The ViewInjectionComposition QuickStart has a great example of what you are looking for.
What you do is delegate a command to a controller, get your scoped region out of the region manager. Once you have the scoped region, resolve a new view and add it to the region.
Here is a snippet from the quickstart that you could easily modify to do what you are looking for.
public class EmployeesController : IEmployeesController
{
private IUnityContainer container;
private IRegionManager regionManager;
public EmployeesController(IUnityContainer container, IRegionManager regionManager)
{
this.container = container;
this.regionManager = regionManager;
}
public virtual void OnEmployeeSelected(BusinessEntities.Employee employee)
{
IRegion detailsRegion = regionManager.Regions[RegionNames.DetailsRegion];
object existingView = detailsRegion.GetView(employee.EmployeeId.ToString(CultureInfo.InvariantCulture));
if (existingView == null)
{
IProjectsListPresenter projectsListPresenter = this.container.Resolve<IProjectsListPresenter>();
projectsListPresenter.SetProjects(employee.EmployeeId);
IEmployeesDetailsPresenter detailsPresenter = this.container.Resolve<IEmployeesDetailsPresenter>();
detailsPresenter.SetSelectedEmployee(employee);
IRegionManager detailsRegionManager = detailsRegion.Add(detailsPresenter.View, employee.EmployeeId.ToString(CultureInfo.InvariantCulture), true);
IRegion region = detailsRegionManager.Regions[RegionNames.TabRegion];
region.Add(projectsListPresenter.View, "CurrentProjectsView");
detailsRegion.Activate(detailsPresenter.View);
}
else
{
detailsRegion.Activate(existingView);
}
}
}