example 'Wizerd' doesn't do the job

[Mydatafactory]

I try to rebuild the example of 'wizard'  but I get the error on line 33: Object reference not set to an instance of an object. I checked the code, but I can't find the solution.

Project.ascx.VB

	Partial Class Project
	Inherits System.Web.UI.UserControl
	Protected Sub nextButton_Click(ByVal sender As Object, ByVal e As EventArgs) Handles nextButton.Click
	UpdatePreview()
	GoToNextTab()
	End Sub
	Private Sub GoToNextTab()
	Dim tabStrip As RadTabStrip = Page.FindControl("RadTabStrip1")
	Dim FileUploadInfoTab As RadTab = tabStrip.FindTabByText("FileUpload")
	FileUploadInfoTab.Enabled = True
	FileUploadInfoTab.Selected = True
	GoToNextPageView()
	End Sub
	Private Sub GoToNextPageView()
	Dim multiPage As RadMultiPage = Page.FindControl("RadMultiPage1")
	Dim FileUploadInfoPageView As RadPageView = multiPage.FindPageViewByID("FileUpload")
	If FileUploadInfoPageView Is Nothing Then
	FileUploadInfoPageView = New RadPageView()
	FileUploadInfoPageView.ID = "FileUpload"
	multiPage.PageViews.Add(FileUploadInfoPageView)
	End If
	FileUploadInfoPageView.Selected = True
	End Sub
	Private Sub UpdatePreview()
	Dim previewControl As Control = Page.FindControl("previewControl")
	Dim ProjNameLabelPreview As Label = previewControl.FindControl("lblProjectName")
	ProjNameLabelPreview.Text = txtProjectName.Text
	Dim ProjDescriptionLabelPreview As Label = previewControl.FindControl("ProjDescriptionLabel")
	ProjDescriptionLabelPreview.Text = txtProjectDescription.Text
	Dim ReferenceLabelPreview As Label = previewControl.FindControl("ReferenceLabel")
	ReferenceLabelPreview.Text = txtReference.Text
	End Sub
	End Class

Preview.ascx

	<%@ Control Language="VB" AutoEventWireup="false" CodeFile="PreviewVB.ascx.vb" Inherits="Telerik.Web.Examples.TabStrip.ApplicationScenarios.Wizard.PreviewVB" %>
	<h2>
	Preview:</h2>
	<ul>
	<li style="text-align:left;font-weight:bold;">
	<asp:Label runat="server" ID="lblProjectName"></asp:Label>
	</li>
	<li style="text-align:left;font-weight:bold;">
	<asp:Label runat="server" ID="ProjDescriptionLabel"></asp:Label>
	</li>
	<li style="text-align:left;font-weight:bold;">
	<asp:Label runat="server" ID="ReferenceLabel"></asp:Label>
	</li>
	</ul>
	<h3>
	Files uploaded
	</h3>
	<ul>
	<asp:Label ID="lblNoResults" runat="server" Visible="true">No uploaded files</asp:Label>
	<asp:Repeater ID="rpvalidResults" runat="server" Visible="false"><HeaderTemplate>Uploaded Files:<br />
	</HeaderTemplate>
	<ItemTemplate>
	<%#DataBinder.Eval(Container.DataItem, "FileName")%>
	(<%#DataBinder.Eval(Container.DataItem, "ContentLength").ToString() + " bytes"%>) <br /><br />
	</ItemTemplate></asp:Repeater>
	</ul>

default.aspx.vb

	Partial Class Default2
	Inherits System.Web.UI.Page
	Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
	If Not Page.IsPostBack Then
	AddTab("Project", True)
	Dim pageView As New RadPageView()
	pageView.ID = "Project"
	RadMultiPage1.PageViews.Add(pageView)
	AddTab("FileUpload", False)
	AddTab("TasksToFile", False)
	End If
	End Sub
	Private Sub AddTab(ByVal tabName As String, ByVal enabled As Boolean)
	Dim tab As New RadTab(tabName)
	tab.Enabled = enabled
	RadTabStrip1.Tabs.Add(tab)
	End Sub
	Protected Sub RadMultiPage1_PageViewCreated(ByVal sender As Object, ByVal e As RadMultiPageEventArgs) Handles RadMultiPage1.PageViewCreated
	Dim pageViewContents As Control = LoadControl(e.PageView.ID & ".ascx")
	pageViewContents.ID = e.PageView.ID & "userControl"
	e.PageView.Controls.Add(pageViewContents)
	End Sub
	End Class

[Paul]

Hello A.,

The FindControl method provides you with a reference to any control. You must make sure that you properly typecast the returned value as FindControl returns a reference to a Control class. For detailed information on the subject please make a search in MSDN.

On aside note, the provided information does not help us much in reproducing the error. I'm afraid we could not be of much help unless we reproduce the issue on our side. It will be best if you can open a support ticket and send us a simple running project (incl. your custom skin, CSS, images, DB backup if needed and so on) demonstrating the problem (and step-by-step instructions on doing so). In that way we can reproduce and pinpoint the problems you're facing on our side, understand the logic of your application and provide a solution.

Regards,
Paul
the Telerik team

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