This can happen only on server-side. Generally, RadTreeList provides the following methods to open a new item in insert mode:
If you want this record to be automatically inserted without prompting the user to press the Insert button, you need to update the database directly and Rebind() the treelist afterwards. This can happen using the fireCommand method with a custom command, which you can then handle using the ItemCommand server-side event handler:
I hope this will prove helpful.
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