Solved

help with treeview populate on demand

Posted on 2007-03-17
1
2,906 Views
Last Modified: 2010-05-18
I have an issue where I am tryiong to populate a treeview programmaticaly and I would like to populate all of the child nodes "ondemand" using the populateondemand

however if I set a node to populateondemand = true;

I get the error

"PopulateOnDemand can't be set to true on a node that already has children."  

It seems pretty obvious to me that  dont understand the correct way to impliment this.

Could someone take a look at my code and suggest o me a way to have the child objects starting from the root level only populate when someones expands the node?

this is my code that fills the Treeview.

protected void Page_Load(object sender, EventArgs e)
    {
   

                     tvAreaTableAdapter tvAreaAdapt = new tvAreaTableAdapter();


        TreeviewDS.tvAreaDataTable areaDT = tvAreaAdapt.GetArea();
   
     
       
       
       
       foreach (DataRow r1 in areaDT)
       {
         
           long areaID = Convert.ToInt64(r1["AreaID"]);
           TreeNode anode = new TreeNode();        
           anode.Text = "Area " + r1["AreaName"].ToString();
           anode.Value = r1["AreaID"].ToString();

           anode.PopulateOnDemand = true;
     
           TreeView1.Nodes.Add(anode);
           
         
           tvRowTableAdapter tvRowAdapt = new tvRowTableAdapter();
           TreeviewDS.tvRowDataTable rowDT = tvRowAdapt.GetRows(areaID);

           foreach (DataRow r2 in rowDT)
           {
               long rowID = Convert.ToInt64(r2["RowID"]);
               TreeNode rnode = new TreeNode();
               rnode.Text = "Row " + r2["RowNumber"].ToString();
               rnode.Value = r2["RowID"].ToString();
              rnode.PopulateOnDemand = true;
             
               anode.ChildNodes.Add(rnode);

               tvVineTableAdapter tvVineAdapt = new tvVineTableAdapter();
               TreeviewDS.tvVineDataTable vineDT = tvVineAdapt.GetVines(rowID);

               foreach (DataRow r3 in vineDT)
               {
                   TreeNode vnode = new TreeNode();
                   vnode.Text = "Vine " + r3["Vine"].ToString();
                   vnode.Value = r3["VineID"].ToString();
                   rnode.ChildNodes.Add(vnode);
               }
           }

        }


    }      
0
Comment
Question by:Prysson
1 Comment
 
LVL 16

Accepted Solution

by:
AlexNek earned 500 total points
ID: 18743133
You musn't fill the full tree at the begin and you need an event handler for PopulateNode
http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.treenode.populateondemand.aspx
0

Featured Post

3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article is for Object-Oriented Programming (OOP) beginners. An Interface contains declarations of events, indexers, methods and/or properties. Any class which implements the Interface should provide the concrete implementation for each Inter…
Entity Framework is a powerful tool to help you interact with the DataBase but still doesn't help much when we have a Stored Procedure that returns more than one resultset. The solution takes some of out-of-the-box thinking; read on!
Windows 10 is mostly good. However the one thing that annoys me is how many clicks you have to do to dial a VPN connection. You have to go to settings from the start menu, (2 clicks), Network and Internet (1 click), Click VPN (another click) then fi…
Migrating to Microsoft Office 365 is becoming increasingly popular for organizations both large and small. If you have made the leap to Microsoft’s cloud platform, you know that you will need to create a corporate email signature for your Office 365…

867 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

15 Experts available now in Live!

Get 1:1 Help Now