Hello,
I built a custom control... Everithing is working fine...
EXCEPT... ;-) When I first place the control on the webform at design
time it showed as an empty control (it's ok), then I add my first
collection item and it also showed correctly. BUT when I close or run
the application when it came back to design time (or when I reopen the
webform) it gave me this error :
"MyCol could not be initialized"
And it doesn't render it any more (also I don't have access to any of
it properties...)
BUT at run time it's always working fine.
Any idea why (code below) ? (I searched a lot on the web and in the
news group and did not find any solution...)
Thanks a lots !!!
Robin Leblond
rleblond@jeancoutu.com
(Here is the full code, sorry there is no comment, I rewrote this code
about 5 times...)
Imports System
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.ComponentModel
Imports System.Collections
Imports System.Diagnostics
Imports System.ComponentModel.Design
Imports System.Web.UI.Design
Imports System.Drawing.Design
Imports System.IO
Imports System.Text
Namespace MyControls
<ToolboxData("<{0}:MyControl runat=server></{0}:MyControl>"), _
ParseChildren(True, "MyCol"), _
PersistChildren(False), _
ControlBuilder(GetType(MyControlBuilder)), _
Designer(GetType(MyControlDesigner))> _
Public Class MyControl
Inherits System.Web.UI.WebControls.WebControl
Implements INamingContainer
Private _MyCol As MyControlCollection
Public Sub New()
_MyCol = New MyControlCollection
End Sub
<PersistenceMode(PersistenceMode.InnerDefaultProperty), _
NotifyParentProperty(True), _
DesignerSerializationVisibility(DesignerSerializationVisibility.Visible),
_
EditorAttribute(GetType(MyControlCollectionEditor),
GetType(System.Drawing.Design.UITypeEditor))> _
Public ReadOnly Property MyCol() As MyControlCollection
Get
Return _MyCol
End Get
End Property
Public Function SupportedControls() As System.Type()
Dim TpSC() As System.Type =
{GetType(System.Web.UI.WebControls.Button)}
Return TpSC
End Function
Public Function GetDesignTimeHtml() As String
Dim FakeControlCol As New
System.Web.UI.ControlCollection(Me)
RenderControlColD(FakeControlCol)
Return GetCollectionHtml(FakeControlCol)
End Function
Private Sub RenderControlColD(ByRef FakeControlCol As
System.Web.UI.ControlCollection)
Dim i As Integer
For i = 0 To _MyCol.Count - 1
FakeControlCol.Add(_MyCol.Item(i))
Next
End Sub
Private Sub RenderControlCol()
Dim i As Integer
For i = 0 To _MyCol.Count - 1
Me.Controls.Add(_MyCol.Item(i))
Next
End Sub
Private Function GetCollectionHtml(ByRef WebControlCol As
System.Web.UI.ControlCollection) As String
Dim SW As New StringWriter
Dim HTW As New HtmlTextWriter(SW)
Dim WC As System.Web.UI.WebControls.WebControl
For Each WC In WebControlCol
WC.RenderControl(HTW)
Next
Return SW.ToString
End Function
Protected Overrides Sub Render(ByVal output As
System.Web.UI.HtmlTextWriter)
If Not Me.Site Is Nothing Then
If Me.Site.DesignMode Then
Exit Sub
End If
End If
RenderControlCol()
MyBase.Render(output)
End Sub
End Class
Public Class MyControlBuilder
Inherits ControlBuilder
Public Sub New()
MyBase.New()
End Sub
Public Function SupportedControls() As System.Type()
Dim TpSC() As System.Type =
{GetType(System.Web.UI.WebControls.Button)}
Return TpSC
End Function
Public Function GetSupportedType(ByRef SupporttedType() As
System.Type, ByVal TagName As String) As System.Type
Dim TT As System.Type
Dim TpTT As System.Type
TpTT = Nothing
For Each TT In SupporttedType
RXFramework.ErrorManagment.LogManager.LogEvent("c:\cc3.txt", TagName &
" - " & TT.Name.ToUpper)
If TagName.ToUpper.IndexOf(TT.Name.ToUpper) >= 0 Then
TT = TT
Exit For
End If
Next TT
Return TT
End Function
Public Overrides Function GetChildControlType(ByVal tagName As
String, ByVal attribs As System.Collections.IDictionary) As System.Type
Return GetSupportedType(SupportedControls(), tagName)
End Function
End Class
Public Class MyControlDesigner
Inherits ControlDesigner
Public Sub New()
MyBase.New()
End Sub
Protected Overrides Function GetEmptyDesignTimeHtml() As String
Return
CreatePlaceHolderDesignTimeHtml(GetType(Component).ToString() & "
control.")
End Function
Public Overrides ReadOnly Property AssociatedComponents() As
System.Collections.ICollection
Get
If CType(Component, MyControl).MyCol.Count > 0 Then
Return CType(Component, MyControl).MyCol
Else
Return MyBase.AssociatedComponents
End If
End Get
End Property
Public Overrides Function GetDesignTimeHtml() As String
Dim TpStr As String
If CType(Component, MyControl).MyCol.Count > 0 Then
TpStr = CType(Component, MyControl).GetDesignTimeHtml
Else
TpStr = GetEmptyDesignTimeHtml()
End If
MyBase.GetDesignTimeHtml()
Return TpStr
End Function
Protected Overrides Function GetErrorDesignTimeHtml(ByVal e As
System.Exception) As String
Return CreatePlaceHolderDesignTimeHtml("An error happen")
End Function
End Class
Public Class MyControlCollection
Inherits System.Collections.CollectionBase
Public Sub New()
list.Clear()
End Sub
Public Overrides Function ToString() As String
Return Me.GetType().Name
End Function
Public ReadOnly Property IsReadOnly() As Boolean
Get
Return False
End Get
End Property
Public Function Item(ByVal Index As Integer) As
System.Web.UI.WebControls.Button
Return list.Item(Index)
End Function
Public Sub Remove(ByVal Index As Integer)
