Setting DataContext in UserControl from ViewModel

Question

I have a View that contains a Listbox. I'll call it CityListingPage.xaml. This list page has a CityListingViewModel, that is binded with the View like somewhat like this:

DataContext="{Binding CityListing, Source={StaticResource Locator}}"

This works nicely. Now I what to change my page to a Pivot Control, where the Pivot Items, would be instances of CityListingViewModel, but obviously with different constructor data (ie. Country)

I extracted the ListBox into a UserControl. Now I'm struggling how to make this work so that for each list I get a new instance of the CityListingViewModel.

I tried creating in the ViewModelLocator a collection of CityListingViewModels but how do I pass the a CityListingViewModel instance to the UserControls DataContext?

Perhaps there is a different, better way of doing this?

Answer 1

Without seeing your code, I'm going to do a little guessing, but I think you can do it directly via data binding. Since each pivot item is getting an instance of CityListingViewModel, you can just pass that binding along to the UserControl:

If you post a little more code showing what you're trying to do, we might be able to be of more help.

Answer 2

The following are two answers for using a collection to create panorama pages. But I am quite sure that the approach can be adapted to pivot pages:

• Dynamically add eventtocommand actions to a listbox
• Static and dynamic panorama items in a panorama wp7 mvvm

The second post should be more relevant.

Answer 3

If you are thinking of partitioning the same data over multiple views on a pivot page then I would suggest NOT using several view models, especially if it is the same datasource you are using for all the data.

Simply have a parameter which each view would bind to and use Linq to control what data is visible to that parameter.

So you will have the variable which will contain all the data to be displayed and one parameter per view querying that data.