Relationship advice: Many-to-many

Question

So I have a custom object Campaign__c which I need to relate with the Opportunity object. This will be many-to-many, so I've created a junction object called Campaign_plan__c with lookup (also tried M-D) to the other two objects (schema below).

The workflow will be:

• User creates a new "Campaign" record
• User will need to add existing Opportunities to this Campaign
• User should also have the option to create new Opportunities from here, and associate them with the Campaign

What I have so far:

• I've added the Campaign_Plan__c related list to the Campaign__c object, with two custom buttons
• First button "Add Opportunity" takes you to a create new Campaign_Plan__c (junction) record with the Opportunity lookup field, to pick the Opportunity to add
• Second button "Create Opportunities" is a VF page that lets the user create a bunch of Opportunities and save them

Issue(s):

• While the "Create Opportunities" works fine, I'm struggling to pass on the "Campaign" ID or create a Campaign_Plan__c (junction) object record

I tried a trigger, but I'm only able to create a junction object record while creating the Opportunity record and associate with that.

trigger CreateCampPlan on Opportunity (after insert) { List camplan = new List();

for (Opportunity newOpp: Trigger.New) 
    {
        camplan.add(new Campaign_Plan__c(
                    Deal__c = newOpp.Id));
    }
insert camplan;
}

Apex Class and VF to create bulk opportunities

    <apex:page controller="ManageListController" tabstyle="Opportunity">
 <apex:form >
   <apex:pageBlock title="Create associated Deals">
      <apex:pageBlockTable value="{!wrappers}" var="wrapper" id="wtable">
         <apex:column headerValue="Ident">
            <apex:outputText value="{!wrapper.ident}"/>
         </apex:column>
         <apex:column headerValue="Deal Name">
            <apex:inputField value="{!wrapper.opp.Name}"/>
         </apex:column>
         <apex:column headerValue="Account">
            <apex:inputField value="{!wrapper.opp.AccountId}"/>
         </apex:column>
         <apex:column headerValue="Expected Local NOI">
            <apex:inputField value="{!wrapper.opp.Amount}"/>
         </apex:column>
          <apex:column headerValue="Expected Sale Start Date">
            <apex:inputField value="{!wrapper.opp.CloseDate}"/>
         </apex:column>
          <apex:column headerValue="Deal Status">
            <apex:inputField value="{!wrapper.opp.StageName}"/>
         </apex:column>
         <apex:column headerValue="Action">
            <apex:commandButton value="Delete" action="{!delWrapper}" rerender="wtable">
               <apex:param name="toDelIdent" value="{!wrapper.ident}" assignTo="{!toDelIdent}"/> 
            </apex:commandButton>
         </apex:column>
      </apex:pageBlockTable>
      <apex:commandButton value="Add Row" action="{!addRows}" rerender="wtable">
         <apex:param name="addCount" value="1" assignTo="{!addCount}"/> 
      </apex:commandButton>
      <apex:commandButton value="Add 5 Rows" action="{!addRows}" rerender="wtable">
         <apex:param name="addCount" value="5" assignTo="{!addCount}"/> 
      </apex:commandButton>
      <apex:commandButton value="Save" action="{!save}"/>
   </apex:pageBlock>
 </apex:form>
</apex:page>


public class ManageListController 
{
 public List<OpportunityWrapper> wrappers {get; set;}
 public static Integer toDelIdent {get; set;}
 public static Integer addCount {get; set;}
 private Integer nextIdent=0;

 public ManageListController()
 {
  wrappers=new List<OpportunityWrapper>();
  for (Integer idx=0; idx<5; idx++)
  {
   wrappers.add(new OpportunityWrapper(nextIdent++));
  }
 }

 public void delWrapper()
 {
  Integer toDelPos=-1;
  for (Integer idx=0; idx<wrappers.size(); idx++)
  {
   if (wrappers[idx].ident==toDelIdent)
   {
    toDelPos=idx;
   }
  }

  if (-1!=toDelPos)
  {
   wrappers.remove(toDelPos);
  }
 }

 public void addRows()
 {
  for (Integer idx=0; idx<addCount; idx++)
  {
   wrappers.add(new OpportunityWrapper(nextIdent++));
  }
 }

 public PageReference save()
 {
  List<Opportunity> opps=new List<Opportunity>();
  for (OpportunityWrapper wrap : wrappers)
  {
   opps.add(wrap.opp);
  }

  insert opps;

  return new PageReference('/' + Schema.getGlobalDescribe().get('Opportunity').getDescribe().getKeyPrefix() + '/o');
 }

 public class OpportunityWrapper
 {
  public Opportunity opp {get; private set;}
  public Integer ident {get; private set;}

  public OpportunityWrapper(Integer inIdent)
  {
   ident=inIdent;
   opp=new Opportunity(Name='');
  }
 }
}

Any ideas? Let me know if you need more info. As always, thanks so much for your help!

Answer 1

I'd probably make the VF page use the Campaign__c standard controller, that way you can access the Campaign__c record within the extension and therefore associate the new Campaign_Plan__c records with the original Campaign record.

i.e.

<apex:page standardController="Campaign__c" extensions="ManageListController" />

Then in your constructor use:

public class ManageListController 
{
    ....
    private final Campaign__c campy;
    ....
    public ManageListController(ApexPages.StandardController stdController)
    {
        this.campy = (Campaign__c)stdController.getRecord();
        ....
    }
}

By doing this, you have the Campaign__c record and can therefore get the Id.

You could then loop through the Opportunities you've created and add in the Campaign__c records.

public PageReference save()
{
    ....
    insert opps;

    List<Campaign_plan__c> cpToInsert = new List<Campaign_plan__c>();
    for(Opportunity oppy : opps)
    {
        cpToInsert.add(new Campaign_plan__c(Deal__c = oppy.Id, Campaign__c = campy.Id));
    }

    insert cpToInsert;
}

NOTE: This sort of works, although I don't think it works the way you want it to. The button needs to be on the detail of the Campaign__c record rather than the related list.