Provides support for root-level designer view technologies.

For a list of all members of this type, see IRootDesigner Members.

[Visual Basic]
<ComVisible(True)>
Public Interface IRootDesigner
   Inherits IDesigner, IDisposable
[C#]
[ComVisible(true)]
public interface IRootDesigner : IDesigner, IDisposable
[C++]
[ComVisible(true)]
public __gc __interface IRootDesigner : public IDesigner,
   IDisposable
[JScript]
public
   ComVisible(true)
interface IRootDesigner implements IDesigner, IDisposable

Classes that Implement IRootDesigner

Remarks

A root designer is the designer that is in the top position, or root, of the current design-time document object hierarchy. A root designer must implement the IRootDesigner interface. A root designer typically manages the background view in designer view mode, and usually displays the controls within the base container of the current design time project.

Example

[Visual Basic, C#] The following example demonstrates a IRootDesigner implementation associated with a sample user control. This IRootDesigner implementation displays a control for the background view in designer view by overriding the GetView method. To use this example, add the source code to a project and show the RootViewSampleComponent in designer view to display the custom root designer view.

[Visual Basic] 
Imports System
Imports System.Collections
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Diagnostics
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.Design

Namespace SampleRootDesigner

    ' This sample demonstrates how to provide the root designer view, or
    ' design mode background view, by overriding IRootDesigner.GetView().

    ' This sample component inherits from RootDesignedComponent which 
    ' uses the SampleRootDesigner.
    Public Class RootViewSampleComponent
        Inherits RootDesignedComponent

        Public Sub New()
        End Sub

    End Class

    ' The following attribute associates the SampleRootDesigner designer 
    ' with the SampleComponent component.
    <Designer(GetType(SampleRootDesigner), GetType(IRootDesigner))> _
    Public Class RootDesignedComponent
        Inherits Component

        Public Sub New()
        End Sub 

    End Class 

    Public Class SampleRootDesigner
        Inherits ComponentDesigner
        Implements IRootDesigner

        ' Member field of custom type RootDesignerView, a control that 
        ' will be shown in the Forms designer view. This member is 
        ' cached to reduce processing needed to recreate the 
        ' view control on each call to GetView().
        Private m_view As RootDesignerView

        ' This method returns an instance of the view for this root
        ' designer. The "view" is the user interface that is presented
        ' in a document window for the user to manipulate. 
        Function GetView(ByVal technology As ViewTechnology) As Object Implements IRootDesigner.GetView
            If Not technology = ViewTechnology.WindowsForms Then
                Throw New ArgumentException("Not a supported view technology", "technology")
            End If
            If m_view Is Nothing Then
                ' Some type of displayable Form or control is required for a root designer that overrides 
                ' GetView(). In this example, a Control of type RootDesignerView is used.
                ' Any class that inherits from Control will work. 
                m_view = New RootDesignerView(Me)
            End If
            Return m_view
        End Function 

        ' IRootDesigner.SupportedTechnologies is a required override for an 
        ' IRootDesigner. WindowsForms is the view technology used by this designer.
        ReadOnly Property SupportedTechnologies() As ViewTechnology() Implements IRootDesigner.SupportedTechnologies
            Get
                Return New ViewTechnology() {ViewTechnology.WindowsForms}
            End Get
        End Property

        ' RootDesignerView is a simple control that will be displayed 
        ' in the designer window.
        Private Class RootDesignerView
            Inherits Control
            Private m_designer As SampleRootDesigner

            Public Sub New(ByVal designer As SampleRootDesigner)
                m_designer = designer
                BackColor = Color.Blue
                Font = New Font(Font.FontFamily.Name, 24.0F)
            End Sub 

            Protected Overrides Sub OnPaint(ByVal pe As PaintEventArgs)
                MyBase.OnPaint(pe)
                ' Draws the name of the component in large letters.
                Dim rf As New RectangleF(ClientRectangle.X, ClientRectangle.Y, ClientRectangle.Width, ClientRectangle.Height)
                pe.Graphics.DrawString(m_designer.Component.Site.Name, Font, Brushes.Yellow, rf)
            End Sub 

        End Class
    End Class

End Namespace 

[C#] 
using System;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Diagnostics;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.Design;

namespace SampleRootDesigner
{    
    // This sample demonstrates how to provide the root designer view, or
    // design mode background view, by overriding IRootDesigner.GetView().

    // This sample component inherits from RootDesignedComponent which 
    // uses the SampleRootDesigner.
    public class RootViewSampleComponent : RootDesignedComponent
    {
        public RootViewSampleComponent()
        {
        }
    }

    // The following attribute associates the SampleRootDesigner designer 
    // with the SampleComponent component.
    [Designer(typeof(SampleRootDesigner), typeof(IRootDesigner))]
    public class RootDesignedComponent : Component
    {
        public RootDesignedComponent()
        {
        }
    }

    public class SampleRootDesigner : ComponentDesigner, IRootDesigner
    {
        // Member field of custom type RootDesignerView, a control that 
        // will be shown in the Forms designer view. This member is 
        // cached to reduce processing needed to recreate the 
        // view control on each call to GetView().
        private RootDesignerView m_view;            

        // This method returns an instance of the view for this root
        // designer. The "view" is the user interface that is presented
        // in a document window for the user to manipulate. 
        object IRootDesigner.GetView(ViewTechnology technology) 
        {
            if (technology != ViewTechnology.WindowsForms)
            {
                throw new ArgumentException("Not a supported view technology", "technology");
            }
            if (m_view == null)
            {
                   // Some type of displayable Form or control is required 
                   // for a root designer that overrides GetView(). In this 
                   // example, a Control of type RootDesignerView is used.
                   // Any class that inherits from Control will work.
                m_view = new RootDesignerView(this);
            }
            return m_view;
        }

        // IRootDesigner.SupportedTechnologies is a required override for an
        // IRootDesigner. WindowsForms is the view technology used by this designer.  
        ViewTechnology[] IRootDesigner.SupportedTechnologies 
        {
            get
            {
                return new ViewTechnology[] {ViewTechnology.WindowsForms};
            }
        }

        // RootDesignerView is a simple control that will be displayed 
        // in the designer window.
        private class RootDesignerView : Control 
        {
            private SampleRootDesigner m_designer;

            public RootDesignerView(SampleRootDesigner designer)
            {
                m_designer = designer;
                BackColor = Color.Blue;
                Font = new Font(Font.FontFamily.Name, 24.0f);
            }

            protected override void OnPaint(PaintEventArgs pe)
            {
                base.OnPaint(pe);

                // Draws the name of the component in large letters.
                pe.Graphics.DrawString(m_designer.Component.Site.Name, Font, Brushes.Yellow, ClientRectangle);
            }
        }        
    }
}

[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button in the upper-left corner of the page.

Requirements

Namespace: System.ComponentModel.Design

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

Assembly: System (in System.dll)

See Also

IRootDesigner Members | System.ComponentModel.Design Namespace