e765. listening for changes to the selected item in a jcombobox component.txt

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Item events are generated whenever the selected item changes. These events are generated even while the user is moving through items in the displayed popup menu. If the combobox is editable, this event does not indicate whether the new item is taken from the predefined list or not. If this information is necessary, see e766 Listening for Action Events from a JComboBox Component. 
    // Create an editable combobox
    String[] items = {"item1", "item2"};
    JComboBox cb = new JComboBox(items);
    cb.setEditable(true);
    
    // Create and register listener
    MyItemListener actionListener = new MyItemListener();
    cb.addItemListener(actionListener);
    
    class MyItemListener implements ItemListener {
        // This method is called only if a new item has been selected.
        public void itemStateChanged(ItemEvent evt) {
            JComboBox cb = (JComboBox)evt.getSource();
    
            // Get the affected item
            Object item = evt.getItem();
    
            if (evt.getStateChange() == ItemEvent.SELECTED) {
                // Item was just selected
            } else if (evt.getStateChange() == ItemEvent.DESELECTED) {
                // Item is no longer selected
            }
        }
    }

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