IDesignerEventService Interface
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Provides event notifications when root designers are added and removed, when a selected component changes, and when the current root designer changes.
public interface class IDesignerEventServicepublic interface IDesignerEventServicetype IDesignerEventService = interfacePublic Interface IDesignerEventServiceExamples
This example demonstrates a designer that uses the IDesignerEventService to display event notifications on a control. To use this example, compile the code to a class library. Add a reference to the library to a new Windows Forms project, and add the control within the library to the Toolbox. Add an instance of the DesignerMonitor control to a form in design mode. Right-click the control and click the Start monitoring command to display notifications of events raised by the IDesignerEventService.
#using <system.dll>
#using <system.design.dll>
#using <system.windows.forms.dll>
#using <system.drawing.dll>
using namespace System;
using namespace System::ComponentModel;
using namespace System::ComponentModel::Design;
using namespace System::Collections;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::Design;
namespace DesignerEventServiceExample
{
ref class DesignerMonitorDesigner;
// DesignerMonitor provides a display for designer event notifications.
[Designer(DesignerEventServiceExample::DesignerMonitorDesigner::typeid)]
public ref class DesignerMonitor: public UserControl
{
public:
// List to contain strings that describe designer events.
ArrayList^ updates;
bool monitoring_events;
DesignerMonitor()
{
monitoring_events = false;
updates = gcnew ArrayList;
this->BackColor = Color::White;
this->Size = System::Drawing::Size( 450, 300 );
}
protected:
// Display the message for the current mode, and any event messages if event monitoring is active.
virtual void OnPaint( PaintEventArgs^ e ) override
{
e->Graphics->DrawString( "IDesignerEventService DesignerMonitor Control", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Blue ), 5, 4 );
int yoffset = 10;
if ( !monitoring_events )
{
yoffset += 10;
e->Graphics->DrawString( "Currently not monitoring designer events.", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Black ), 5.f, yoffset + 10.f );
e->Graphics->DrawString( "Use the shortcut menu commands", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Black ), 5.f, yoffset + 30.f );
e->Graphics->DrawString( "provided by an associated DesignerMonitorDesigner", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Black ), 5.f, yoffset + 40.f );
e->Graphics->DrawString( "to start or stop monitoring.", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Black ), 5.f, yoffset + 50.f );
}
else
{
e->Graphics->DrawString( "Currently monitoring designer events.", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::DarkBlue ), 5.f, yoffset + 10.f );
e->Graphics->DrawString( "Designer created, changed and disposed events:", gcnew System::Drawing::Font( FontFamily::GenericMonospace,9 ), gcnew SolidBrush( Color::Brown ), 5.f, yoffset + 35.f );
for ( int i = 0; i < updates->Count; i++ )
{
e->Graphics->DrawString( static_cast<String^>(updates[ i ]), gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5.f, yoffset + 55.f + (10 * i) );
yoffset += 10;
}
}
}
};
// DesignerMonitorDesigner uses the IDesignerEventService to send event information
// to an associated DesignerMonitor control's updates collection.
public ref class DesignerMonitorDesigner: public ControlDesigner
{
private:
DesignerMonitor^ dm;
DesignerVerbCollection^ dvc;
int eventcount;
void StopMonitoring( Object^ /*sender*/, EventArgs^ /*e*/ )
{
IDesignerEventService^ des = dynamic_cast<IDesignerEventService^>(this->Control->Site->GetService( IDesignerEventService::typeid ));
if ( des != nullptr )
{
// Remove event handlers for event notification methods.
des->DesignerCreated -= gcnew DesignerEventHandler( this, &DesignerMonitorDesigner::DesignerCreated );
des->DesignerDisposed -= gcnew DesignerEventHandler( this, &DesignerMonitorDesigner::DesignerDisposed );
des->ActiveDesignerChanged -= gcnew ActiveDesignerEventHandler( this, &DesignerMonitorDesigner::DesignerChanged );
des->SelectionChanged -= gcnew EventHandler( this, &DesignerMonitorDesigner::SelectionChanged );
dm->monitoring_events = false;
// Rebuild menu with "Start monitoring" command.
array<DesignerVerb^>^myArray = {gcnew DesignerVerb( "Start monitoring",gcnew EventHandler( this, &DesignerMonitorDesigner::StartMonitoring ) )};
dvc = gcnew DesignerVerbCollection( myArray );
dm->Refresh();
}
}
void StartMonitoring( Object^ /*sender*/, EventArgs^ /*e*/ )
{
IDesignerEventService^ des = dynamic_cast<IDesignerEventService^>(this->Control->Site->GetService( IDesignerEventService::typeid ));
if ( des != nullptr )
{
// Add event handlers for event notification methods.
