final class MyController(TView) : Controller!TView
{
    private:
    view_defaultview defaultview;

    view_someotherview someotherview;

    public:
    this(TView view)
    {
        super(view);
    }

    @HttpMandatory Status mandatoryAction()
    {
        if (condition)
        {
            someotherview = view.getRaw!"someotherview";
            view = someotherview; // If you remove this, then it will already work, but "view" will always referre to defaultview
        }

        return Status.success;
    }

    @HttpDefault Status defaultAction()
    {
        // Don't use "view" directly. Use whichever view you need instead, unless it's generic functionality.
	if (someotherview)
        {
            ...
        }
        else
        {
            // use defaultview
        }
    }
}