Hello Prajakta, 

Thank you for posting in the community.
It seems your code attachment is missing.

Please notice the product version you are using is no longer shipped and supported as it is considered retired.

Reference to the product LifeCycle page: https://www.infragistics.com/support/product-lifecycle

I strongly suggest you to upgrade to more modern product version and take advantage of the up-to-date architecture and support in modern browsers.

Here is an online sample illustrating the use of Ajax Indicator for our Aikido Controls https://www.infragistics.com/samples/aspnet/data-tree/ajax-indicator

Regarding your particular asking here is an example of implementation of such loading indication "How to a Progress Indicator During DemandLoad Of The UltraWebTree":

Declare InitializeTree and DemandLoad event handlers in the ClientSideEvents of the UltraWebTree.

<ClientSideEvents InitializeTree="func_initializeTree" DemandLoad="func_demandLoad" />

The DemandLoad event handler will respond when the user click on a node and process an ajax postback to retrieve thechild nodes. In this handler you can display any progress indicator message.

The InitializeTree event handler will act like the callback, this is assumed because the UltraWebTree does not have any AfterDemandLoad event. In this handler you can hide the progress indicator message. 

var _currentNodeId = '';

var _currentNodeText = '';

function func_initializeTree(treeId)

{

    var tree;

    tree = igtree_getTreeById(treeId);

    if(_currentNodeId.length > 0 && _currentNodeText.length > 0)

    {

        var node = igtree_getNodeById(_currentNodeId);

        node.setText(_currentNodeText);

    }

    _currentNodeId = '';

    _currentNodeText = '';

} 

function func_demandLoad(treeId, nodeId)

{

    var tree = igtree_getTreeById(treeId);

    var node = igtree_getNodeById(nodeId);

    _currentNodeId = nodeId;

    _currentNodeText = node.getText();

    node.setText(_currentNodeText + ' [Loading...]');

}
 

Again a reference to the product LifeCycle page:
https://www.infragistics.com/support/product-lifecycle