Why is it null?

[Bruno]

Hi guys,

I have a tree view and I use a call to Expand only the first level so the user can see the first node expended.

IE, Safari and Chrome do not see RadTreeView only FF and Opera

What am I doing wrong here?

code:

The RadTreeView

<telerik:RadTreeView ID="RadTreeView" runat="server" OnNodeDataBound="RadTreeView_NodeDataBound"
    OnClientNodeClicked="onClientNodeClickedHandler" OnClientMouseOver="onClientMouseOverHandler"
    CheckBoxes="false" CheckChildNodes="false" MultipleSelect="true" TriStateCheckBoxes="false"
    SingleExpandPath="true" BorderColor="LightGray" BorderWidth="0">
</telerik:RadTreeView>

The call

$(document).ready(function() {
   // expand until level
   treeExpandNodes(0);
});

   function treeExpandNodes(level) {
      var treeView = $find('<%= RadTreeView.ClientID %>');
      if (treeView != null) {
         var nodes = treeView.get_allNodes();

         for (var i = 0; i < nodes.length; i++) {
            if (nodes[i].get_nodes() != null) {
               if (nodes[i].get_level() <= level)
                  nodes[i].expand();
               else
                  nodes[i].collapse();
            }
         }
      }
      else
         alert('Why is it null?'); // only in FF and Opera this alert is not called!
   }

image of the output in the 4 browsers

[Bruno]

it will work if I delay the call by 100 ms


      setTimeout(function() { treeExpandNodes(0); }, 100);

the DOM is already created, should be immediately as I could see the flick of the RadTreeView showing the first node (All Collapsed) and then the expanded until the level I wanted.

[Veselin Vasilev]

Hi Bruno,

The document ready state is a little bit early in the page life cycle and the client objects are not yet initialized. That is why it works when a timeout is added.
The safest way would be to use the pageLoad or the Sys.Application.add_load() method:

function pageLoad()
{
   treeExpandNodes(0);
}

All the best,
Veselin Vasilev
the Telerik team

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