How to: Attach Smart Tags to a Windows Forms Component
Caution
This content was written for .NET Framework. If you're using .NET 6 or a later version, use this content with caution. The designer system has changed for Windows Forms and it's important that you review the Designer changes since .NET Framework article.
This example shows how to add smart tag support to components and custom controls.
For a complete explanation of this code example, see Walkthrough: Adding Smart Tags to a Windows Forms Component.
Example
'///////////////////////////////////////////////////////////////////
'Pull model smart tag example.
'Need references to System.dll, System.Windows.Forms.dll,
' System.Design.dll, and System.Drawing.dll.
'///////////////////////////////////////////////////////////////////
Imports System
Imports System.Drawing
Imports System.Collections
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Windows.Forms
Imports System.Text
Imports System.Reflection
Namespace SmartTags
Public Class Form1
Inherits System.Windows.Forms.Form
Private colorLabel2 As ColorLabel
Public Sub New()
InitializeComponent()
End Sub
'VS Forms Designer generated method
Private Sub InitializeComponent()
Me.colorLabel2 = New ColorLabel
Me.SuspendLayout()
'
'colorLabel2
'
Me.colorLabel2.BackColor = System.Drawing.Color.FromArgb(CType(CType(255, Byte), Integer), CType(CType(165, Byte), Integer), CType(CType(0, Byte), Integer))
Me.colorLabel2.ColorLocked = False
Me.colorLabel2.Font = New System.Drawing.Font("Arial", 12.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
Me.colorLabel2.Location = New System.Drawing.Point(41, 42)
Me.colorLabel2.Name = "colorLabel2"
Me.colorLabel2.Size = New System.Drawing.Size(117, 25)
Me.colorLabel2.TabIndex = 0
Me.colorLabel2.Text = "ColorLabel"
'
'Form1
'
Me.ClientSize = New System.Drawing.Size(292, 273)
Me.Controls.Add(Me.colorLabel2)
Me.Name = "Form1"
Me.ResumeLayout(False)
End Sub
<STAThread()> _
Shared Sub Main()
Dim f1 As New Form1()
f1.ShowDialog()
End Sub
End Class
'///////////////////////////////////////////////////////////////
'ColorLabel is a simple extension of the standard Label control,
' with color property locking added.
'///////////////////////////////////////////////////////////////
<Designer(GetType(ColorLabelDesigner))> _
Public Class ColorLabel
Inherits System.Windows.Forms.Label
Private colorLockedValue As Boolean = False
Public Property ColorLocked() As Boolean
Get
Return colorLockedValue
End Get
Set(ByVal value As Boolean)
colorLockedValue = value
End Set
End Property
Public Overrides Property BackColor() As Color
Get
Return MyBase.BackColor
End Get
Set(ByVal value As Color)
If ColorLocked Then
Return
Else
MyBase.BackColor = value
End If
End Set
End Property
Public Overrides Property ForeColor() As Color
Get
Return MyBase.ForeColor
End Get
Set(ByVal value As Color)
If ColorLocked Then
Return
Else
MyBase.ForeColor = value
End If
End Set
End Property
End Class
'///////////////////////////////////////////////////////////////
'Designer for the ColorLabel control with support for a smart
' tag panel.
'///////////////////////////////////////////////////////////////
'Must add reference to System.Design.dll
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Public Class ColorLabelDesigner
Inherits System.Windows.Forms.Design.ControlDesigner
Private lists As DesignerActionListCollection
'Use pull model to populate smart tag menu.
Public Overrides ReadOnly Property ActionLists() _
As DesignerActionListCollection
Get
If lists Is Nothing Then
lists = New DesignerActionListCollection()
lists.Add( _
New ColorLabelActionList(Me.Component))
End If
Return lists
End Get
End Property
End Class
'///////////////////////////////////////////////////////////////
'DesignerActionList-derived class defines smart tag entries and
' resultant actions.
