How to handle the change events in New UI (Experience space)

Question

for CMS Custom functionalities,we can write custom Anguilla/JS code on relevant JS files for Classic UI. how to write same Custom Code logic in New UI?

for example:

 * @param {Tridion.Core.Event} event The event is the event fired from the <c>Tridion.Controls.Dropdown</c> control.
 */
Tridion.Cme.Views.InsertCpDialog.prototype.onTemplateChange = function InsertCpDialog$onTemplateChange()
{
    // existing code
    // new code write here
}

Answer 1

Extending the new UI (known as Experience Space) is not yet supported. This functionality is expected to arrive in the next release, Tridion 10.