Prism, ServiceLocator and Unity container hierarchy and multi-window WPF application

Question

I want to build a WPF/Prism application where each top level window is in its own UI thread. That is fairly straight forward to do. I am using Unity as my DI container and would like to create a hierarchy of containers. In the simplest case, the root container will be at the application level and each window will have a child container. This is desirable as each window can have its own shared objects scoped by the child container.

I would like each window to have their own region manager from Prism so that I don't have any cross threading issues as each Window will have its own UI thread. I see that the Region and RegionManager use the ServiceLocator.Current singleton. This is an issue because I would like the RegionManager to use the container it is scoped to which is not possible with a static singleton. Have any of you run into this issue and how would you work around it?

Thanks!

The use the `ServiceLocator` to resolve specific objects only. If you do not need to override these on a per-window basis, I believe you can let sleeping dogs lie. Have you discovered that you *need* to override? — Jon, Apr 01 '11 at 23:31
It seems like I will need to override these in order to have a Region Navigation Service and Region Manager and Region Registry per window. I can't see a way to make this work with the current design as it uses the ServiceLocator Singleton. — m-sharp, Apr 04 '11 at 14:05
I believe that is a different issue than what the original question asks. See here: http://stackoverflow.com/questions/5276984/how-to-do-multiple-shells-in-my-prism-app-like-ms-office — Jon, Apr 04 '11 at 14:11

score 0 · Answer 1 · answered May 07 '11 at 21:41

0

You can have your Bootstrapper as child container and register your types there. And have your ServiceLocater in the application level which will call your Bootstrappers.

more info about; http://msdn.microsoft.com/en-us/library/ff649077.aspx

answered May 07 '11 at 21:41

apprich

144
7

score 0 · Answer 2 · edited Oct 27 '12 at 21:02

I actually needed to do the same thing, and I figured out the following solution:

Before navigating to the "child" region, do the following:

var childRegion = _childRegionManager.Regions["ChildRegion"];            
_childRegion.NavigationService = _childContainer.GetExportedValue<IRegionNavigationService>();
_childRegion.NavigationService.Region = _childRegion;

This sets the correct navigation service on the child region.

Of course, childContainer should have an IRegionNavigationService in its own catalog, so that it will compose it properly.

Prism, ServiceLocator and Unity container hierarchy and multi-window WPF application

2 Answers2