Classe PrimarySelectionPolicy

Artigo
08/25/2010

Uma diretiva que especifica o elemento principalmente selecionado.

Namespace: Microsoft.Windows.Design.Policies
Assembly: Microsoft.Windows.Design.Extensibility (em Microsoft.Windows.Design.Extensibility.dll)

Sintaxe

Public Class PrimarySelectionPolicy _
    Inherits SelectionPolicy

Dim instance As PrimarySelectionPolicy

public class PrimarySelectionPolicy : SelectionPolicy

public ref class PrimarySelectionPolicy : public SelectionPolicy

public class PrimarySelectionPolicy extends SelectionPolicy

Comentários

The PrimarySelectionPolicy classe é um ItemPolicy que está habilitada para o elemento selecionado principalmente quando SelectionTool é a ferramenta ativo.

Exemplos

O exemplo de código a seguir mostra como implementar uma diretiva do substituto personalizado para a seleção principal.Para obter uma listagem de código completo, consulte Como: Criar uma diretiva substituto.

' 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;
        }
    }
}

Hierarquia de herança

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

Acesso thread-safe

Quaisquer membros static (Shared no Visual Basic) públicos deste tipo são thread-safe. Não há garantia de que qualquer membro de instância seja thread-safe.