' This class defines the designer actions that appear on the control
' that is being designed.
Friend Class DemoActionList
Inherits System.ComponentModel.Design.DesignerActionList
' Cache a reference to the designer host.
Private host As IDesignerHost = Nothing
' Cache a reference to the control.
Private relatedControl As DemoControl = Nothing
' Cache a reference to the designer.
Private relatedDesigner As DemoControlDesigner = Nothing
'The constructor associates the control
'with the designer action list.
Public Sub New(ByVal component As IComponent)
MyBase.New(component)
Me.relatedControl = component '
Me.host = Me.Component.Site.GetService(GetType(IDesignerHost))
Dim dcd As IDesigner = host.GetDesigner(Me.Component)
Me.relatedDesigner = dcd
End Sub
' This method creates and populates the
' DesignerActionItemCollection which is used to
' display designer action items.
Public Overrides Function GetSortedActionItems() As DesignerActionItemCollection
Dim items As New DesignerActionItemCollection()
' If the Timer component has not been created, show the
' "Create Timer" DesignerAction item.
'
' If the Timer component exists, show the timer-related
' options.
If Me.relatedDesigner.createdTimer Is Nothing Then
items.Add(New DesignerActionMethodItem(Me, "CreateTimer", "Create Timer", True))
Else
items.Add(New DesignerActionMethodItem(Me, "ShowEventHandlerCode", "Show Event Handler Code", True))
items.Add(New DesignerActionMethodItem(Me, "RemoveTimer", "Remove Timer", True))
End If
items.Add(New DesignerActionMethodItem(Me, "GetExtenderProviders", "Get Extender Providers", True))
items.Add(New DesignerActionMethodItem(Me, "GetDemoControlReferences", "Get DemoControl References", True))
items.Add(New DesignerActionMethodItem(Me, "GetPathOfAssembly", "Get Path of Executing Assembly", True))
items.Add(New DesignerActionMethodItem(Me, "GetComponentTypes", "Get ScrollableControl Types", True))
items.Add(New DesignerActionMethodItem(Me, "GetToolboxCategories", "Get Toolbox Categories", True))
items.Add(New DesignerActionMethodItem(Me, "SetBackColor", "Set Back Color", True))
Return items
End Function
' This method creates a Timer component using the
' IDesignerHost.CreateComponent method. It also
' creates an event handler for the Timer component's
' tick event.
Private Sub CreateTimer()
If (Me.host IsNot Nothing) Then
If Me.relatedDesigner.createdTimer Is Nothing Then
' Create and configure the Timer object.
Me.relatedDesigner.createdTimer = Me.host.CreateComponent(GetType(Timer))
Dim t As Timer = Me.relatedDesigner.createdTimer
t.Interval = 1000
t.Enabled = True
Dim eventColl As EventDescriptorCollection = TypeDescriptor.GetEvents(t, New Attribute(-1) {})
If (eventColl IsNot Nothing) Then
Dim ed As EventDescriptor = eventColl("Tick")
If (ed IsNot Nothing) Then
Dim epd As PropertyDescriptor = Me.relatedDesigner.eventBindingService.GetEventProperty(ed)
epd.SetValue(t, "timer_Tick")
End If
End If
Me.relatedDesigner.actionUiService.Refresh(Me.relatedControl)
End If
End If
End Sub
' This method uses the IEventBindingService.ShowCode
' method to start the Code Editor. It places the caret
' in the timer_tick method created by the CreateTimer method.
Private Sub ShowEventHandlerCode()
Dim t As Timer = Me.relatedDesigner.createdTimer
If (t IsNot Nothing) Then
Dim eventColl As EventDescriptorCollection = TypeDescriptor.GetEvents(t, New Attribute(-1) {})
If (eventColl IsNot Nothing) Then
Dim ed As EventDescriptor = eventColl("Tick")
If (ed IsNot Nothing) Then
Me.relatedDesigner.eventBindingService.ShowCode(t, ed)
End If
End If
End If
End Sub
' This method uses the IDesignerHost.DestroyComponent method
' to remove the Timer component from the design environment.
