Question

I notice that many of the WPF MVVM frameworks seem to avoid using the NavigationWindow and Page controls in favor of composing pages using nested UserControls.

The NavigationWindow and Page provide easy ways to enable back and forward navigation in the journal as well as providing an easy way to pass data among pages. Most MVVM frameworks I’ve seen re-implement these features in various ways.

Is there a specific reason to avoid using NavigationWindow and Page?

Answer 1

“NavigationWindow does not store an
instance of a content object in
navigation history. Instead,
NavigationWindow creates a new
instance of the content object each
time it is navigated to by using
navigation history. This behavior is
designed to avoid excessive memory
consumption when large numbers and
large pieces of content are being
navigated to. Consequently, the state
of the content is not remembered from
one navigation to the next. However,
WPF provides several techniques by
which you can store a piece of state
for a piece of content in navigation
history….”

http://msdn.microsoft.com/en-us/library/system.windows.navigation.navigationwindow.aspx