[SalesForce] How to use StandardController from visualforce Component

You only get "one bite at the cherry" with the Standard Controller. But If you can afford to put the markup in the entry point page, this may be worth noting:

• apex:include targets cannot traverse standard controllers
• but apex:composition defines can traverse included pages

Fields can only be queried automatically via a StandardController on an apex:page. Even though apex:include is unavilable in apex:component, you can cheat by moving your component body to a page, then doing a poor-man's include (parameterized PageReference.getContent) from the component controller.

Then, communicate the Campaign Id into your component so it can be requeried. Here's an example:

• the Campaign Name is queried from the Page
• the Campaign Status is queried from the Component

CustomCampaign.page

<apex:page standardController="Campaign">
  <apex:sectionHeader title="{!Campaign.Name}" />
  <c:importCampaign campaignId="{!Id}" />
</apex:page>

ImportCampaign.component

<apex:component controller="ImportCampaignController">
  <apex:attribute name="campaignId" type="Id" description="Id" assignTo="{!IdParam}" />
  <apex:outputText escape="false" value="{!Include}" />
</apex:component>

ImportCampaignController.cls

public class ImportCampaignController {

  public Id IdParam {get; set;}

  public String getInclude() {
    System.PageReference pageReference = Page.ImportCampaignBody;
    pageReference.getParameters().put('id', this.IdParam);
    return pageReference.getContent().toString();
  }

}

ImportCampaignBody.page

<apex:page standardController="Campaign">
  <apex:sectionHeader title="Status: {!Campaign.Status}" />
</apex:page>

(special thanks to Andrew Fawcett for sanity checking and analyzing this and multiple other approaches)

You shouldn't be able to add a page to a layout without the standardController entity matching the layout's entity. It sounds like a bug in your DE org.

You should indeed use the standardController attribute on your page, and I would further recommend passing the standard controller to the component instead of grabbing the ID parameter. I use a class that looks (almost exactly) like this:

public with sharing class StandardController {
    public ApexPages.StandardController standardController { get; set; }
    public StandardController(ApexPages.StandardController standardController) {
        this.standardController = standardController;
    }
}

It's used in a page like this:

<apex:page standardController="Account" extensions="StandardController">
    <c:myComponent standardController="{!standardController}"/>
</apex:page>

Most of my components therefore use custom getter/setter methods, since it reduces my component's constructor to uselessness, but I consider it a worthy sacrifice, as I can then access the standard controller's PageReference's directly, such as cancel, view, and save.

public with sharing class myCompController {
    public ApexPages.StandardController controller {
        get; set {
            if(controller!=null) return;
            // do my component initialization here.
        }
    }
}

The standardController method works in all types of orgs. Not providing a standardController attribute is not supported and shouldn't work, so you should never rely on it working.