[Solved] Selecting an item in Treeview inside a Combobox

[Andrew]

I have a hierarchial TreeView inside a combo box. The basic functionality is fine except for the following scenario:
When the edit page is loaded we already know the value of a treeNode. When I click on the drop down button on the combobox,
as it is now, the treeview is displayed with all nodes closed.
I would like the tree view to expand to the proper level with the selected node highlighted. I tried doing this:
       _onClientDropDownOpening: function(sender, e)
        {            
            var selectedNode = this._ObjectiveTypeTreeView.get_selectedNode();
            if (selectedNode != null)
            {
                selectedNode.scrollIntoView();
            }
        },
but it doesn't work. I would appreciate any pointers.
Thanks!

[Veronica]

Hi Andrew,

Thanks for the question.

From your code snippet I suppose you are using the OnClientDropDownOpening event. If you take a look at this demo you may see that a similar function is used but in OnClientDropDownOpened event.

<telerik:RadComboBox ID="RadComboBox1" runat="server" Style="vertical-align: middle;"
            OnClientDropDownOpened="OnClientDropDownOpenedHandler" EmptyMessage="Choose a destination"
            ExpandAnimation-Type="None" CollapseAnimation-Type="None">

function OnClientDropDownOpenedHandler(sender, eventArgs) {
    var tree = sender.get_items().getItem(0).findControl("RadTreeView1");
    var selectedNode = tree.get_selectedNode();
    if (selectedNode) {
        selectedNode.scrollIntoView();
    }
}

I've made an example similar to the demo above.  You can find it in the attached .zip file.

Please let me know if this was helpful.

Greetings,
Veronica Milcheva
the Telerik team

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