Ajax Tookit TabPanel Invisible Tag Bug

Question

I have encountered a slightly bizarre bug while using the ajax control toolkit TabPanel. I have 4 tabs in row like so:

[Tab1][Tab2][Tab3][Tab4]

Now tab 2 sho

Answer 1

I'm not sure if this is the same issue but it sounds similar to one that i've had for few months. Have a look here for my problem and the solution:

• forums.asp.net: hiding TabContainer TabPanels

I had to fix a Bug in Ajax-Toolkit from PreRender:

Private Sub Page_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreRender
    'ensure that the Tabs stay invisible that have Visible=False on markup and dont get visible programmatically'  
    Me.TabThatShouldStayInvisible.Visible = False
    FixTabPanelVisible(TabContainer1)
End Sub

Protected Sub FixTabPanelVisible(ByVal tabcontainer As AjaxControlToolkit.TabContainer)
    For Each tp As AjaxControlToolkit.TabPanel In tabcontainer.Tabs
        Dim oldVisible As Boolean = CBool(IIf(IsNothing(ViewState(tp.UniqueID + "_Display")), True, ViewState(tp.UniqueID + "_Display")))
        If Not tp.Visible Then
            ViewState(tp.UniqueID + "_Display") = False
            DisableTab(tabcontainer, tabcontainer.Tabs.IndexOf(tp))
        ElseIf tp.Visible AndAlso Not oldVisible Then
            ViewState(tp.UniqueID + "_Display") = True
            EnableTab(tabcontainer, tabcontainer.Tabs.IndexOf(tp))
        End If
        tp.Visible = True
    Next
    Dim fixScript As New StringBuilder()
    fixScript.Append("function DisableTab(container, index) {$get(container.get_tabs()[index].get_id() + ""_tab"").style.display = ""none"";}")
    fixScript.Append("function EnableTab(container, index) {$get(container.get_tabs()[index].get_id() + ""_tab"").style.display = """";}")
    ScriptManager.RegisterStartupScript(Me, Me.GetType(), "FixScriptReg", fixScript.ToString(), True)
End Sub

Protected Sub EnableTab(ByVal container As AjaxControlToolkit.TabContainer, ByVal index As Integer)
    Dim sFunction As String = "function () {EnableTab($find('" & container.ClientID & "')," & index & ");}"
    ScriptManager.RegisterStartupScript(Me, Me.GetType(), "EnableTabFun" & index, "Sys.Application.add_load(" & sFunction & ");", True)
End Sub

Protected Sub DisableTab(ByVal container As AjaxControlToolkit.TabContainer, ByVal index As Integer)
    Dim sFunction As String = "function () {DisableTab($find('" & container.ClientID & "')," & index & ");}"
    ScriptManager.RegisterStartupScript(Me, Me.GetType(), "DisableTabFun" & index, "Sys.Application.add_load(" & sFunction & ");", True)
End Sub