Transferring just one View Template from Project to Project

Luke asks:

Let’s say you have 100 view templates in a project, and you make a new one.  You want to transfer only that new template to another project (not the other 100 View Templates).  If you use Transfer Project Standards (on View Templates and Filters), you will get the lot.  How can we transfer just one of them?

This is a great opportunity to show Revit 2014’s new ability to copy elements from one document to another.

public void CopyTemplate()
{
    Document doc = this.ActiveUIDocument.Document;

    // get the id of the view template assigned to the active view
    ElementId templateId = doc.ActiveView.ViewTemplateId;
    if (templateId == ElementId.InvalidElementId)
    {
        TaskDialog.Show("Error", "Active view must have a view template assigned.");
        return;
    }

    // find the other open document in this session of Revit
    Application app = this.Application;
    Document otherDoc = app.Documents.Cast<Document>().Where(d => d.Title != doc.Title).FirstOrDefault();
    if (otherDoc == null)
    {
        TaskDialog.Show("Error", "There must be a 2nd document open.");
        return;
    }

    // add the template id to a collection
    // must have 'using System.Collections.ObjectModel;' to use 'new Collection'
    ICollection<ElementId> copyIds = new Collection<ElementId>();
    copyIds.Add(templateId);

    // create a default CopyPasteOptions
    CopyPasteOptions cpOpts = new CopyPasteOptions();

    // create a new transaction in the other document
    using (Transaction t = new Transaction(otherDoc, "Copy View Template"))
    {
        t.Start();
        // perform the copy into the other document using this new 2014 feature
        ElementTransformUtils.CopyElements(doc, copyIds, otherDoc, Transform.Identity, cpOpts);
        t.Commit();
    }
}