'///////////////////////////////////////////////////////////////
Public Class ColorLabelActionList
Inherits System.ComponentModel.Design.DesignerActionList
Private colLabel As ColorLabel
Private designerActionUISvc As DesignerActionUIService = Nothing
'The constructor associates the control
'with the smart tag list.
Public Sub New(ByVal component As IComponent)
MyBase.New(component)
Me.colLabel = component
' Cache a reference to DesignerActionUIService, so the
' DesigneractionList can be refreshed.
Me.designerActionUISvc = _
CType(GetService(GetType(DesignerActionUIService)), _
DesignerActionUIService)
End Sub
'Helper method to retrieve control properties. Use of
' GetProperties enables undo and menu updates to work properly.
Private Function GetPropertyByName(ByVal propName As String) _
As PropertyDescriptor
Dim prop As PropertyDescriptor
prop = TypeDescriptor.GetProperties(colLabel)(propName)
If prop Is Nothing Then
Throw New ArgumentException( _
"Matching ColorLabel property not found!", propName)
Else
Return prop
End If
End Function
'Properties that are targets of DesignerActionPropertyItem entries.
Public Property BackColor() As Color
Get
Return colLabel.BackColor
End Get
Set(ByVal value As Color)
GetPropertyByName("BackColor").SetValue(colLabel, value)
End Set
End Property
Public Property ForeColor() As Color
Get
Return colLabel.ForeColor
End Get
Set(ByVal value As Color)
GetPropertyByName("ForeColor").SetValue(colLabel, value)
End Set
End Property
'Boolean properties are automatically displayed with binary
' UI (such as a checkbox).
Public Property LockColors() As Boolean
Get
Return colLabel.ColorLocked
End Get
Set(ByVal value As Boolean)
GetPropertyByName("ColorLocked").SetValue(colLabel, value)
' Refresh the list.
Me.designerActionUISvc.Refresh(Me.Component)
End Set
End Property
Public Property [Text]() As String
Get
Return colLabel.Text
End Get
Set(ByVal value As String)
GetPropertyByName("Text").SetValue(colLabel, value)
End Set
End Property
'Method that is target of a DesignerActionMethodItem
Public Sub InvertColors()
Dim currentBackColor As Color = colLabel.BackColor
BackColor = Color.FromArgb( _
255 - currentBackColor.R, _
255 - currentBackColor.G, _
255 - currentBackColor.B)
Dim currentForeColor As Color = colLabel.ForeColor
ForeColor = Color.FromArgb( _
255 - currentForeColor.R, _
255 - currentForeColor.G, _
255 - currentForeColor.B)
End Sub
'Implementation of this virtual method creates smart tag
' items, associates their targets, and collects into list.
Public Overrides Function GetSortedActionItems() _
As DesignerActionItemCollection
Dim items As New DesignerActionItemCollection()
'Define static section header entries.
items.Add(New DesignerActionHeaderItem("Appearance"))
items.Add(New DesignerActionHeaderItem("Information"))
'Boolean property for locking color selections.
items.Add(New DesignerActionPropertyItem( _
"LockColors", _
"Lock Colors", _
"Appearance", _
"Locks the color properties."))
If Not LockColors Then
items.Add( _
New DesignerActionPropertyItem( _
"BackColor", _
"Back Color", _
"Appearance", _
"Selects the background color."))
items.Add( _
New DesignerActionPropertyItem( _
"ForeColor", _
"Fore Color", _
"Appearance", _
"Selects the foreground color."))
'This next method item is also added to the context menu
' (as a designer verb).
items.Add( _
New DesignerActionMethodItem( _
Me, _
"InvertColors", _
"Invert Colors", _
"Appearance", _
"Inverts the fore and background colors.", _
True))
End If
items.Add( _
New DesignerActionPropertyItem( _
"Text", _
"Text String", _
"Appearance", _
"Sets the display text."))
'Create entries for static Information section.
