java - Get if someone is using a JComboBox? -

like title says, need know if using combobox. i.e. when box dropped down.

is there method this? maybe actionlistener?

use jcombobox#addpopupmenulistener():

combobox.addpopupmenulistener(new popupmenulistener() {     @override     public void popupmenuwillbecomevisible(popupmenuevent e)     {         // ...       }      @override     public void popupmenuwillbecomeinvisible(popupmenuevent e)     {         // ...       }      @override     public void popupmenucanceled(popupmenuevent e)     {         // ...     } });