UsesItemPolicyAttribute Class
Restricts a feature provider to a specified policy.
Namespace: Microsoft.Windows.Design.Policies
Assembly: Microsoft.Windows.Design.Extensibility (in Microsoft.Windows.Design.Extensibility.dll)
Syntax
'Declaration
<AttributeUsageAttribute(AttributeTargets.Class, AllowMultiple := True)> _
Public NotInheritable Class UsesItemPolicyAttribute _
Inherits RequirementAttribute
'Usage
Dim instance As UsesItemPolicyAttribute
[AttributeUsageAttribute(AttributeTargets.Class, AllowMultiple = true)]
public sealed class UsesItemPolicyAttribute : RequirementAttribute
[AttributeUsageAttribute(AttributeTargets::Class, AllowMultiple = true)]
public ref class UsesItemPolicyAttribute sealed : public RequirementAttribute
public final class UsesItemPolicyAttribute extends RequirementAttribute
Remarks
Not all extensions support policies.
Examples
The following code example shows how to attach a custom surrogate policy to a feature provider by using UsesItemPolicyAttribute. For a full code listing, see How to: Create a Surrogate Policy.
' The DockPanelAdornerProvider class implements an adorner
' that you can use to set the Margin property by using a
' drag operation. The DockPanelPolicy class enables a
' container policy for offering additional tasks and
' adorners on the panel's children.
<UsesItemPolicy(GetType(DockPanelPolicy))> _
Class DockPanelAdornerProvider
Inherits AdornerProvider
Public Sub New()
' The adorner is a Rectangle element.
Dim r As New Rectangle()
r.Width = 23.0
r.Height = 23.0
r.Fill = AdornerColors.GlyphFillBrush
' Set the rectangle's placement in the adorner panel.
Dim placement As New AdornerPlacementCollection()
placement.PositionRelativeToAdornerWidth(-1, 0)
placement.SizeRelativeToAdornerDesiredHeight(1.0, 0)
placement.SizeRelativeToAdornerDesiredWidth(1.0, 0)
placement.PositionRelativeToAdornerHeight(-1.0, 0)
AdornerPanel.SetPlacements(r, placement)
Dim p As New AdornerPanel()
p.Children.Add(r)
AdornerPanel.SetTask(r, New DockPanelMarginTask())
Adorners.Add(p)
End Sub
End Class
// The DockPanelAdornerProvider class implements an adorner
// that you can use to set the Margin property by using a
// drag operation. The DockPanelPolicy class enables a
// container policy for offering additional tasks and
// adorners on the panel's children.
[UsesItemPolicy(typeof(DockPanelPolicy))]
class DockPanelAdornerProvider : AdornerProvider
{
public DockPanelAdornerProvider()
{
// The adorner is a Rectangle element.
Rectangle r = new Rectangle();
r.Width = 23.0;
r.Height = 23.0;
r.Fill = AdornerColors.GlyphFillBrush;
// Set the rectangle's placement in the adorner panel.
AdornerPlacementCollection placement = new AdornerPlacementCollection();
placement.PositionRelativeToAdornerWidth(-1, 0);
placement.SizeRelativeToAdornerDesiredHeight(1.0, 0);
placement.SizeRelativeToAdornerDesiredWidth(1.0, 0);
placement.PositionRelativeToAdornerHeight(-1.0, 0);
AdornerPanel.SetPlacements(r, placement);
AdornerPanel p = new AdornerPanel();
p.Children.Add(r);
AdornerPanel.SetTask(r, new DockPanelMarginTask());
Adorners.Add(p);
}
}
Inheritance Hierarchy
System.Object
System.Attribute
Microsoft.Windows.Design.RequirementAttribute
Microsoft.Windows.Design.Policies.UsesItemPolicyAttribute
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.
See Also
Reference
UsesItemPolicyAttribute Members
Microsoft.Windows.Design.Policies Namespace