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PrimarySelectionContextMenuProvider Class

Offers a set of MenuGroup items that are shown for the current selection.

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

Syntax

'Declaration
<UsesItemPolicyAttribute(GetType(PrimarySelectionPolicy))> _
Public MustInherit Class PrimarySelectionContextMenuProvider _
    Inherits ContextMenuProvider
'Usage
Dim instance As PrimarySelectionContextMenuProvider
[UsesItemPolicyAttribute(typeof(PrimarySelectionPolicy))]
public abstract class PrimarySelectionContextMenuProvider : ContextMenuProvider
[UsesItemPolicyAttribute(typeof(PrimarySelectionPolicy))]
public ref class PrimarySelectionContextMenuProvider abstract : public ContextMenuProvider
public abstract class PrimarySelectionContextMenuProvider extends ContextMenuProvider

Remarks

Inherit from the PrimarySelectionContextMenuProvider class to add the context menu items that appear when a control is selected on the design surface. Handle the UpdateItemStatus event to set up MenuAction items before the context menu is displayed.

Examples

The following code example shows how to derive a custom type from the PrimarySelectionContextMenuProvider class. The derived type implements a custom context menu, which sets the Background property of a control at design time. For more information, see Walkthrough: Creating a MenuAction.

Imports System
Imports System.Collections.Generic
Imports System.Text
Imports Microsoft.Windows.Design.Interaction
Imports System.Windows
Imports Microsoft.Windows.Design.Model
Imports System.Windows.Controls
Imports System.Windows.Media

' The CustomContextMenuProvider class provides two context menu items 
' at design time. These are implemented with the MenuAction class. 
Class CustomContextMenuProvider
    Inherits PrimarySelectionContextMenuProvider

    Private setBackgroundToBlueMenuAction As MenuAction
    Private clearBackgroundMenuAction As MenuAction

    ' The provider's constructor sets up the MenuAction objects  
    ' and the the MenuGroup which holds them. 
    Public Sub New()

        ' Set up the MenuAction which sets the control's  
        ' background to Blue.
        setBackgroundToBlueMenuAction = New MenuAction("Blue")
        setBackgroundToBlueMenuAction.Checkable = True 
        AddHandler setBackgroundToBlueMenuAction.Execute, AddressOf SetBackgroundToBlue_Execute

        ' Set up the MenuAction which sets the control's  
        ' background to its default value.
        clearBackgroundMenuAction = New MenuAction("Cleared")
        clearBackgroundMenuAction.Checkable = True 
        AddHandler clearBackgroundMenuAction.Execute, AddressOf ClearBackground_Execute

        ' Set up the MenuGroup which holds the MenuAction items. 
        Dim backgroundFlyoutGroup As New MenuGroup("SetBackgroundsGroup", "Set Background")

        ' If HasDropDown is false, the group appears inline,  
        ' instead of as a flyout. Set to true.
        backgroundFlyoutGroup.HasDropDown = True
        backgroundFlyoutGroup.Items.Add(setBackgroundToBlueMenuAction)
        backgroundFlyoutGroup.Items.Add(clearBackgroundMenuAction)
        Me.Items.Add(backgroundFlyoutGroup)

        ' The UpdateItemStatus event is raised immediately before  
        ' this provider shows its tabs, which provides the opportunity  
        ' to set states. 
        AddHandler UpdateItemStatus, AddressOf CustomContextMenuProvider_UpdateItemStatus

    End Sub 

    ' The following method handles the UpdateItemStatus event. 
    ' It sets the MenuAction states according to the state 
    ' of the control's Background property. This method is 
    ' called before the context menu is shown. 
    Sub CustomContextMenuProvider_UpdateItemStatus( _
        ByVal sender As Object, _
        ByVal e As MenuActionEventArgs)

        ' Turn everything on, and then based on the value  
        ' of the BackgroundProperty, selectively turn some off.
        clearBackgroundMenuAction.Checked = False
        clearBackgroundMenuAction.Enabled = True
        setBackgroundToBlueMenuAction.Checked = False
        setBackgroundToBlueMenuAction.Enabled = True 

        ' Get a ModelItem which represents the selected control.  
        Dim selectedControl As ModelItem = _
            e.Selection.PrimarySelection

        ' Get the value of the Background property from the ModelItem. 
        Dim backgroundProperty As ModelProperty = _
            selectedControl.Properties(Control.BackgroundProperty)

        ' Set the MenuAction items appropriately. 
        If Not backgroundProperty.IsSet Then
            clearBackgroundMenuAction.Checked = True
            clearBackgroundMenuAction.Enabled = False 
        ElseIf backgroundProperty.ComputedValue.Equals(Brushes.Blue) Then
            setBackgroundToBlueMenuAction.Checked = True
            setBackgroundToBlueMenuAction.Enabled = False 
        End If 

    End Sub 

    ' The following method handles the Execute event.  
    ' It sets the Background property to its default value. 
    Sub ClearBackground_Execute( _
        ByVal sender As Object, _
        ByVal e As MenuActionEventArgs)

        Dim selectedControl As ModelItem = e.Selection.PrimarySelection
        selectedControl.Properties(Control.BackgroundProperty).ClearValue()

