A collection of useful form types and extensions for Symfony2.
Note: Documenting these form types is an ongoing effort. We'd appreciate any feedback, corrections additions you can provide.
Installation instructions can be found here
The PolyCollection form type allows you to create a collection type on a property where the relationship is to a polymorphic object structure like Doctrine2's Single or Multi table inheritance.
For example, if you had an Invoice entity that had a relationship to an
entity that was using Doctrine inheritance InvoiceLine and you wanted
to define multiple InvoiceLine types depending on what you wanted to invoice
like InvoiceProductLine, InvoiceShippingLine and InvoiceDiscountLine
you could use this form type to achieve a form collection that would support
all 4 types of InvoiceLine inside the same collection.
For more information see PolyCollection Documentation
The CheckboxGrid form type allows editing many-to-many relationships with a grid of checkboxes. It has handy shortcuts for Doctrine entities but can also be used with arrays of regular objects.
For example, a company might sell multiple products, and operate in different areas. Any of its salesmen could sell any combination of products in areas. The salesman form needs a table of checkboxes where the rows are products and the columns are areas (or vice versa!)
For more information see CheckboxGrid Documentation