Prism for Silverlight: How to maintain views in a specific order inside a region

Question

I am creating sort of a \"Navigation panel\" (which is actually an ItemControl) for SL and using Regions to allow each module to add his link to the panel.

Problem i

Answer 1

Refering to Sam's answer you first have to build your comparer. The following one is also capable of views that do not have a dedicated wish to be positioned at. To attach this comparer to the region that has to be sorted you can use a way intruduced by the prism manual:

public partial class MainView : UserControl
{
    public MainView( ) 
    {
        InitializeComponent( );

        ObservableObject observableRegion = RegionManager.GetObservableRegion( ContentHost );

        observableRegion.PropertyChanged += ( sender, args ) =>
        {
            IRegion region = ( (ObservableObject)sender ).Value;
            region.SortComparison = CompareViews;
        };
    }

    private static int CompareViews( object x, object y )
    {
        IPositionView positionX = x as IPositionView;
        IPositionView positionY = y as IPositionView;
        if ( positionX != null && positionY != null )
        {
            //Position is a freely choosable integer
            return Comparer.Default.Compare( positionX.Position, positionY.Position );
        }
        else if ( positionX != null )
        {
            //x is a PositionView, so we favour it here
            return -1;
        }
        else if ( positionY != null )
        {
            //y is a PositionView, so we favour it here
            return 1;
        }
        else
        {
            //both are no PositionViews, so we use string comparison here
            return String.Compare( x.ToString( ), y.ToString( ) );
        }
    }
}