ItemPolicy.IsSurrogate Property

Gets a value indicating whether the policy is a surrogate policy.

Namespace:  Microsoft.Windows.Design.Policies
Assembly:  Microsoft.Windows.Design.Interaction (in Microsoft.Windows.Design.Interaction.dll)

Syntax

'Declaration
Public Overridable ReadOnly Property IsSurrogate As Boolean
    Get
public virtual bool IsSurrogate { get; }
public:
virtual property bool IsSurrogate {
    bool get ();
}
abstract IsSurrogate : bool
override IsSurrogate : bool
function get IsSurrogate () : boolean

Property Value

Type: System.Boolean
true if the policy is a surrogate policy; otherwise, false.

Remarks

Surrogate policies offer an alternative set of items that are used to locate feature providers. Surrogate policies are most often used by control containers that offer additional tasks and adorners on their children. In this scenario, the container offers a surrogate policy in which the GetSurrogateItems method returns the parent of the item provided.

Examples

The following code example shows how to create a custom surrogate policy by implementing the IsSurrogate property and the GetSurrogateItems method. For a full code listing, see How to: Create a Surrogate Policy.

' The DockPanelPolicy class implements a surrogate policy that
' provides container semantics for a selected item. By using 
' this policy, the DemoDockPanel container control offers 
' additional tasks and adorners on its children. 
Class DockPanelPolicy
    Inherits PrimarySelectionPolicy

    Public Overrides ReadOnly Property IsSurrogate() As Boolean 
        Get
            Return True
        End Get
    End Property

    Public Overrides Function GetSurrogateItems( _
        ByVal item As Microsoft.Windows.Design.Model.ModelItem) _
        As System.Collections.Generic.IEnumerable( _
        Of Microsoft.Windows.Design.Model.ModelItem)

        Dim parent As ModelItem = item.Parent

        Dim e As New System.Collections.Generic.List(Of ModelItem)

        If (parent IsNot Nothing) Then

            e.Add(parent)

        End If

        Return e

    End Function

End Class
// The DockPanelPolicy class implements a surrogate policy that
// provides container semantics for a selected item. By using 
// this policy, the DemoDockPanel container control offers 
// additional tasks and adorners on its children. 
class DockPanelPolicy : PrimarySelectionPolicy 
{
    public override bool IsSurrogate 
    {
        get 
        { 
            return true;
        }
    }

    public override IEnumerable<ModelItem> GetSurrogateItems(ModelItem item) 
    {
        ModelItem parent = item.Parent;

        if (parent != null)
        {
            yield return parent;
        }
    }
}

.NET Framework Security

See Also

Reference

ItemPolicy Class

Microsoft.Windows.Design.Policies Namespace

PrimarySelectionPolicy

SelectionPolicy

FeatureProvider

FeatureConnectorAttribute

Other Resources

Feature Providers and Feature Connectors

Understanding WPF Designer Extensibility