An Example of Using Remote Method Overrides in Remote Objects

This sample code illustrates how to create remote method overrides for Remote Objects operations. The example presents a sorted list of contacts and a simple form to enter a new contact. The new contact action overrides the built-in Remote Objects create() operation. The sample also illustrates blending Remote Objects with several Web development libraries to present a mobile-friendly user interface.

This example uses the jQuery, Bootstrap, and Mustache tool kits, loading them from an external content distribution network (CDN). An example of a contact form using Visualforce Remote Objects

Here’s the Visualforce page, with the remote override declaration in bold.

The key line of code in the preceding sample is in the Remote Objects access definition. Adding a single attribute to the contact Remote Object definition sets up the override:

The attribute takes a Visualforce expression that references the @RemoteAction method to use as the override for the built-in create() operation.

In this case, the referenced method is in an Apex class that’s the page’s controller. The code for the override method is straightforward.

This method logs the @RemoteAction call and then uses the standard RemoteObjectController.create() call to perform the create. It’s performing the same data manipulation language (DML) commands to create the record that the built-in version would, because it’s using the built-in version. After performing the create, the method does a little more logging. Finally it adds some extra data to the return payload that will be received by the JavaScript callback function on the Visualforce page.

It’s adding the extra data that’s interesting and makes overriding the built-in method useful. The extra data that’s added by the preceding controller is trivial, for the purposes of illustration only. A real-world override can include more complex logic—the result of a calculation, other method calls, and so on. What’s important to understand is that the new custom override method can do additional things behind the scenes, and can return extra data that the built-in version can’t.

Visualforce Developer’s Guide

An Example of Using Remote Method Overrides in Remote Objects