Java™ How to Program, Seventh Edition

11.10. JComboBox and Using an Anonymous Inner Class for Event Handling

A combo box (sometimes called a drop-down list) provides a list of items (Fig. 11.22) from which the user can make a single selection. Combo boxes are implemented with class JComboBox, which extends class JComponent. JComboBoxes generate ItemEvents like JCheckBoxes and JRadioButtons. This example also demonstrates a special form of inner class that is used frequently in event handling.

The application of Figs. 11.21–11.22 uses a JComboBox to provide a list of four image file names from which the user can select one image to display. When the user selects a name, the application displays the corresponding image as an Icon on a JLabel. Class ComboBoxTest (Fig. 11.22) contains ...