RadTreeView State

[Vme]

Hello,

I'm trying to maintain the state of my RadTreeView in my master page as i navigate from content page to content page.  I have everything working except for the face that when I collapse my nodes and switch pages they open back up when I change content pages.  I know its because I'm using clientside for my TreeNodeExpandMode, but if I switch it to ServerSideCallBack once the post back is completed even though the nodes say Expanded="True" I get a '+' sign and it loads on demand again. I just have two hyperlinks on my page that switch from Page1.aspx and Page2.aspx.  Page1/2.aspx both use Site1.Master as their master page.   Any suggestions would be great!  Thank you.  

Here is my master page code:

public partial class Site1 : System.Web.UI.MasterPage
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack && String.IsNullOrEmpty((string)Session["treeViewState"]))
            {
                LoadRootNodes();
                Session["treeViewState"] = RadTreeView1.GetXml();
            }
            else if (!String.IsNullOrEmpty((string)Session["treeViewState"]))
            {
                this.RadTreeView1.LoadXml((string)Session["treeViewState"]);
            }
        }

        private void LoadRootNodes()
        {
            for (int i = 0; i < 5; i++)
            {
                this.RadTreeView1.Nodes.Add(new RadTreeNode()
                {
                    Text = String.Format("Root: {0}", i.ToString()),
                    Value = i.ToString(),
                    ExpandMode = TreeNodeExpandMode.ServerSideCallBack
                });
            }
        }

        private void AddChildNodes(RadTreeNode node)
        {
            for (int i = 0; i < 3; i++)
            {
                node.Nodes.Add(new RadTreeNode()
                {
                    Text = String.Format("{0}{1}",node.Level.ToString(), i.ToString()),
                    Value = String.Format("{0}{1}",node.Level.ToString(), i.ToString()),
                    ExpandMode = TreeNodeExpandMode.ServerSideCallBack
                });
            }
        }

        protected void RadTreeView1_NodeExpand(object sender, RadTreeNodeEventArgs e)
        {
            AddChildNodes(e.Node);

            string treeViewState = (string)Session["treeViewState"];
            RadTreeView cachedTreeView = new RadTreeView();
            cachedTreeView.LoadXmlString(treeViewState);
            RadTreeNode cachedNodeClicked = cachedTreeView.FindNodeByValue(e.Node.Value);

            AddChildNodes(cachedNodeClicked);
            cachedNodeClicked.ExpandMode = TreeNodeExpandMode.ClientSide;
            cachedNodeClicked.Expanded = true;

            Session["treeViewState"] = cachedTreeView.GetXml();
        }
    }

[Yana]

Hello,

I've modified your code so that it saves the state of the treeview now. Note that you should use the server-side onNodeCollapse event in order to change the xml when a node is collapsed. Please download the attached file and give it a try.

Kind regards,
Yana
the Telerik team

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[SoniTek]

Do you have a sample like the one above in load treeview from xml file?

[T. Tsonev]

Hello,

Please, refer to this example for populating the TreeView from XML:

http://demos.telerik.com/aspnet-ajax/treeview/examples/programming/xmlfile/defaultcs.aspx

I hope this helps.

All the best,
Tsvetomir Tsonev
the Telerik team

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