type=page factorys

The contents of a factorys of type=page specify the x::w::pagefactory methods that get invoked when generating the contents of a page container:

halign and valign

These elements invoke the corresponding x::w::pagefactory methods:

<factory type="page" id="maincontents">
  <halign>center</halign>
  <valign>middle</valign>

  <!-- ... -->

</factory>

These elements contain x::w::halign values and x::w::valign values.

Inherited generic factory methods

<factory type="page" id="pages">

  <halign>center</halign>
  <valign>middle</valign>

  <container>
    <type>grid</type>
    <name>initial-options</name>
  </container>
</factory>

<layout type="grid" id="initial-options">

  <!-- ... -->

</layout>

A page factory element contains any element that's valid in a generic factory. This creates a new page. The new element is usually a container.