Prism / MEF new view not getting a new viewmodel from MEF import
I have a tabbed application where I want the user to be able to search for a person and then, in a new view, show the person's details. The user should be able to have multiple person detail views open for different people.
I was a little unsure if I am following the correct procedure for creating my new view. Using Unity (which I am not) it seems you would call Container.Resolve(view)
however I am doing the following, the satisfyImports was necessary in order for my imports in the view / viewmodel to be created.
PersonDetailView view = new PersonDetailView();
_container.Satisfy开发者_开发技巧ImportsOnce(view);
_regionManager.Regions["MainRegion"].Add(view, this.SelectedPerson.Name);
_regionManager.RequestNavigate("MainRegion", new Uri("PersonDetailView", UriKind.Relative));
In the code for my PersonDetailView I have the following property to set the data context.
[Import]
public PersonDetailsViewModel ViewModel
{
set
{
this.DataContext = value;
}
}
This seems to work but the trouble I am having is that when I create a second person view, the new view is getting the same instance of the datacontext as the view that is already created.
Is this because I am creating my views incorrectly or is there a way that I tell MEF to create a new oject when it fulfills the imports for my new view?
When you export a part, by default it used a CreationPolicy
of Shared
. This essentially makes the exported instance a singleton in the container. With your export, add another attribute:
[Export, PartCreationPolicy(CreationPolicy.NonShared)]
public class Foo { }
This will ensure a new instance is created each time you call to compose the consumer instance.
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