PrimarySelectionPolicy Class

Article
02/23/2011

A policy that specifies the primarily selected element.

Inheritance Hierarchy

System.Object
  Microsoft.Windows.Design.Policies.ItemPolicy
    Microsoft.Windows.Design.Policies.SelectionPolicy
      Microsoft.Windows.Design.Policies.PrimarySelectionPolicy

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

Syntax

'Declaration
Public Class PrimarySelectionPolicy _
    Inherits SelectionPolicy

public class PrimarySelectionPolicy : SelectionPolicy

public ref class PrimarySelectionPolicy : public SelectionPolicy

type PrimarySelectionPolicy =  
    class
        inherit SelectionPolicy
    end

public class PrimarySelectionPolicy extends SelectionPolicy

The PrimarySelectionPolicy type exposes the following members.

Constructors

	Name	Description
	PrimarySelectionPolicy	Initializes a new instance of the PrimarySelectionPolicy class.

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Properties

	Name	Description
	Context	Gets the editing context for the designer. (Inherited from ItemPolicy.)
	IsSurrogate	Gets a value indicating whether the policy is a surrogate policy. (Inherited from ItemPolicy.)
	PolicyItems	Gets an enumeration of items that are affected by this policy. (Inherited from SelectionPolicy.)

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Methods

	Name	Description
	Equals	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetPolicyItems	Returns the policy item that represents the primary selection. (Overrides SelectionPolicy.GetPolicyItems(Selection).)
	GetSurrogateItems	Returns an optional set of surrogate items for this item. (Inherited from ItemPolicy.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	IsInPolicy	Gets a value indicating whether the specified item is to be included in the policy. (Inherited from SelectionPolicy.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	OnActivated	Called when this policy is activated. (Inherited from SelectionPolicy.)
	OnDeactivated	Called when this policy is deactivated. (Inherited from SelectionPolicy.)
	OnPolicyItemsChanged	Raises the PolicyItemsChanged event. (Inherited from ItemPolicy.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Events

	Name	Description
	PolicyItemsChanged	Occurs when the policy changes. (Inherited from ItemPolicy.)

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Remarks

The PrimarySelectionPolicy class is an ItemPolicy that is enabled for the primarily selected element when SelectionTool is the active tool.

Examples

The following code example shows how to implement a custom surrogate policy for the primary selection. 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;
        }
    }
}

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.