Designer manages the relationship between the XForms data model and the items on the form.
When you create a new form, Designer automatically generates a model with an empty data instance. As you build the form, Designer keeps the generated instance synchronized with the form. When you add items to the form, Designer adds elements to the generated instance, and when you delete items, Designer removes the corresponding element from the generated instance.
The structure of the generated instance reflects the structure of your form. However, this structure might not conform to the requirements of your backend processing systems. Therefore, at any stage during the design and construction of your form, you can create one or more additional instances which you then customize to meet your needs. You can create instances manually, or you can create them from an existing schema or an existing WSDL message.
After you create a new instance, you can use Designer to bind existing form items to the elements of the new instance. Designer will automatically adjust the generated instance to reflect the changes.
Parent topic: Developing forms