    End Sub 

    ' The following method handles the Execute event.  
    ' It sets the Background property to Brushes.Blue. 
    Sub SetBackgroundToBlue_Execute( _
        ByVal sender As Object, _
        ByVal e As MenuActionEventArgs)

        Dim selectedControl As ModelItem = e.Selection.PrimarySelection
        selectedControl.Properties(Control.BackgroundProperty).SetValue(Brushes.Blue)

    End Sub 

End Class
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Windows.Design.Interaction;
using System.Windows;
using Microsoft.Windows.Design.Model;
using System.Windows.Controls;
using System.Windows.Media;

namespace SliderAdornerLib
{
    // The CustomContextMenuProvider class provides two context menu items 
    // at design time. These are implemented with the MenuAction class. 
    class CustomContextMenuProvider : PrimarySelectionContextMenuProvider
    {
        private MenuAction setBackgroundToBlueMenuAction;
        private MenuAction clearBackgroundMenuAction;

        // The provider's constructor sets up the MenuAction objects  
        // and the the MenuGroup which holds them. 
        public CustomContextMenuProvider()
        {   
            // Set up the MenuAction which sets the control's  
            // background to Blue.
            setBackgroundToBlueMenuAction = new MenuAction("Blue");
            setBackgroundToBlueMenuAction.Checkable = true;
            setBackgroundToBlueMenuAction.Execute += 
                new EventHandler<MenuActionEventArgs>(SetBackgroundToBlue_Execute);

            // Set up the MenuAction which sets the control's  
            // background to its default value.
            clearBackgroundMenuAction = new MenuAction("Cleared");
            clearBackgroundMenuAction.Checkable = true;
            clearBackgroundMenuAction.Execute += 
                new EventHandler<MenuActionEventArgs>(ClearBackground_Execute);

            // Set up the MenuGroup which holds the MenuAction items.
            MenuGroup backgroundFlyoutGroup = 
                new MenuGroup("SetBackgroundsGroup", "Set Background");

            // If HasDropDown is false, the group appears inline,  
            // instead of as a flyout. Set to true.
            backgroundFlyoutGroup.HasDropDown = true;
            backgroundFlyoutGroup.Items.Add(setBackgroundToBlueMenuAction);
            backgroundFlyoutGroup.Items.Add(clearBackgroundMenuAction);
            this.Items.Add(backgroundFlyoutGroup);

            // The UpdateItemStatus event is raised immediately before  
            // this provider shows its tabs, which provides the opportunity  
            // to set states.
            UpdateItemStatus += 
                new EventHandler<MenuActionEventArgs>(
                    CustomContextMenuProvider_UpdateItemStatus);
        }

        // The following method handles the UpdateItemStatus event. 
        // It sets the MenuAction states according to the state 
        // of the control's Background property. This method is 
        // called before the context menu is shown. 
        void CustomContextMenuProvider_UpdateItemStatus(
            object sender, 
            MenuActionEventArgs e)
        {
            // Turn everything on, and then based on the value  
            // of the BackgroundProperty, selectively turn some off.
            clearBackgroundMenuAction.Checked = false;
            clearBackgroundMenuAction.Enabled = true;
            setBackgroundToBlueMenuAction.Checked = false;
            setBackgroundToBlueMenuAction.Enabled = true;

            // Get a ModelItem which represents the selected control. 
            ModelItem selectedControl = e.Selection.PrimarySelection;

            // Get the value of the Background property from the ModelItem.
            ModelProperty backgroundProperty = 
                selectedControl.Properties[Control.BackgroundProperty];

            // Set the MenuAction items appropriately. 
            if (!backgroundProperty.IsSet)
            {
                clearBackgroundMenuAction.Checked = true;
                clearBackgroundMenuAction.Enabled = false;
            }
            else if (backgroundProperty.ComputedValue == Brushes.Blue)
            {
                setBackgroundToBlueMenuAction.Checked = true;
                setBackgroundToBlueMenuAction.Enabled = false;
            }
        }

        // The following method handles the Execute event.  
        // It sets the Background property to its default value. 
        void ClearBackground_Execute(
            object sender, 
            MenuActionEventArgs e)
        {
            ModelItem selectedControl = e.Selection.PrimarySelection;
            selectedControl.Properties[Control.BackgroundProperty].ClearValue();
        }

        // The following method handles the Execute event.  
        // It sets the Background property to Brushes.Blue. 
        void SetBackgroundToBlue_Execute(
            object sender, 
            MenuActionEventArgs e)
        {
            ModelItem selectedControl = e.Selection.PrimarySelection;
            selectedControl.Properties[Control.BackgroundProperty].SetValue(Brushes.Blue);
        }
    }
}

Inheritance Hierarchy

System.Object
  Microsoft.Windows.Design.Features.FeatureProvider
    Microsoft.Windows.Design.Interaction.ContextMenuProvider
      Microsoft.Windows.Design.Interaction.PrimarySelectionContextMenuProvider

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

PrimarySelectionContextMenuProvider Members

Microsoft.Windows.Design.Interaction Namespace

MenuGroup

MenuAction