.getElementById("result").innerHTML = result;
                }
            });
        }
    </script>

    <button onclick="sayHello('Jude');">Say Hello</button><br/>
    <div id="result">[Results]</div>
    
</apex:page>

The remote method doesn’t exist in the ChildRemoteController class. Instead, it’s inherited from GrandparentRemoteController.