For result-filtered combobox functionality, I highly recommend you to look into the UXSearchBox control. You can bind the QueryText to the property in your ViewModel, perform the searching in server-side, and finally returns the data to be populated in the list.

For more information and walkthroughs on UXSearchBox, see UXSearchBox Overview.

Hope this helps,
Jimmy

Thanks Jimmy.  Just to clarify, i need auto-complete to work on a data entry form.  if a user opens the form in edit mode, i need to initialize the combobox to the currently selected value.  will the UXSearchBox support this?  I didn't see any examples under the control walkthroughs that showed this scenario.

Currently, the UXSearchBox cannot have an initial value because the ItemsSource is not yet populated.

This would require a specific data-aware ComboBox control that takes advantage of server-side capability, while still able to assign the initial value and text (with conformance to MVVM pattern as well). I've created a control request for this specific needs to be added to our roadmap this year.

- Jimmy

Thank you for submitting the control request.  I really appreciate it!

One last question -

How are your enterprise customers handling lists of 5,000+ records today?  If a data entry form displays a combobox of employee names.... are all 5,000 records downloaded everytime a new form is opened?  Or do they implement some sort of local caching scheme where lists are initialized at application startup and periodically refreshed.  Any help here would be much appreciated!

Thanks!

We're partnering with DevForce for the data access service which you can learn more here.

In such case, the master table (mostly infrequently-changed records for lookup) will be retrieved on the application startup and stored in the entity. DevForce automatically store a local copy of the cache. This allows you to bind the data in any number of forms without data reload.

You can find many of our examples that use DevForce in our latest UXGridView MVVM sample, check it out here.

Hope this helps,
Jimmy

Thank you!  I've been checking out DevForce and their stuff looks great.