JComboBox automatically executes actionPerformed after combo items are refreshed??

[sharath kv]

Hi
I want to know how to stop the JComboBox from automatically executing the actionPerformed after the JComboBox items have been updated at runtime??
i,e the JComboBox items are refreshed after I click on a child node in a JTree.
For every click on a node in the JTree the JComboBox items are refreshed,but the actionPerformed event is also executing automatically. I need the JComboBox to wait for the user input after each refresh and not perform the event automatically as soon as it is refreshed.