des->DesignerCreated += gcnew DesignerEventHandler( this, &DesignerMonitorDesigner::DesignerCreated );
des->DesignerDisposed += gcnew DesignerEventHandler( this, &DesignerMonitorDesigner::DesignerDisposed );
des->ActiveDesignerChanged += gcnew ActiveDesignerEventHandler( this, &DesignerMonitorDesigner::DesignerChanged );
des->SelectionChanged += gcnew EventHandler( this, &DesignerMonitorDesigner::SelectionChanged );
dm->monitoring_events = false;
// Rebuild menu with "Stop monitoring" command.
array<DesignerVerb^>^myArray = {gcnew DesignerVerb( "Stop monitoring",gcnew EventHandler( this, &DesignerMonitorDesigner::StopMonitoring ) )};
dvc = gcnew DesignerVerbCollection( myArray );
dm->Refresh();
}
}
void DesignerCreated( Object^ /*sender*/, DesignerEventArgs^ e )
{
UpdateStatus( "Designer for " + e->Designer->RootComponent->Site->Name + " was created." );
}
void DesignerDisposed( Object^ /*sender*/, DesignerEventArgs^ e )
{
UpdateStatus( "Designer for " + e->Designer->RootComponent->Site->Name + " was disposed." );
}
void DesignerChanged( Object^ /*sender*/, ActiveDesignerEventArgs^ e )
{
UpdateStatus( "Active designer moved from " + e->OldDesigner->RootComponent->Site->Name + " to " + e->NewDesigner->RootComponent->Site->Name + "." );
}
void SelectionChanged( Object^ /*sender*/, EventArgs^ /*e*/ )
{
UpdateStatus("A component selection was changed.");
}
// Update message buffer on DesignerMonitor control.
void UpdateStatus( String^ newmsg )
{
if ( dm->updates->Count > 10 )
dm->updates->RemoveAt( 10 );
dm->updates->Insert( 0, "Event #" + eventcount.ToString() + ": " + newmsg );
eventcount++;
dm->Refresh();
}
};
}
Imports System.Collections
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.Design
Namespace DesignerEventServiceExample
' DesignerMonitor provides a display for designer event notifications.
<Designer(GetType(DesignerMonitorDesigner))> _
Public Class DesignerMonitor
Inherits System.Windows.Forms.UserControl
' List to contain strings that describe designer events.
Public updates As ArrayList
Public monitoring_events As Boolean = False
Public Sub New()
updates = New ArrayList()
Me.BackColor = Color.Beige
Me.Size = New Size(450, 300)
End Sub
' Display the message for the current mode, and any event messages if monitoring events
Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
e.Graphics.DrawString("IDesignerEventService DesignerMonitor control", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Red), 5, 4)
Dim yoffset As Integer = 10
If Not monitoring_events Then
yoffset += 10
e.Graphics.DrawString("Currently not monitoring designer events.", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Black), 5, yoffset + 10)
e.Graphics.DrawString("Use the shortcut menu commands", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Black), 5, yoffset + 30)
e.Graphics.DrawString("provided by an associated DesignerMonitorDesigner", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Black), 5, yoffset + 40)
e.Graphics.DrawString("to start or stop monitoring.", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Black), 5, yoffset + 50)
Else
e.Graphics.DrawString("Currently monitoring designer events.", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.DarkBlue), 5, yoffset + 10)
e.Graphics.DrawString("Designer created, changed and disposed events:", New Font(FontFamily.GenericMonospace, 9), New SolidBrush(Color.Brown), 5, yoffset + 35)
Dim i As Integer
For i = 0 To updates.Count - 1
e.Graphics.DrawString(CStr(updates(i)), New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, yoffset + 55 + 10 * i)
yoffset += 10
Next i
End If
End Sub
End Class
' DesignerMonitorDesigner uses the IDesignerEventService to send event information
' to an associated DesignerMonitor control's updates collection.
Public Class DesignerMonitorDesigner
Inherits System.Windows.Forms.Design.ControlDesigner
Private dm As DesignerMonitor = Nothing
Private dvc As DesignerVerbCollection = Nothing
Private eventcount As Integer = 0
Public Sub New()
' Initializes the designer's shortcut menu with a "Start monitoring" command.
dvc = New DesignerVerbCollection(New DesignerVerb() {New DesignerVerb("Start monitoring", AddressOf Me.StartMonitoring)})
End Sub
Public Overrides Sub Initialize(ByVal component As System.ComponentModel.IComponent)
MyBase.Initialize(component)
Dim o As Object
o = component
If o.GetType() IsNot GetType(DesignerMonitor) Then
Throw New Exception("This designer requires a DesignerMonitor control.")