Private Sub RemoveTimer()
If (Me.host IsNot Nothing) Then
If (Me.relatedDesigner.createdTimer IsNot Nothing) Then
Me.host.DestroyComponent(Me.relatedDesigner.createdTimer)
Me.relatedDesigner.createdTimer = Nothing
Me.relatedDesigner.actionUiService.Refresh(Me.relatedControl)
End If
End If
End Sub
' This method uses IExtenderListService.GetExtenderProviders
' to enumerate all the extender providers and display them
' in a MessageBox.
Private Sub GetExtenderProviders()
If (Me.relatedDesigner.listService IsNot Nothing) Then
Dim sb As New StringBuilder()
Dim providers As IExtenderProvider() = Me.relatedDesigner.listService.GetExtenderProviders()
Dim i As Integer
For i = 0 To providers.Length - 1
Dim o As Object = providers(i)
sb.Append(o.ToString())
sb.Append(ControlChars.Cr + ControlChars.Lf)
Next i
MessageBox.Show(sb.ToString(), "Extender Providers")
End If
End Sub
' This method uses the IReferenceService.GetReferences method
' to enumerate all the instances of DemoControl on the
' design surface.
Private Sub GetDemoControlReferences()
If (Me.relatedDesigner.referenceService IsNot Nothing) Then
Dim sb As New StringBuilder()
Dim refs As Object() = Me.relatedDesigner.referenceService.GetReferences(GetType(DemoControl))
Dim i As Integer
For i = 0 To refs.Length - 1
sb.Append(refs(i).ToString())
sb.Append(ControlChars.Cr + ControlChars.Lf)
Next i
MessageBox.Show(sb.ToString(), "DemoControl References")
End If
End Sub
' This method uses the ITypeResolutionService.GetPathOfAssembly
' method to display the path of the executing assembly.
Private Sub GetPathOfAssembly()
If (Me.relatedDesigner.typeResService IsNot Nothing) Then
Dim name As System.Reflection.AssemblyName = System.Reflection.Assembly.GetExecutingAssembly().GetName()
MessageBox.Show(Me.relatedDesigner.typeResService.GetPathOfAssembly(name), "Path of executing assembly")
End If
End Sub
' This method uses the IComponentDiscoveryService.GetComponentTypes
' method to find all the types that derive from
' ScrollableControl.
Private Sub GetComponentTypes()
If (Me.relatedDesigner.componentDiscoveryService IsNot Nothing) Then
Dim components As ICollection = Me.relatedDesigner.componentDiscoveryService.GetComponentTypes(host, GetType(ScrollableControl))
If (components IsNot Nothing) Then
If components.Count > 0 Then
Dim sb As New StringBuilder()
Dim e As IEnumerator = components.GetEnumerator()
While e.MoveNext()
sb.Append(e.Current.ToString())
sb.Append(ControlChars.Cr + ControlChars.Lf)
End While
MessageBox.Show(sb.ToString(), "Controls derived from ScrollableControl")
End If
End If
End If
End Sub
' This method uses the IToolboxService.CategoryNames
' method to enumerate all the categories that appear
' in the Toolbox.
Private Sub GetToolboxCategories()
If (Me.relatedDesigner.toolboxService IsNot Nothing) Then
Dim sb As New StringBuilder()
Dim names As CategoryNameCollection = Me.relatedDesigner.toolboxService.CategoryNames
Dim name As String
For Each name In names
sb.Append(name.ToString())
sb.Append(ControlChars.Cr + ControlChars.Lf)
Next name
MessageBox.Show(sb.ToString(), "Toolbox Categories")
End If
End Sub
' This method sets the shadowed BackColor property on the
' designer. This is the value that is serialized by the
' design environment.
Private Sub SetBackColor()
Dim d As New ColorDialog()
If d.ShowDialog() = DialogResult.OK Then
Me.relatedDesigner.BackColor = d.Color
End If
End Sub
End Class
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