Dim location As New StringBuilder("Location: ")
location.Append(colLabel.Location)
Dim size As New StringBuilder("Size: ")
size.Append(colLabel.Size)
items.Add( _
New DesignerActionTextItem( _
location.ToString(), _
"Information"))
items.Add( _
New DesignerActionTextItem( _
size.ToString(), _
"Information"))
Return items
End Function
End Class
End Namespace
/////////////////////////////////////////////////////////////////////
// Pull model smart tag example.
// Need references to System.dll, System.Windows.Forms.dll,
// System.Design.dll, and System.Drawing.dll.
/////////////////////////////////////////////////////////////////////
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Windows.Forms;
using System.Text;
using System.Reflection;
namespace SmartTags
{
public class Form1 : System.Windows.Forms.Form
{
private ColorLabel colorLabel2;
public Form1()
{
InitializeComponent();
}
// VS Forms Designer generated method
private void InitializeComponent()
{
this.colorLabel2 = new SmartTags.ColorLabel();
this.SuspendLayout();
//
// colorLabel2
//
this.colorLabel2.BackColor = System.Drawing.Color.Gold;
this.colorLabel2.ColorLocked = false;
this.colorLabel2.Font = new System.Drawing.Font("Arial", 12F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
this.colorLabel2.Location = new System.Drawing.Point(41, 42);
this.colorLabel2.Name = "colorLabel2";
this.colorLabel2.Size = new System.Drawing.Size(117, 25);
this.colorLabel2.TabIndex = 0;
this.colorLabel2.Text = "colorLabel2";
//
// Form1
//
this.ClientSize = new System.Drawing.Size(292, 273);
this.Controls.Add(this.colorLabel2);
this.Name = "Form1";
this.ResumeLayout(false);
}
[STAThread]
static void Main()
{
Form1 f1 = new Form1();
f1.ShowDialog();
}
}
/////////////////////////////////////////////////////////////////
// ColorLabel is a simple extension of the standard Label control,
// with color property locking added.
/////////////////////////////////////////////////////////////////
[Designer(typeof(ColorLabelDesigner))]
public class ColorLabel : System.Windows.Forms.Label
{
private bool colorLockedValue = false;
public bool ColorLocked
{
get
{
return colorLockedValue;
}
set
{
colorLockedValue = value;
}
}
public override Color BackColor
{
get
{
return base.BackColor;
}
set
{
if (ColorLocked)
return;
else
base.BackColor = value;
}
}
public override Color ForeColor
{
get
{
return base.ForeColor;
}
set
{
if (ColorLocked)
return;
else
base.ForeColor = value;
}
}
}
/////////////////////////////////////////////////////////////////
// Designer for the ColorLabel control with support for a smart
// tag panel.
// Must add reference to System.Design.dll
/////////////////////////////////////////////////////////////////
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name = "FullTrust")]
public class ColorLabelDesigner :
System.Windows.Forms.Design.ControlDesigner
{
private DesignerActionListCollection actionLists;
// Use pull model to populate smart tag menu.
public override DesignerActionListCollection ActionLists
{
get
{
if (null == actionLists)
{
actionLists = new DesignerActionListCollection();
actionLists.Add(
new ColorLabelActionList(this.Component));
}
return actionLists;
}
}
}
/////////////////////////////////////////////////////////////////
// DesignerActionList-derived class defines smart tag entries and
// resultant actions.
