Sub-classing Relation Lists (Components)

[Jeremy Shipman]

Can you give your opinion on my approach to changing the type of list
automatically produced for a has_many relation?

My example is: $order->Items() , produces a OrderItemList, instead of a
HasManyList

see:
https://gist.github.com/jedateach/5431637

Getting a result set in a custom implementation of HasManyList, means I
can change, and add extra functionality for display, and calcuation. For
example, I've overridden the sum function to include summing fields on
joined objects.

However, the way I have implemented this subclassing seems untidy/hacky.
Is there, or should there be a nicer way of sub-classing relation lists
that are automatically created?

[Nicolaas Thiemen Francken - Sunny Side Up]

It looks great.

What lines do you think needs the most tidying up / cleaning? If I look at these lines:

        $components = parent::getComponents($componentName, $filter = "", $sort = "", $join = "", $limit = null);
        if($componentName === "Items" && get_class($components) !== "UnsavedRelationList"){
            $query = $components->dataQuery();
            $components = new OrderItemList("OrderItem", "OrderID");
            if($this->model) $components->setDataModel($this->model);
            $components->setDataQuery($query);
            $components = $components->forForeignID($this->ID);
        }

Then i sort of understand what is going on - but I am not sure what you could change without a detailed knowledge of these core functions.

It appears to me that the core code perhaps could be made more "generic" so that you could achieve the above in less / clear lines?

Nicolaas

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[Jeremy Shipman]

> It appears to me that the core code perhaps could be made more
> "generic" so that you could achieve the above in less / clear lines?

My thoughts exactly.

It would be nice if I could just say (in code), "use OrderItemList
instead of HasManyList"