Setting an active tab in ASP.NET Ajax TabContainer causes the entire container to disappear

Question

I have an ASP.NET page that uses the ASP.NET Ajax Control Toolkit TabContainer . In the Page_Load event, I hide some tabs based on the data presented on the page. Then I want to activate one of the tabs based on the value of the (optional) string query parameter.

So, I have a:

 protected void Page_Load ( object sender, EventArgs e ) { if ( !this.IsPostBack ) { // Tabs with no data are hidden in here LoadDataIntoTabs(); PreselectCorrectTab(); } } private void PreselectCorrectTab () { if ( ctlTabContainer.Visible ) { if ( !string.IsNullOrEmpty( Request.QueryString[ "tabIndex" ] ) ) { int tabIndex = 0; if ( int.TryParse( Request.QueryString[ "tabIndex" ], out tabIndex ) ) { if ( ( ctlTabContainer.Tabs.Count > tabIndex ) && ctlTabContainer.Tabs[ tabIndex ].Visible ) { ctlTabContainer.ActiveTabIndex = tabIndex; } } } } } 

If I hit a page with the tabIndex query string parameter, the entire tab container will disappear.

It is strange that if I changed LoadDataIntoTabs() to non- hidden tabs that do not contain data, everything will work as you would expect (i.e. the correct tab will be selected when the page is displayed).

Any ideas?

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EDIT

In accordance with the request for more information:

 private void LoadDataIntoTabs () { LoadPendingWidgetsTab(); LoadDataIntoTab2(); LoadDataIntoTab3(); // etc... } private void LoadPendingWidgetsTab () { IList<Widget> pendingWidgets = GetAllPendingWidgets(); if ( ( pendingWidgets != null ) && ( pendingWidgets.Count > 0 ) ) { tbpPendingWidgets.Visible = true; tbpPendingWidgets.HeaderText = String.Format( "Pending Widgets ({0})", pendingWidgets.Count ); grdPendingWidgets.DataSource = pendingWidgets; grdPendingWidgets.DataBind(); } else { tbpPendingWidgets.Visible = false; } } 

Answer 1

Try setting the desired tab using ActiveTab, for example:

ctlTabContainer.ActiveTab = tbpPendingWidgets;

If you set the first tab to Visible=false , you need to set the next visible tab through ActiveTab.

I am using AjaxControlToolkit Release 30930 (September 2009).

Answer 2

This worked for me:
Manual reset of index, visibility and active tab.

  tabcontainer.ActiveTab = tabname tabcontainer.Visible = True tabcontainer.ActiveTabIndex = 2 

In another situation, when I did not try to set the active tab, I had to reset tabcontainer.ActiveTabIndex = 0 .

So I put them together, and it worked.

Answer 3

it's simple and works great, try this

assign a tab index for each tab that is used in your tab container, for example ....

then <cc1:TabContainer ID="TabContainer1" runat="server">

<cc1:TabPanel ID="tab1" runat="server" TabIndex="0"> // your panel </cc1:TabPanel> <cc1:TabPanel ID="tab2" runat="server" TabIndex="1"> // your panel </cc1:TabPanel>

</cc1:TabContainer>

write this code on the cs page

TabContainer1.ActiveTabIndex = 1;