.. _TreeView.onExpand:

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TreeView.onExpand
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   void **onExpand** (:ref:`ListItem` **item**)


Parameters
----------

+----------+----------------------------------+
| **item** | The?ListItem?node that expanded. |
+----------+----------------------------------+



Description
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An event-handler callback function, called when the user expands (opens) a collapsed node in the treeview.