Is it a good practice to nest apex:actionRegion in another apex:actionRegion?

Question

Well I am working on a visualforce page which has several sections with their own fields. The sections should be independent from each other. Now in one section I've got two operations: add and cancel. When I press the Add button I want that only the fields from its section are processed by the server.

However, when I press the Cancel button I don't need to process the section's field - just cancel. It means when cancelling I don't care if the required fields are populated. For this I am certainly need to cover the Cancel button within the apex:actionRegion element.

Here is a part of my code:

<apex:page>

    <apex:form id="recipients">

        <!-- other code is skipped for brevity -->

        <!-- New recepient section -->
        <apex:actionRegion>
            <apex:pageBlock id="addNewRecipient"
                            rendered="{! addNewRecipientVisible }">
                <apex:pageBlockButtons location="bottom">
                    <apex:commandButton value="Add"
                                        action="{! addRecipient }"
                                        reRender="recipients"/>

                    <apex:actionRegion>
                        <apex:commandButton value="Cancel"
                                            action="{! hideAddRecipient }"
                                            immediate="true"
                                            html-formnovalidate="formnovalidate"
                                            reRender="recipients"/>
                    </apex:actionRegion>
                </apex:pageBlockButtons>

                <apex:pageBlockSection columns="1"
                                       title="New recipient">

                    <apex:inputField id="recipientLanguage"
                                    value="{! recipient.Language__c }"/>

                </apex:pageBlockSection>
            </apex:pageBlock>
        </apex:actionRegion>

    </apex:form>

</apex:page>

Notice that there are 2 apex:actionRegion elements which are nested. I ran the code and it worked, but I would like to know if putting apex:actionRegion in another apex:actionRegion is a good practice and it does not have any implications.

Answer 1

I think cancel button within actionRegion is not needed if you don't need to process anything to the server and rerender specific portion. I would prefer not to use nested actionRegion.

Then outer actionRegion is fine for that, no need to use that for cancel.