/////////////////////////////////////////////////////////////////
public class ColorLabelActionList :
System.ComponentModel.Design.DesignerActionList
{
private ColorLabel colLabel;
private DesignerActionUIService designerActionUISvc = null;
//The constructor associates the control
//with the smart tag list.
public ColorLabelActionList( IComponent component ) : base(component)
{
this.colLabel = component as ColorLabel;
// Cache a reference to DesignerActionUIService, so the
// DesigneractionList can be refreshed.
this.designerActionUISvc =
GetService(typeof(DesignerActionUIService))
as DesignerActionUIService;
}
// Helper method to retrieve control properties. Use of
// GetProperties enables undo and menu updates to work properly.
private PropertyDescriptor GetPropertyByName(String propName)
{
PropertyDescriptor prop;
prop = TypeDescriptor.GetProperties(colLabel)[propName];
if (null == prop)
throw new ArgumentException(
"Matching ColorLabel property not found!",
propName);
else
return prop;
}
// Properties that are targets of DesignerActionPropertyItem entries.
public Color BackColor
{
get
{
return colLabel.BackColor;
}
set
{
GetPropertyByName("BackColor").SetValue(colLabel, value);
}
}
public Color ForeColor
{
get
{
return colLabel.ForeColor;
}
set
{
GetPropertyByName("ForeColor").SetValue(colLabel, value);
}
}
// Boolean properties are automatically displayed with binary
// UI (such as a checkbox).
public bool LockColors
{
get
{
return colLabel.ColorLocked;
}
set
{
GetPropertyByName("ColorLocked").SetValue(colLabel, value);
// Refresh the list.
this.designerActionUISvc.Refresh(this.Component);
}
}
public String Text
{
get
{
return colLabel.Text;
}
set
{
GetPropertyByName("Text").SetValue(colLabel, value);
}
}
// Method that is target of a DesignerActionMethodItem
public void InvertColors()
{
Color currentBackColor = colLabel.BackColor;
BackColor = Color.FromArgb(
255 - currentBackColor.R,
255 - currentBackColor.G,
255 - currentBackColor.B);
Color currentForeColor = colLabel.ForeColor;
ForeColor = Color.FromArgb(
255 - currentForeColor.R,
255 - currentForeColor.G,
255 - currentForeColor.B);
}
// Implementation of this abstract method creates smart tag
// items, associates their targets, and collects into list.
public override DesignerActionItemCollection GetSortedActionItems()
{
DesignerActionItemCollection items = new DesignerActionItemCollection();
//Define static section header entries.
items.Add(new DesignerActionHeaderItem("Appearance"));
items.Add(new DesignerActionHeaderItem("Information"));
//Boolean property for locking color selections.
items.Add(new DesignerActionPropertyItem("LockColors",
"Lock Colors", "Appearance",
"Locks the color properties."));
if (!LockColors)
{
items.Add(new DesignerActionPropertyItem("BackColor",
"Back Color", "Appearance",
"Selects the background color."));
items.Add(new DesignerActionPropertyItem("ForeColor",
"Fore Color", "Appearance",
"Selects the foreground color."));
//This next method item is also added to the context menu
// (as a designer verb).
items.Add(new DesignerActionMethodItem(this,
"InvertColors", "Invert Colors",
"Appearance",
"Inverts the fore and background colors.",
true));
}
items.Add(new DesignerActionPropertyItem("Text",
"Text String", "Appearance",
"Sets the display text."));
//Create entries for static Information section.
StringBuilder location = new StringBuilder("Location: ");
location.Append(colLabel.Location);
StringBuilder size = new StringBuilder("Size: ");
size.Append(colLabel.Size);
items.Add(new DesignerActionTextItem(location.ToString(),
"Information"));
items.Add(new DesignerActionTextItem(size.ToString(),
"Information"));
return items;
}
}
}
Compiling the Code
Whenever you make changes to the design-time aspects of a component, you need to rebuild the control project. In addition, if there is another Windows Forms project that is currently open and uses this component, then you will probably need to refresh the project to see the changes. Typically, you need to close and reopen the design window containing the component.
Note
You must add a reference to the design-time assembly, System.Design.dll. This assembly is not included in the .NET Framework 4 Client Profile. To add a reference to System.Design.dll, you must change the project's Target Framework to .NET Framework 4.
See Also
Reference
Concepts
Designer Commands and the DesignerAction Object Model for Windows Forms