Trouble with after update trigger for Quote Line Item

Question

I am working on a trigger on a custom object that when a field IncludeWithOrder__c is marked as true a after update trigger is fired to add that product to the Quote as a QuoteLineItem, but I am currently getting saying that the Product2 field doesn't exist on the QuoteLineItem object, I have tried Product2Id and Product2 but neither seem to work, any help would be awesome. here is the trigger that I have currently:

 trigger WearableTrigger on Wearable__c (after update) {

    List<QuoteLineItem> item = new List<QuoteLineItem>();
        for (Wearable__c wear: Trigger.New)
            if (wear.IncludeWithOrder__c == TRUE){
                item.add(new QuoteLineItem(
                    //ProductId = wear.Product__r.Id,
                    QuoteId = wear.Quote__r.Id,
                    UnitPrice = wear.Price__c,
                    Quantity = wear.Quantity__c));
            }
        insert item;
}

Answer 1

Since you want the Id's for Product and Quote, you actually don't need to use the __r.Id versions Just replace __r.Id with __c and it will work...

Furthermore, if you want any non-ID relationship fields, those are not included in the Trigger.new context... You'll need to do as follows:

for (Wearable__c wear: [SELECT Id, Product__c, Quote__c, Price__c, Quantity__c, IncludeWithOrder__c, Product__r.SomeField__c FROM Wearable__c WHERE Id IN :Trigger.New])

Sounds like you also need the pricebookentryid, so create a map before your "for" loop:

Map<Id, Id> mapProductToPBE = new Map<Id, Id>();
for (Product2 p : [SELECT Id, Product2Id FROM PricebookEntry WHERE Pricebook2Id = :someId]) {
    mapProductToPBE.put(p.Product2Id, p.Id);
}

... then reference that in your loop by replacing //ProductId = wear.Product__r.Id with PricebookEntryId = mapProductToPBE.get(wear.Product__c)