End If
dm = CType(component, DesignerMonitor)
End Sub
Public Overrides ReadOnly Property Verbs() As System.ComponentModel.Design.DesignerVerbCollection
Get
Return dvc
End Get
End Property
Private Sub StopMonitoring(ByVal sender As Object, ByVal e As EventArgs)
Dim des As IDesignerEventService = CType(Me.Control.Site.GetService(GetType(IDesignerEventService)), IDesignerEventService)
If des Is Nothing Then
Return
End If
' Remove event handlers for event notification methods.
RemoveHandler des.DesignerCreated, AddressOf Me.DesignerCreated
RemoveHandler des.DesignerDisposed, AddressOf Me.DesignerDisposed
RemoveHandler des.ActiveDesignerChanged, AddressOf Me.DesignerChanged
RemoveHandler des.SelectionChanged, AddressOf Me.SelectionChanged
dm.monitoring_events = False
' Rebuild menu with "Start monitoring" command.
dvc = New DesignerVerbCollection(New DesignerVerb() {New DesignerVerb("Start monitoring", AddressOf Me.StartMonitoring)})
dm.Refresh()
End Sub
Private Sub StartMonitoring(ByVal sender As Object, ByVal e As EventArgs)
Dim des As IDesignerEventService = CType(Me.Control.Site.GetService(GetType(IDesignerEventService)), IDesignerEventService)
If des Is Nothing Then
Return
End If
' Add event handlers for event notification methods.
AddHandler des.DesignerCreated, AddressOf Me.DesignerCreated
AddHandler des.DesignerDisposed, AddressOf Me.DesignerDisposed
AddHandler des.ActiveDesignerChanged, AddressOf Me.DesignerChanged
AddHandler des.SelectionChanged, AddressOf Me.SelectionChanged
dm.monitoring_events = True
' Rebuild menu with "Stop monitoring" command.
dvc = New DesignerVerbCollection(New DesignerVerb() {New DesignerVerb("Stop monitoring", AddressOf Me.StopMonitoring)})
dm.Refresh()
End Sub
Private Sub DesignerCreated(ByVal sender As Object, ByVal e As DesignerEventArgs)
UpdateStatus(("Designer for " + e.Designer.RootComponent.Site.Name + " was created."))
End Sub
Private Sub DesignerDisposed(ByVal sender As Object, ByVal e As DesignerEventArgs)
UpdateStatus(("Designer for " + e.Designer.RootComponent.Site.Name + " was disposed."))
End Sub
Private Sub DesignerChanged(ByVal sender As Object, ByVal e As ActiveDesignerEventArgs)
UpdateStatus(("Active designer moved from " + e.OldDesigner.RootComponent.Site.Name + " to " + e.NewDesigner.RootComponent.Site.Name + "."))
End Sub
Private Sub SelectionChanged(ByVal sender As Object, ByVal e As EventArgs)
UpdateStatus("A component selection was changed.")
End Sub
' Update message buffer on DesignerMonitor control.
Private Sub UpdateStatus(ByVal newmsg As String)
If dm.updates.Count > 10 Then
dm.updates.RemoveAt(10)
End If
dm.updates.Insert(0, "Event #" + eventcount.ToString() + ": " + newmsg)
eventcount += 1
dm.Refresh()
End Sub
End Class
End Namespace
Remarks
IDesignerEventService provides notification when a new root designer is created, changed, or disposed. A root designer provides design time support for the base component of a document in designer view. The SelectionChanged event provides notification when the current component selection has changed.
Properties
| ActiveDesigner |
Gets the root designer for the currently active document. |
| Designers |
Gets a collection of root designers for design documents that are currently active in the development environment. |
Events
| ActiveDesignerChanged |
Occurs when the current root designer changes. |
| DesignerCreated |
Occurs when a root designer is created. |
| DesignerDisposed |
Occurs when a root designer for a document is disposed. |
| SelectionChanged |
Occurs when the current design-view selection changes. |
Applies to
See also
Collaborate with us on GitHub
The source for this content can be found on GitHub, where you can also create and review issues and pull requests. For more information, see our contributor guide.
Feedback
Coming soon: Throughout 2024 we will be phasing out GitHub Issues as the feedback mechanism for content and replacing it with a new feedback system. For more information see: https://aka.ms/ContentUserFeedback.
Submit and view feedback for